From 73b50d211b254bf72ce10b5ea4c3e0033e3189f4 Mon Sep 17 00:00:00 2001 From: Aaron Hill Date: Sun, 29 Sep 2019 19:22:18 -0400 Subject: Add support for 'extern const fn' This works just as you might expect - an 'extern const fn' is a 'const fn' that is callable from foreign code. Currently, panicking is not allowed in consts. When RFC 2345 is stabilized, then panicking in an 'extern const fn' will produce a compile-time error when invoked at compile time, and an abort when invoked at runtime. Since this is extending the language (we're allowing the `const` keyword in a new context), I believe that this will need an FCP. However, it's a very minor change, so I didn't think that filing an RFC was necessary. This will allow libc (and other FFI crates) to make many functions `const`, without having to give up on making them `extern` as well. --- src/libsyntax/parse/mod.rs | 2 ++ 1 file changed, 2 insertions(+) (limited to 'src/libsyntax/parse/mod.rs') diff --git a/src/libsyntax/parse/mod.rs b/src/libsyntax/parse/mod.rs index fa4c1043122..1518da23b09 100644 --- a/src/libsyntax/parse/mod.rs +++ b/src/libsyntax/parse/mod.rs @@ -57,6 +57,8 @@ pub struct GatedSpans { pub yields: Lock>, /// Spans collected for gating `or_patterns`, e.g. `Some(Foo | Bar)`. pub or_patterns: Lock>, + /// Spans collected for gating `const_extern_fn`, e.g. `const extern fn foo`. + pub const_extern_fn: Lock>, } /// Info about a parsing session. -- cgit 1.4.1-3-g733a5 From 42f32f06d63b9947db63f0c739483e0294f588b2 Mon Sep 17 00:00:00 2001 From: Mazdak Farrokhzad Date: Wed, 9 Oct 2019 02:34:22 +0200 Subject: token: extract Nonterminal::to_tokenstream to parser. --- src/librustc/hir/lowering.rs | 6 +- src/libsyntax/ext/proc_macro_server.rs | 2 +- src/libsyntax/parse/mod.rs | 138 ++++++++++++++++++++++++++++++++- src/libsyntax/parse/token.rs | 137 +------------------------------- 4 files changed, 143 insertions(+), 140 deletions(-) (limited to 'src/libsyntax/parse/mod.rs') diff --git a/src/librustc/hir/lowering.rs b/src/librustc/hir/lowering.rs index 72fd054ee8a..513512b9f6b 100644 --- a/src/librustc/hir/lowering.rs +++ b/src/librustc/hir/lowering.rs @@ -70,6 +70,7 @@ use syntax::print::pprust; use syntax::source_map::{respan, ExpnData, ExpnKind, DesugaringKind, Spanned}; use syntax::symbol::{kw, sym, Symbol}; use syntax::tokenstream::{TokenStream, TokenTree}; +use syntax::parse; use syntax::parse::token::{self, Token}; use syntax::visit::{self, Visitor}; use syntax_pos::Span; @@ -1022,7 +1023,10 @@ impl<'a> LoweringContext<'a> { fn lower_token(&mut self, token: Token) -> TokenStream { match token.kind { token::Interpolated(nt) => { - let tts = nt.to_tokenstream(&self.sess.parse_sess, token.span); + // FIXME(Centril): Consider indirection `(parse_sess.nt_to_tokenstream)(...)` + // to hack around the current hack that requires `nt_to_tokenstream` to live + // in the parser. + let tts = parse::nt_to_tokenstream(&nt, &self.sess.parse_sess, token.span); self.lower_token_stream(tts) } _ => TokenTree::Token(token).into(), diff --git a/src/libsyntax/ext/proc_macro_server.rs b/src/libsyntax/ext/proc_macro_server.rs index 021ec46d987..0647c2fa313 100644 --- a/src/libsyntax/ext/proc_macro_server.rs +++ b/src/libsyntax/ext/proc_macro_server.rs @@ -174,7 +174,7 @@ impl FromInternal<(TreeAndJoint, &'_ ParseSess, &'_ mut Vec)> } Interpolated(nt) => { - let stream = nt.to_tokenstream(sess, span); + let stream = parse::nt_to_tokenstream(&nt, sess, span); TokenTree::Group(Group { delimiter: Delimiter::None, stream, diff --git a/src/libsyntax/parse/mod.rs b/src/libsyntax/parse/mod.rs index 1518da23b09..0df695d37b9 100644 --- a/src/libsyntax/parse/mod.rs +++ b/src/libsyntax/parse/mod.rs @@ -4,10 +4,9 @@ use crate::ast::{self, CrateConfig, NodeId}; use crate::early_buffered_lints::{BufferedEarlyLint, BufferedEarlyLintId}; use crate::source_map::{SourceMap, FilePathMapping}; use crate::feature_gate::UnstableFeatures; -use crate::parse::parser::Parser; -use crate::parse::parser::emit_unclosed_delims; -use crate::parse::token::TokenKind; -use crate::tokenstream::{TokenStream, TokenTree}; +use crate::parse::parser::{Parser, emit_unclosed_delims}; +use crate::parse::token::{Nonterminal, TokenKind}; +use crate::tokenstream::{self, TokenStream, TokenTree}; use crate::print::pprust; use crate::symbol::Symbol; @@ -24,6 +23,8 @@ use std::borrow::Cow; use std::path::{Path, PathBuf}; use std::str; +use log::info; + #[cfg(test)] mod tests; @@ -407,3 +408,132 @@ impl SeqSep { } } } + +// NOTE(Centril): The following probably shouldn't be here but it acknowledges the +// fact that architecturally, we are using parsing (read on below to understand why). + +pub fn nt_to_tokenstream(nt: &Nonterminal, sess: &ParseSess, span: Span) -> TokenStream { + // A `Nonterminal` is often a parsed AST item. At this point we now + // need to convert the parsed AST to an actual token stream, e.g. + // un-parse it basically. + // + // Unfortunately there's not really a great way to do that in a + // guaranteed lossless fashion right now. The fallback here is to just + // stringify the AST node and reparse it, but this loses all span + // information. + // + // As a result, some AST nodes are annotated with the token stream they + // came from. Here we attempt to extract these lossless token streams + // before we fall back to the stringification. + let tokens = match *nt { + Nonterminal::NtItem(ref item) => { + prepend_attrs(sess, &item.attrs, item.tokens.as_ref(), span) + } + Nonterminal::NtTraitItem(ref item) => { + prepend_attrs(sess, &item.attrs, item.tokens.as_ref(), span) + } + Nonterminal::NtImplItem(ref item) => { + prepend_attrs(sess, &item.attrs, item.tokens.as_ref(), span) + } + Nonterminal::NtIdent(ident, is_raw) => { + Some(tokenstream::TokenTree::token(token::Ident(ident.name, is_raw), ident.span).into()) + } + Nonterminal::NtLifetime(ident) => { + Some(tokenstream::TokenTree::token(token::Lifetime(ident.name), ident.span).into()) + } + Nonterminal::NtTT(ref tt) => { + Some(tt.clone().into()) + } + _ => None, + }; + + // FIXME(#43081): Avoid this pretty-print + reparse hack + let source = pprust::nonterminal_to_string(nt); + let filename = FileName::macro_expansion_source_code(&source); + let tokens_for_real = parse_stream_from_source_str(filename, source, sess, Some(span)); + + // During early phases of the compiler the AST could get modified + // directly (e.g., attributes added or removed) and the internal cache + // of tokens my not be invalidated or updated. Consequently if the + // "lossless" token stream disagrees with our actual stringification + // (which has historically been much more battle-tested) then we go + // with the lossy stream anyway (losing span information). + // + // Note that the comparison isn't `==` here to avoid comparing spans, + // but it *also* is a "probable" equality which is a pretty weird + // definition. We mostly want to catch actual changes to the AST + // like a `#[cfg]` being processed or some weird `macro_rules!` + // expansion. + // + // What we *don't* want to catch is the fact that a user-defined + // literal like `0xf` is stringified as `15`, causing the cached token + // stream to not be literal `==` token-wise (ignoring spans) to the + // token stream we got from stringification. + // + // Instead the "probably equal" check here is "does each token + // recursively have the same discriminant?" We basically don't look at + // the token values here and assume that such fine grained token stream + // modifications, including adding/removing typically non-semantic + // tokens such as extra braces and commas, don't happen. + if let Some(tokens) = tokens { + if tokens.probably_equal_for_proc_macro(&tokens_for_real) { + return tokens + } + info!("cached tokens found, but they're not \"probably equal\", \ + going with stringified version"); + } + return tokens_for_real +} + +fn prepend_attrs( + sess: &ParseSess, + attrs: &[ast::Attribute], + tokens: Option<&tokenstream::TokenStream>, + span: syntax_pos::Span +) -> Option { + let tokens = tokens?; + if attrs.len() == 0 { + return Some(tokens.clone()) + } + let mut builder = tokenstream::TokenStreamBuilder::new(); + for attr in attrs { + assert_eq!(attr.style, ast::AttrStyle::Outer, + "inner attributes should prevent cached tokens from existing"); + + let source = pprust::attribute_to_string(attr); + let macro_filename = FileName::macro_expansion_source_code(&source); + if attr.is_sugared_doc { + let stream = parse_stream_from_source_str(macro_filename, source, sess, Some(span)); + builder.push(stream); + continue + } + + // synthesize # [ $path $tokens ] manually here + let mut brackets = tokenstream::TokenStreamBuilder::new(); + + // For simple paths, push the identifier directly + if attr.path.segments.len() == 1 && attr.path.segments[0].args.is_none() { + let ident = attr.path.segments[0].ident; + let token = token::Ident(ident.name, ident.as_str().starts_with("r#")); + brackets.push(tokenstream::TokenTree::token(token, ident.span)); + + // ... and for more complicated paths, fall back to a reparse hack that + // should eventually be removed. + } else { + let stream = parse_stream_from_source_str(macro_filename, source, sess, Some(span)); + brackets.push(stream); + } + + brackets.push(attr.tokens.clone()); + + // The span we list here for `#` and for `[ ... ]` are both wrong in + // that it encompasses more than each token, but it hopefully is "good + // enough" for now at least. + builder.push(tokenstream::TokenTree::token(token::Pound, attr.span)); + let delim_span = tokenstream::DelimSpan::from_single(attr.span); + builder.push(tokenstream::TokenTree::Delimited( + delim_span, token::DelimToken::Bracket, brackets.build().into())); + } + builder.push(tokens.clone()); + Some(builder.build()) +} diff --git a/src/libsyntax/parse/token.rs b/src/libsyntax/parse/token.rs index fd78a2bd534..eb74ab2b919 100644 --- a/src/libsyntax/parse/token.rs +++ b/src/libsyntax/parse/token.rs @@ -4,16 +4,13 @@ pub use DelimToken::*; pub use LitKind::*; pub use TokenKind::*; -use crate::ast::{self}; -use crate::parse::{parse_stream_from_source_str, ParseSess}; -use crate::print::pprust; +use crate::ast; use crate::ptr::P; use crate::symbol::kw; -use crate::tokenstream::{self, DelimSpan, TokenStream, TokenTree}; +use crate::tokenstream::TokenTree; use syntax_pos::symbol::Symbol; -use syntax_pos::{self, Span, FileName, DUMMY_SP}; -use log::info; +use syntax_pos::{self, Span, DUMMY_SP}; use std::fmt; use std::mem; @@ -737,131 +734,3 @@ impl fmt::Debug for Nonterminal { } } } - -impl Nonterminal { - pub fn to_tokenstream(&self, sess: &ParseSess, span: Span) -> TokenStream { - // A `Nonterminal` is often a parsed AST item. At this point we now - // need to convert the parsed AST to an actual token stream, e.g. - // un-parse it basically. - // - // Unfortunately there's not really a great way to do that in a - // guaranteed lossless fashion right now. The fallback here is to just - // stringify the AST node and reparse it, but this loses all span - // information. - // - // As a result, some AST nodes are annotated with the token stream they - // came from. Here we attempt to extract these lossless token streams - // before we fall back to the stringification. - let tokens = match *self { - Nonterminal::NtItem(ref item) => { - prepend_attrs(sess, &item.attrs, item.tokens.as_ref(), span) - } - Nonterminal::NtTraitItem(ref item) => { - prepend_attrs(sess, &item.attrs, item.tokens.as_ref(), span) - } - Nonterminal::NtImplItem(ref item) => { - prepend_attrs(sess, &item.attrs, item.tokens.as_ref(), span) - } - Nonterminal::NtIdent(ident, is_raw) => { - Some(TokenTree::token(Ident(ident.name, is_raw), ident.span).into()) - } - Nonterminal::NtLifetime(ident) => { - Some(TokenTree::token(Lifetime(ident.name), ident.span).into()) - } - Nonterminal::NtTT(ref tt) => { - Some(tt.clone().into()) - } - _ => None, - }; - - // FIXME(#43081): Avoid this pretty-print + reparse hack - let source = pprust::nonterminal_to_string(self); - let filename = FileName::macro_expansion_source_code(&source); - let tokens_for_real = parse_stream_from_source_str(filename, source, sess, Some(span)); - - // During early phases of the compiler the AST could get modified - // directly (e.g., attributes added or removed) and the internal cache - // of tokens my not be invalidated or updated. Consequently if the - // "lossless" token stream disagrees with our actual stringification - // (which has historically been much more battle-tested) then we go - // with the lossy stream anyway (losing span information). - // - // Note that the comparison isn't `==` here to avoid comparing spans, - // but it *also* is a "probable" equality which is a pretty weird - // definition. We mostly want to catch actual changes to the AST - // like a `#[cfg]` being processed or some weird `macro_rules!` - // expansion. - // - // What we *don't* want to catch is the fact that a user-defined - // literal like `0xf` is stringified as `15`, causing the cached token - // stream to not be literal `==` token-wise (ignoring spans) to the - // token stream we got from stringification. - // - // Instead the "probably equal" check here is "does each token - // recursively have the same discriminant?" We basically don't look at - // the token values here and assume that such fine grained token stream - // modifications, including adding/removing typically non-semantic - // tokens such as extra braces and commas, don't happen. - if let Some(tokens) = tokens { - if tokens.probably_equal_for_proc_macro(&tokens_for_real) { - return tokens - } - info!("cached tokens found, but they're not \"probably equal\", \ - going with stringified version"); - } - return tokens_for_real - } -} - -fn prepend_attrs(sess: &ParseSess, - attrs: &[ast::Attribute], - tokens: Option<&tokenstream::TokenStream>, - span: syntax_pos::Span) - -> Option -{ - let tokens = tokens?; - if attrs.len() == 0 { - return Some(tokens.clone()) - } - let mut builder = tokenstream::TokenStreamBuilder::new(); - for attr in attrs { - assert_eq!(attr.style, ast::AttrStyle::Outer, - "inner attributes should prevent cached tokens from existing"); - - let source = pprust::attribute_to_string(attr); - let macro_filename = FileName::macro_expansion_source_code(&source); - if attr.is_sugared_doc { - let stream = parse_stream_from_source_str(macro_filename, source, sess, Some(span)); - builder.push(stream); - continue - } - - // synthesize # [ $path $tokens ] manually here - let mut brackets = tokenstream::TokenStreamBuilder::new(); - - // For simple paths, push the identifier directly - if attr.path.segments.len() == 1 && attr.path.segments[0].args.is_none() { - let ident = attr.path.segments[0].ident; - let token = Ident(ident.name, ident.as_str().starts_with("r#")); - brackets.push(tokenstream::TokenTree::token(token, ident.span)); - - // ... and for more complicated paths, fall back to a reparse hack that - // should eventually be removed. - } else { - let stream = parse_stream_from_source_str(macro_filename, source, sess, Some(span)); - brackets.push(stream); - } - - brackets.push(attr.tokens.clone()); - - // The span we list here for `#` and for `[ ... ]` are both wrong in - // that it encompasses more than each token, but it hopefully is "good - // enough" for now at least. - builder.push(tokenstream::TokenTree::token(Pound, attr.span)); - let delim_span = DelimSpan::from_single(attr.span); - builder.push(tokenstream::TokenTree::Delimited( - delim_span, DelimToken::Bracket, brackets.build().into())); - } - builder.push(tokens.clone()); - Some(builder.build()) -} -- cgit 1.4.1-3-g733a5 From 52d0e86b9a46ab74f76c0bc7b2b9df3d32fcfbc1 Mon Sep 17 00:00:00 2001 From: Mazdak Farrokhzad Date: Wed, 9 Oct 2019 03:23:10 +0200 Subject: syntax: extract sess.rs for ParseSess --- src/libsyntax/parse/mod.rs | 125 +++--------------------------------------- src/libsyntax/parse/parser.rs | 2 +- src/libsyntax/parse/sess.rs | 124 +++++++++++++++++++++++++++++++++++++++++ 3 files changed, 132 insertions(+), 119 deletions(-) create mode 100644 src/libsyntax/parse/sess.rs (limited to 'src/libsyntax/parse/mod.rs') diff --git a/src/libsyntax/parse/mod.rs b/src/libsyntax/parse/mod.rs index 0df695d37b9..53ba9b20690 100644 --- a/src/libsyntax/parse/mod.rs +++ b/src/libsyntax/parse/mod.rs @@ -1,26 +1,19 @@ //! The main parser interface. -use crate::ast::{self, CrateConfig, NodeId}; -use crate::early_buffered_lints::{BufferedEarlyLint, BufferedEarlyLintId}; -use crate::source_map::{SourceMap, FilePathMapping}; -use crate::feature_gate::UnstableFeatures; +use crate::ast; use crate::parse::parser::{Parser, emit_unclosed_delims}; use crate::parse::token::{Nonterminal, TokenKind}; use crate::tokenstream::{self, TokenStream, TokenTree}; use crate::print::pprust; -use crate::symbol::Symbol; -use errors::{Applicability, FatalError, Level, Handler, ColorConfig, Diagnostic, DiagnosticBuilder}; -use rustc_data_structures::fx::{FxHashSet, FxHashMap}; +use errors::{FatalError, Level, Diagnostic, DiagnosticBuilder}; #[cfg(target_arch = "x86_64")] use rustc_data_structures::static_assert_size; -use rustc_data_structures::sync::{Lrc, Lock, Once}; -use syntax_pos::{Span, SourceFile, FileName, MultiSpan}; -use syntax_pos::edition::Edition; -use syntax_pos::hygiene::ExpnId; +use rustc_data_structures::sync::Lrc; +use syntax_pos::{Span, SourceFile, FileName}; use std::borrow::Cow; -use std::path::{Path, PathBuf}; +use std::path::Path; use std::str; use log::info; @@ -33,6 +26,8 @@ pub mod parser; pub mod attr; pub mod lexer; pub mod token; +mod sess; +pub use sess::ParseSess; crate mod classify; crate mod diagnostics; @@ -46,112 +41,6 @@ pub type PResult<'a, T> = Result>; #[cfg(target_arch = "x86_64")] static_assert_size!(PResult<'_, bool>, 16); -/// Collected spans during parsing for places where a certain feature was -/// used and should be feature gated accordingly in `check_crate`. -#[derive(Default)] -pub struct GatedSpans { - /// Spans collected for gating `let_chains`, e.g. `if a && let b = c {}`. - pub let_chains: Lock>, - /// Spans collected for gating `async_closure`, e.g. `async || ..`. - pub async_closure: Lock>, - /// Spans collected for gating `yield e?` expressions (`generators` gate). - pub yields: Lock>, - /// Spans collected for gating `or_patterns`, e.g. `Some(Foo | Bar)`. - pub or_patterns: Lock>, - /// Spans collected for gating `const_extern_fn`, e.g. `const extern fn foo`. - pub const_extern_fn: Lock>, -} - -/// Info about a parsing session. -pub struct ParseSess { - pub span_diagnostic: Handler, - pub unstable_features: UnstableFeatures, - pub config: CrateConfig, - pub edition: Edition, - pub missing_fragment_specifiers: Lock>, - /// Places where raw identifiers were used. This is used for feature-gating raw identifiers. - pub raw_identifier_spans: Lock>, - /// Used to determine and report recursive module inclusions. - included_mod_stack: Lock>, - source_map: Lrc, - pub buffered_lints: Lock>, - /// Contains the spans of block expressions that could have been incomplete based on the - /// operation token that followed it, but that the parser cannot identify without further - /// analysis. - pub ambiguous_block_expr_parse: Lock>, - pub injected_crate_name: Once, - pub gated_spans: GatedSpans, -} - -impl ParseSess { - pub fn new(file_path_mapping: FilePathMapping) -> Self { - let cm = Lrc::new(SourceMap::new(file_path_mapping)); - let handler = Handler::with_tty_emitter( - ColorConfig::Auto, - true, - None, - Some(cm.clone()), - ); - ParseSess::with_span_handler(handler, cm) - } - - pub fn with_span_handler(handler: Handler, source_map: Lrc) -> Self { - Self { - span_diagnostic: handler, - unstable_features: UnstableFeatures::from_environment(), - config: FxHashSet::default(), - edition: ExpnId::root().expn_data().edition, - missing_fragment_specifiers: Lock::new(FxHashSet::default()), - raw_identifier_spans: Lock::new(Vec::new()), - included_mod_stack: Lock::new(vec![]), - source_map, - buffered_lints: Lock::new(vec![]), - ambiguous_block_expr_parse: Lock::new(FxHashMap::default()), - injected_crate_name: Once::new(), - gated_spans: GatedSpans::default(), - } - } - - #[inline] - pub fn source_map(&self) -> &SourceMap { - &self.source_map - } - - pub fn buffer_lint>(&self, - lint_id: BufferedEarlyLintId, - span: S, - id: NodeId, - msg: &str, - ) { - self.buffered_lints.with_lock(|buffered_lints| { - buffered_lints.push(BufferedEarlyLint{ - span: span.into(), - id, - msg: msg.into(), - lint_id, - }); - }); - } - - /// Extend an error with a suggestion to wrap an expression with parentheses to allow the - /// parser to continue parsing the following operation as part of the same expression. - pub fn expr_parentheses_needed( - &self, - err: &mut DiagnosticBuilder<'_>, - span: Span, - alt_snippet: Option, - ) { - if let Some(snippet) = self.source_map().span_to_snippet(span).ok().or(alt_snippet) { - err.span_suggestion( - span, - "parentheses are required to parse this as an expression", - format!("({})", snippet), - Applicability::MachineApplicable, - ); - } - } -} - #[derive(Clone)] pub struct Directory<'a> { pub path: Cow<'a, Path>, diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs index 478cfefc224..2b973479833 100644 --- a/src/libsyntax/parse/parser.rs +++ b/src/libsyntax/parse/parser.rs @@ -1366,7 +1366,7 @@ impl<'a> Parser<'a> { ], Applicability::MaybeIncorrect, ).span_suggestion( - self.sess.source_map.next_point(self.prev_span), + self.sess.source_map().next_point(self.prev_span), "add a semicolon", ';'.to_string(), Applicability::MaybeIncorrect, diff --git a/src/libsyntax/parse/sess.rs b/src/libsyntax/parse/sess.rs new file mode 100644 index 00000000000..e49d3954f8e --- /dev/null +++ b/src/libsyntax/parse/sess.rs @@ -0,0 +1,124 @@ +//! Contains `ParseSess` which holds state living beyond what one `Parser` might. +//! It also serves as an input to the parser itself. + +use crate::ast::{CrateConfig, NodeId}; +use crate::early_buffered_lints::{BufferedEarlyLint, BufferedEarlyLintId}; +use crate::source_map::{SourceMap, FilePathMapping}; +use crate::feature_gate::UnstableFeatures; + +use errors::{Applicability, Handler, ColorConfig, DiagnosticBuilder}; +use rustc_data_structures::fx::{FxHashSet, FxHashMap}; +use rustc_data_structures::sync::{Lrc, Lock, Once}; +use syntax_pos::{Symbol, Span, MultiSpan}; +use syntax_pos::edition::Edition; +use syntax_pos::hygiene::ExpnId; + +use std::path::PathBuf; +use std::str; + +/// Collected spans during parsing for places where a certain feature was +/// used and should be feature gated accordingly in `check_crate`. +#[derive(Default)] +crate struct GatedSpans { + /// Spans collected for gating `let_chains`, e.g. `if a && let b = c {}`. + crate let_chains: Lock>, + /// Spans collected for gating `async_closure`, e.g. `async || ..`. + crate async_closure: Lock>, + /// Spans collected for gating `yield e?` expressions (`generators` gate). + crate yields: Lock>, + /// Spans collected for gating `or_patterns`, e.g. `Some(Foo | Bar)`. + crate or_patterns: Lock>, + /// Spans collected for gating `const_extern_fn`, e.g. `const extern fn foo`. + crate const_extern_fn: Lock>, +} + +/// Info about a parsing session. +pub struct ParseSess { + pub span_diagnostic: Handler, + crate unstable_features: UnstableFeatures, + pub config: CrateConfig, + pub edition: Edition, + pub missing_fragment_specifiers: Lock>, + /// Places where raw identifiers were used. This is used for feature-gating raw identifiers. + pub raw_identifier_spans: Lock>, + /// Used to determine and report recursive module inclusions. + pub(super) included_mod_stack: Lock>, + source_map: Lrc, + pub buffered_lints: Lock>, + /// Contains the spans of block expressions that could have been incomplete based on the + /// operation token that followed it, but that the parser cannot identify without further + /// analysis. + pub ambiguous_block_expr_parse: Lock>, + pub injected_crate_name: Once, + crate gated_spans: GatedSpans, +} + +impl ParseSess { + pub fn new(file_path_mapping: FilePathMapping) -> Self { + let cm = Lrc::new(SourceMap::new(file_path_mapping)); + let handler = Handler::with_tty_emitter( + ColorConfig::Auto, + true, + None, + Some(cm.clone()), + ); + ParseSess::with_span_handler(handler, cm) + } + + pub fn with_span_handler(handler: Handler, source_map: Lrc) -> Self { + Self { + span_diagnostic: handler, + unstable_features: UnstableFeatures::from_environment(), + config: FxHashSet::default(), + edition: ExpnId::root().expn_data().edition, + missing_fragment_specifiers: Lock::new(FxHashSet::default()), + raw_identifier_spans: Lock::new(Vec::new()), + included_mod_stack: Lock::new(vec![]), + source_map, + buffered_lints: Lock::new(vec![]), + ambiguous_block_expr_parse: Lock::new(FxHashMap::default()), + injected_crate_name: Once::new(), + gated_spans: GatedSpans::default(), + } + } + + #[inline] + pub fn source_map(&self) -> &SourceMap { + &self.source_map + } + + pub fn buffer_lint( + &self, + lint_id: BufferedEarlyLintId, + span: impl Into, + id: NodeId, + msg: &str, + ) { + self.buffered_lints.with_lock(|buffered_lints| { + buffered_lints.push(BufferedEarlyLint{ + span: span.into(), + id, + msg: msg.into(), + lint_id, + }); + }); + } + + /// Extend an error with a suggestion to wrap an expression with parentheses to allow the + /// parser to continue parsing the following operation as part of the same expression. + pub fn expr_parentheses_needed( + &self, + err: &mut DiagnosticBuilder<'_>, + span: Span, + alt_snippet: Option, + ) { + if let Some(snippet) = self.source_map().span_to_snippet(span).ok().or(alt_snippet) { + err.span_suggestion( + span, + "parentheses are required to parse this as an expression", + format!("({})", snippet), + Applicability::MachineApplicable, + ); + } + } +} -- cgit 1.4.1-3-g733a5 From ae156a56d4ae27e2fca8d51aa63d5322b500c91f Mon Sep 17 00:00:00 2001 From: Mazdak Farrokhzad Date: Mon, 14 Oct 2019 10:08:26 +0200 Subject: syntax::parse::sess -> syntax::sess --- src/librustc/hir/lowering.rs | 6 +- src/librustc/hir/print.rs | 2 +- src/librustc/session/config.rs | 3 +- src/librustc/session/mod.rs | 4 +- src/librustdoc/clean/cfg.rs | 2 +- src/librustdoc/html/highlight.rs | 4 +- src/librustdoc/passes/check_code_block_syntax.rs | 3 +- src/librustdoc/test.rs | 2 +- src/libsyntax/attr/builtin.rs | 2 +- src/libsyntax/attr/mod.rs | 3 +- src/libsyntax/config.rs | 3 +- src/libsyntax/ext/base.rs | 9 +- src/libsyntax/ext/expand.rs | 3 +- src/libsyntax/ext/mbe/macro_check.rs | 2 +- src/libsyntax/ext/mbe/macro_parser.rs | 3 +- src/libsyntax/ext/mbe/macro_rules.rs | 3 +- src/libsyntax/ext/mbe/quoted.rs | 2 +- src/libsyntax/ext/proc_macro_server.rs | 3 +- src/libsyntax/feature_gate/builtin_attrs.rs | 2 +- src/libsyntax/feature_gate/check.rs | 3 +- src/libsyntax/lib.rs | 1 + src/libsyntax/parse/lexer/mod.rs | 2 +- src/libsyntax/parse/mod.rs | 3 +- src/libsyntax/parse/parser.rs | 3 +- src/libsyntax/parse/sess.rs | 124 --------------------- src/libsyntax/print/pprust.rs | 3 +- src/libsyntax/sess.rs | 124 +++++++++++++++++++++ src/libsyntax/tests.rs | 3 +- src/libsyntax_ext/cmdline_attrs.rs | 3 +- src/libsyntax_ext/deriving/generic/mod.rs | 2 +- src/libsyntax_ext/proc_macro_harness.rs | 2 +- src/libsyntax_ext/standard_library_imports.rs | 2 +- src/libsyntax_ext/test_harness.rs | 2 +- src/test/ui-fulldeps/ast_stmt_expr_attr.rs | 3 +- src/test/ui-fulldeps/mod_dir_path_canonicalized.rs | 3 +- src/test/ui-fulldeps/pprust-expr-roundtrip.rs | 4 +- 36 files changed, 182 insertions(+), 166 deletions(-) delete mode 100644 src/libsyntax/parse/sess.rs create mode 100644 src/libsyntax/sess.rs (limited to 'src/libsyntax/parse/mod.rs') diff --git a/src/librustc/hir/lowering.rs b/src/librustc/hir/lowering.rs index 747848edc7a..ab5a3c06510 100644 --- a/src/librustc/hir/lowering.rs +++ b/src/librustc/hir/lowering.rs @@ -67,11 +67,11 @@ use syntax::errors; use syntax::ext::base::SpecialDerives; use syntax::ext::hygiene::ExpnId; use syntax::print::pprust; -use syntax::source_map::{respan, ExpnData, ExpnKind, DesugaringKind, Spanned}; -use syntax::symbol::{kw, sym, Symbol}; use syntax::tokenstream::{TokenStream, TokenTree}; use syntax::parse::token::{self, Nonterminal, Token}; -use syntax::parse::ParseSess; +use syntax::sess::ParseSess; +use syntax::source_map::{respan, ExpnData, ExpnKind, DesugaringKind, Spanned}; +use syntax::symbol::{kw, sym, Symbol}; use syntax::visit::{self, Visitor}; use syntax_pos::Span; diff --git a/src/librustc/hir/print.rs b/src/librustc/hir/print.rs index 6cffaa8a494..b852098d4ce 100644 --- a/src/librustc/hir/print.rs +++ b/src/librustc/hir/print.rs @@ -1,10 +1,10 @@ use rustc_target::spec::abi::Abi; use syntax::ast; use syntax::source_map::{SourceMap, Spanned}; -use syntax::parse::ParseSess; use syntax::print::pp::{self, Breaks}; use syntax::print::pp::Breaks::{Consistent, Inconsistent}; use syntax::print::pprust::{self, Comments, PrintState}; +use syntax::sess::ParseSess; use syntax::symbol::kw; use syntax::util::parser::{self, AssocOp, Fixity}; use syntax_pos::{self, BytePos, FileName}; diff --git a/src/librustc/session/config.rs b/src/librustc/session/config.rs index 2517141542d..675e3bbd002 100644 --- a/src/librustc/session/config.rs +++ b/src/librustc/session/config.rs @@ -16,8 +16,9 @@ use syntax; use syntax::ast::{self, IntTy, UintTy, MetaItemKind}; use syntax::source_map::{FileName, FilePathMapping}; use syntax::edition::{Edition, EDITION_NAME_LIST, DEFAULT_EDITION}; -use syntax::parse::{ParseSess, new_parser_from_source_str}; +use syntax::parse::new_parser_from_source_str; use syntax::parse::token; +use syntax::sess::ParseSess; use syntax::symbol::{sym, Symbol}; use syntax::feature_gate::UnstableFeatures; use syntax::source_map::SourceMap; diff --git a/src/librustc/session/mod.rs b/src/librustc/session/mod.rs index fa2902e4f0e..c59df146629 100644 --- a/src/librustc/session/mod.rs +++ b/src/librustc/session/mod.rs @@ -28,7 +28,7 @@ use syntax::ext::allocator::AllocatorKind; use syntax::feature_gate::{self, AttributeType}; use syntax::json::JsonEmitter; use syntax::source_map; -use syntax::parse::{self, ParseSess}; +use syntax::sess::ParseSess; use syntax::symbol::Symbol; use syntax_pos::{MultiSpan, Span}; use crate::util::profiling::{SelfProfiler, SelfProfilerRef}; @@ -1159,7 +1159,7 @@ fn build_session_( ); let target_cfg = config::build_target_config(&sopts, &span_diagnostic); - let parse_sess = parse::ParseSess::with_span_handler( + let parse_sess = ParseSess::with_span_handler( span_diagnostic, source_map, ); diff --git a/src/librustdoc/clean/cfg.rs b/src/librustdoc/clean/cfg.rs index da3b52afadf..706f52d0322 100644 --- a/src/librustdoc/clean/cfg.rs +++ b/src/librustdoc/clean/cfg.rs @@ -9,7 +9,7 @@ use std::ops; use syntax::symbol::{Symbol, sym}; use syntax::ast::{MetaItem, MetaItemKind, NestedMetaItem, LitKind}; -use syntax::parse::ParseSess; +use syntax::sess::ParseSess; use syntax::feature_gate::Features; use syntax_pos::Span; diff --git a/src/librustdoc/html/highlight.rs b/src/librustdoc/html/highlight.rs index 5d86ee9721b..30c9453a643 100644 --- a/src/librustdoc/html/highlight.rs +++ b/src/librustdoc/html/highlight.rs @@ -14,7 +14,7 @@ use std::io::prelude::*; use syntax::source_map::{SourceMap, FilePathMapping}; use syntax::parse::lexer; use syntax::parse::token::{self, Token}; -use syntax::parse; +use syntax::sess::ParseSess; use syntax::symbol::{kw, sym}; use syntax_pos::{Span, FileName}; @@ -33,7 +33,7 @@ pub fn render_with_highlighting( class, tooltip).unwrap(); } - let sess = parse::ParseSess::new(FilePathMapping::empty()); + let sess = ParseSess::new(FilePathMapping::empty()); let fm = sess.source_map().new_source_file( FileName::Custom(String::from("rustdoc-highlighting")), src.to_owned(), diff --git a/src/librustdoc/passes/check_code_block_syntax.rs b/src/librustdoc/passes/check_code_block_syntax.rs index 32044e48b6f..10e15ab8881 100644 --- a/src/librustdoc/passes/check_code_block_syntax.rs +++ b/src/librustdoc/passes/check_code_block_syntax.rs @@ -1,6 +1,7 @@ use errors::Applicability; use syntax::parse::lexer::{StringReader as Lexer}; -use syntax::parse::{ParseSess, token}; +use syntax::parse::token; +use syntax::sess::ParseSess; use syntax::source_map::FilePathMapping; use syntax_pos::{InnerSpan, FileName}; diff --git a/src/librustdoc/test.rs b/src/librustdoc/test.rs index 05e6f36c958..0be6340df96 100644 --- a/src/librustdoc/test.rs +++ b/src/librustdoc/test.rs @@ -394,7 +394,7 @@ pub fn make_test(s: &str, // Uses libsyntax to parse the doctest and find if there's a main fn and the extern // crate already is included. let (already_has_main, already_has_extern_crate, found_macro) = with_globals(edition, || { - use crate::syntax::{parse::{self, ParseSess}, source_map::FilePathMapping}; + use crate::syntax::{parse, sess::ParseSess, source_map::FilePathMapping}; use errors::emitter::EmitterWriter; use errors::Handler; diff --git a/src/libsyntax/attr/builtin.rs b/src/libsyntax/attr/builtin.rs index efc48256e7c..1fe698c2572 100644 --- a/src/libsyntax/attr/builtin.rs +++ b/src/libsyntax/attr/builtin.rs @@ -4,8 +4,8 @@ use crate::ast::{self, Attribute, MetaItem, NestedMetaItem}; use crate::early_buffered_lints::BufferedEarlyLintId; use crate::ext::base::ExtCtxt; use crate::feature_gate::{Features, GatedCfg}; -use crate::parse::ParseSess; use crate::print::pprust; +use crate::sess::ParseSess; use errors::{Applicability, Handler}; use syntax_pos::hygiene::Transparency; diff --git a/src/libsyntax/attr/mod.rs b/src/libsyntax/attr/mod.rs index c2c883fd20e..d291e502c25 100644 --- a/src/libsyntax/attr/mod.rs +++ b/src/libsyntax/attr/mod.rs @@ -16,9 +16,10 @@ use crate::mut_visit::visit_clobber; use crate::source_map::{BytePos, Spanned, DUMMY_SP}; use crate::parse::lexer::comments::{doc_comment_style, strip_doc_comment_decoration}; use crate::parse::parser::Parser; -use crate::parse::{ParseSess, PResult}; +use crate::parse::PResult; use crate::parse::token::{self, Token}; use crate::ptr::P; +use crate::sess::ParseSess; use crate::symbol::{sym, Symbol}; use crate::ThinVec; use crate::tokenstream::{TokenStream, TokenTree, DelimSpan}; diff --git a/src/libsyntax/config.rs b/src/libsyntax/config.rs index 2923cc86ba0..2099d018b7b 100644 --- a/src/libsyntax/config.rs +++ b/src/libsyntax/config.rs @@ -10,8 +10,9 @@ use crate::attr; use crate::ast; use crate::edition::Edition; use crate::mut_visit::*; -use crate::parse::{token, ParseSess}; +use crate::parse::token; use crate::ptr::P; +use crate::sess::ParseSess; use crate::symbol::sym; use crate::util::map_in_place::MapInPlace; diff --git a/src/libsyntax/ext/base.rs b/src/libsyntax/ext/base.rs index 583fb3f7701..01be5642d5c 100644 --- a/src/libsyntax/ext/base.rs +++ b/src/libsyntax/ext/base.rs @@ -5,9 +5,10 @@ use crate::edition::Edition; use crate::ext::expand::{self, AstFragment, Invocation}; use crate::ext::hygiene::ExpnId; use crate::mut_visit::{self, MutVisitor}; -use crate::parse::{self, parser, ParseSess, DirectoryOwnership}; +use crate::parse::{self, parser, DirectoryOwnership}; use crate::parse::token; use crate::ptr::P; +use crate::sess::ParseSess; use crate::symbol::{kw, sym, Ident, Symbol}; use crate::{ThinVec, MACRO_ARGUMENTS}; use crate::tokenstream::{self, TokenStream}; @@ -892,7 +893,7 @@ pub struct ExpansionData { /// when a macro expansion occurs, the resulting nodes have the `backtrace() /// -> expn_data` of their expansion context stored into their span. pub struct ExtCtxt<'a> { - pub parse_sess: &'a parse::ParseSess, + pub parse_sess: &'a ParseSess, pub ecfg: expand::ExpansionConfig<'a>, pub root_path: PathBuf, pub resolver: &'a mut dyn Resolver, @@ -901,7 +902,7 @@ pub struct ExtCtxt<'a> { } impl<'a> ExtCtxt<'a> { - pub fn new(parse_sess: &'a parse::ParseSess, + pub fn new(parse_sess: &'a ParseSess, ecfg: expand::ExpansionConfig<'a>, resolver: &'a mut dyn Resolver) -> ExtCtxt<'a> { @@ -935,7 +936,7 @@ impl<'a> ExtCtxt<'a> { parse::stream_to_parser(self.parse_sess, stream, MACRO_ARGUMENTS) } pub fn source_map(&self) -> &'a SourceMap { self.parse_sess.source_map() } - pub fn parse_sess(&self) -> &'a parse::ParseSess { self.parse_sess } + pub fn parse_sess(&self) -> &'a ParseSess { self.parse_sess } pub fn cfg(&self) -> &ast::CrateConfig { &self.parse_sess.config } pub fn call_site(&self) -> Span { self.current_expansion.id.expn_data().call_site diff --git a/src/libsyntax/ext/expand.rs b/src/libsyntax/ext/expand.rs index 9fcd918cef1..9ef59778f07 100644 --- a/src/libsyntax/ext/expand.rs +++ b/src/libsyntax/ext/expand.rs @@ -10,11 +10,12 @@ use crate::ext::mbe::macro_rules::annotate_err_with_kind; use crate::ext::placeholders::{placeholder, PlaceholderExpander}; use crate::feature_gate::{self, Features, GateIssue, is_builtin_attr, emit_feature_err}; use crate::mut_visit::*; -use crate::parse::{DirectoryOwnership, PResult, ParseSess}; +use crate::parse::{DirectoryOwnership, PResult}; use crate::parse::token; use crate::parse::parser::Parser; use crate::print::pprust; use crate::ptr::P; +use crate::sess::ParseSess; use crate::symbol::{sym, Symbol}; use crate::tokenstream::{TokenStream, TokenTree}; use crate::visit::{self, Visitor}; diff --git a/src/libsyntax/ext/mbe/macro_check.rs b/src/libsyntax/ext/mbe/macro_check.rs index 97074f5cbe4..aabaff4e1c3 100644 --- a/src/libsyntax/ext/mbe/macro_check.rs +++ b/src/libsyntax/ext/mbe/macro_check.rs @@ -109,7 +109,7 @@ use crate::early_buffered_lints::BufferedEarlyLintId; use crate::ext::mbe::{KleeneToken, TokenTree}; use crate::parse::token::TokenKind; use crate::parse::token::{DelimToken, Token}; -use crate::parse::ParseSess; +use crate::sess::ParseSess; use crate::symbol::{kw, sym}; use rustc_data_structures::fx::FxHashMap; diff --git a/src/libsyntax/ext/mbe/macro_parser.rs b/src/libsyntax/ext/mbe/macro_parser.rs index 0cb5eff1ef2..ff382c316ff 100644 --- a/src/libsyntax/ext/mbe/macro_parser.rs +++ b/src/libsyntax/ext/mbe/macro_parser.rs @@ -76,10 +76,11 @@ use TokenTreeOrTokenTreeSlice::*; use crate::ast::{Ident, Name}; use crate::ext::mbe::{self, TokenTree}; -use crate::parse::{Directory, ParseSess, PResult}; +use crate::parse::{Directory, PResult}; use crate::parse::parser::{Parser, PathStyle}; use crate::parse::token::{self, DocComment, Nonterminal, Token}; use crate::print::pprust; +use crate::sess::ParseSess; use crate::symbol::{kw, sym, Symbol}; use crate::tokenstream::{DelimSpan, TokenStream}; diff --git a/src/libsyntax/ext/mbe/macro_rules.rs b/src/libsyntax/ext/mbe/macro_rules.rs index e4fc269d147..b4223298422 100644 --- a/src/libsyntax/ext/mbe/macro_rules.rs +++ b/src/libsyntax/ext/mbe/macro_rules.rs @@ -14,8 +14,9 @@ use crate::feature_gate::Features; use crate::parse::parser::Parser; use crate::parse::token::TokenKind::*; use crate::parse::token::{self, NtTT, Token}; -use crate::parse::{Directory, ParseSess}; +use crate::parse::Directory; use crate::print::pprust; +use crate::sess::ParseSess; use crate::symbol::{kw, sym, Symbol}; use crate::tokenstream::{DelimSpan, TokenStream, TokenTree}; diff --git a/src/libsyntax/ext/mbe/quoted.rs b/src/libsyntax/ext/mbe/quoted.rs index 8cb85bdef76..3cec4bc60e7 100644 --- a/src/libsyntax/ext/mbe/quoted.rs +++ b/src/libsyntax/ext/mbe/quoted.rs @@ -2,8 +2,8 @@ use crate::ast; use crate::ext::mbe::macro_parser; use crate::ext::mbe::{TokenTree, KleeneOp, KleeneToken, SequenceRepetition, Delimited}; use crate::parse::token::{self, Token}; -use crate::parse::ParseSess; use crate::print::pprust; +use crate::sess::ParseSess; use crate::symbol::kw; use crate::tokenstream; diff --git a/src/libsyntax/ext/proc_macro_server.rs b/src/libsyntax/ext/proc_macro_server.rs index 08142ba6c58..300523c1b0a 100644 --- a/src/libsyntax/ext/proc_macro_server.rs +++ b/src/libsyntax/ext/proc_macro_server.rs @@ -1,8 +1,9 @@ use crate::ast; use crate::ext::base::ExtCtxt; -use crate::parse::{self, token, ParseSess}; +use crate::parse::{self, token}; use crate::parse::lexer::comments; use crate::print::pprust; +use crate::sess::ParseSess; use crate::tokenstream::{self, DelimSpan, IsJoint::*, TokenStream, TreeAndJoint}; use errors::Diagnostic; diff --git a/src/libsyntax/feature_gate/builtin_attrs.rs b/src/libsyntax/feature_gate/builtin_attrs.rs index ab1620b9524..043a2ffb5a4 100644 --- a/src/libsyntax/feature_gate/builtin_attrs.rs +++ b/src/libsyntax/feature_gate/builtin_attrs.rs @@ -9,8 +9,8 @@ use super::active::Features; use crate::ast; use crate::attr::AttributeTemplate; +use crate::sess::ParseSess; use crate::symbol::{Symbol, sym}; -use crate::parse::ParseSess; use syntax_pos::Span; use rustc_data_structures::fx::FxHashMap; diff --git a/src/libsyntax/feature_gate/check.rs b/src/libsyntax/feature_gate/check.rs index 2f6d98213e5..700ce26171a 100644 --- a/src/libsyntax/feature_gate/check.rs +++ b/src/libsyntax/feature_gate/check.rs @@ -11,7 +11,8 @@ use crate::attr::{self, check_builtin_attribute}; use crate::source_map::Spanned; use crate::edition::{ALL_EDITIONS, Edition}; use crate::visit::{self, FnKind, Visitor}; -use crate::parse::{token, ParseSess}; +use crate::parse::token; +use crate::sess::ParseSess; use crate::symbol::{Symbol, sym}; use crate::tokenstream::TokenTree; diff --git a/src/libsyntax/lib.rs b/src/libsyntax/lib.rs index 09a47795a82..fa75f5624f8 100644 --- a/src/libsyntax/lib.rs +++ b/src/libsyntax/lib.rs @@ -147,6 +147,7 @@ pub mod ptr; pub mod show_span; pub use syntax_pos::edition; pub use syntax_pos::symbol; +pub mod sess; pub mod tokenstream; pub mod visit; diff --git a/src/libsyntax/parse/lexer/mod.rs b/src/libsyntax/parse/lexer/mod.rs index ac3feadce3a..e6dc9a4c134 100644 --- a/src/libsyntax/parse/lexer/mod.rs +++ b/src/libsyntax/parse/lexer/mod.rs @@ -1,5 +1,5 @@ -use crate::parse::ParseSess; use crate::parse::token::{self, Token, TokenKind}; +use crate::sess::ParseSess; use crate::symbol::{sym, Symbol}; use crate::parse::unescape_error_reporting::{emit_unescape_error, push_escaped_char}; diff --git a/src/libsyntax/parse/mod.rs b/src/libsyntax/parse/mod.rs index 53ba9b20690..cb90caab77a 100644 --- a/src/libsyntax/parse/mod.rs +++ b/src/libsyntax/parse/mod.rs @@ -5,6 +5,7 @@ use crate::parse::parser::{Parser, emit_unclosed_delims}; use crate::parse::token::{Nonterminal, TokenKind}; use crate::tokenstream::{self, TokenStream, TokenTree}; use crate::print::pprust; +use crate::sess::ParseSess; use errors::{FatalError, Level, Diagnostic, DiagnosticBuilder}; #[cfg(target_arch = "x86_64")] @@ -26,8 +27,6 @@ pub mod parser; pub mod attr; pub mod lexer; pub mod token; -mod sess; -pub use sess::ParseSess; crate mod classify; crate mod diagnostics; diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs index a3ac6d0c81f..86383761484 100644 --- a/src/libsyntax/parse/parser.rs +++ b/src/libsyntax/parse/parser.rs @@ -15,12 +15,13 @@ use crate::ast::{ self, DUMMY_NODE_ID, AttrStyle, Attribute, CrateSugar, Ident, IsAsync, MacDelimiter, Mutability, StrStyle, Visibility, VisibilityKind, Unsafety, }; -use crate::parse::{ParseSess, PResult, Directory, DirectoryOwnership, SeqSep}; +use crate::parse::{PResult, Directory, DirectoryOwnership, SeqSep}; use crate::parse::lexer::UnmatchedBrace; use crate::parse::lexer::comments::{doc_comment_style, strip_doc_comment_decoration}; use crate::parse::token::{self, Token, TokenKind, DelimToken}; use crate::print::pprust; use crate::ptr::P; +use crate::sess::ParseSess; use crate::source_map::respan; use crate::symbol::{kw, sym, Symbol}; use crate::tokenstream::{self, DelimSpan, TokenTree, TokenStream, TreeAndJoint}; diff --git a/src/libsyntax/parse/sess.rs b/src/libsyntax/parse/sess.rs deleted file mode 100644 index e49d3954f8e..00000000000 --- a/src/libsyntax/parse/sess.rs +++ /dev/null @@ -1,124 +0,0 @@ -//! Contains `ParseSess` which holds state living beyond what one `Parser` might. -//! It also serves as an input to the parser itself. - -use crate::ast::{CrateConfig, NodeId}; -use crate::early_buffered_lints::{BufferedEarlyLint, BufferedEarlyLintId}; -use crate::source_map::{SourceMap, FilePathMapping}; -use crate::feature_gate::UnstableFeatures; - -use errors::{Applicability, Handler, ColorConfig, DiagnosticBuilder}; -use rustc_data_structures::fx::{FxHashSet, FxHashMap}; -use rustc_data_structures::sync::{Lrc, Lock, Once}; -use syntax_pos::{Symbol, Span, MultiSpan}; -use syntax_pos::edition::Edition; -use syntax_pos::hygiene::ExpnId; - -use std::path::PathBuf; -use std::str; - -/// Collected spans during parsing for places where a certain feature was -/// used and should be feature gated accordingly in `check_crate`. -#[derive(Default)] -crate struct GatedSpans { - /// Spans collected for gating `let_chains`, e.g. `if a && let b = c {}`. - crate let_chains: Lock>, - /// Spans collected for gating `async_closure`, e.g. `async || ..`. - crate async_closure: Lock>, - /// Spans collected for gating `yield e?` expressions (`generators` gate). - crate yields: Lock>, - /// Spans collected for gating `or_patterns`, e.g. `Some(Foo | Bar)`. - crate or_patterns: Lock>, - /// Spans collected for gating `const_extern_fn`, e.g. `const extern fn foo`. - crate const_extern_fn: Lock>, -} - -/// Info about a parsing session. -pub struct ParseSess { - pub span_diagnostic: Handler, - crate unstable_features: UnstableFeatures, - pub config: CrateConfig, - pub edition: Edition, - pub missing_fragment_specifiers: Lock>, - /// Places where raw identifiers were used. This is used for feature-gating raw identifiers. - pub raw_identifier_spans: Lock>, - /// Used to determine and report recursive module inclusions. - pub(super) included_mod_stack: Lock>, - source_map: Lrc, - pub buffered_lints: Lock>, - /// Contains the spans of block expressions that could have been incomplete based on the - /// operation token that followed it, but that the parser cannot identify without further - /// analysis. - pub ambiguous_block_expr_parse: Lock>, - pub injected_crate_name: Once, - crate gated_spans: GatedSpans, -} - -impl ParseSess { - pub fn new(file_path_mapping: FilePathMapping) -> Self { - let cm = Lrc::new(SourceMap::new(file_path_mapping)); - let handler = Handler::with_tty_emitter( - ColorConfig::Auto, - true, - None, - Some(cm.clone()), - ); - ParseSess::with_span_handler(handler, cm) - } - - pub fn with_span_handler(handler: Handler, source_map: Lrc) -> Self { - Self { - span_diagnostic: handler, - unstable_features: UnstableFeatures::from_environment(), - config: FxHashSet::default(), - edition: ExpnId::root().expn_data().edition, - missing_fragment_specifiers: Lock::new(FxHashSet::default()), - raw_identifier_spans: Lock::new(Vec::new()), - included_mod_stack: Lock::new(vec![]), - source_map, - buffered_lints: Lock::new(vec![]), - ambiguous_block_expr_parse: Lock::new(FxHashMap::default()), - injected_crate_name: Once::new(), - gated_spans: GatedSpans::default(), - } - } - - #[inline] - pub fn source_map(&self) -> &SourceMap { - &self.source_map - } - - pub fn buffer_lint( - &self, - lint_id: BufferedEarlyLintId, - span: impl Into, - id: NodeId, - msg: &str, - ) { - self.buffered_lints.with_lock(|buffered_lints| { - buffered_lints.push(BufferedEarlyLint{ - span: span.into(), - id, - msg: msg.into(), - lint_id, - }); - }); - } - - /// Extend an error with a suggestion to wrap an expression with parentheses to allow the - /// parser to continue parsing the following operation as part of the same expression. - pub fn expr_parentheses_needed( - &self, - err: &mut DiagnosticBuilder<'_>, - span: Span, - alt_snippet: Option, - ) { - if let Some(snippet) = self.source_map().span_to_snippet(span).ok().or(alt_snippet) { - err.span_suggestion( - span, - "parentheses are required to parse this as an expression", - format!("({})", snippet), - Applicability::MachineApplicable, - ); - } - } -} diff --git a/src/libsyntax/print/pprust.rs b/src/libsyntax/print/pprust.rs index 68dd90b54ab..136fc355f89 100644 --- a/src/libsyntax/print/pprust.rs +++ b/src/libsyntax/print/pprust.rs @@ -6,10 +6,11 @@ use crate::attr; use crate::source_map::{self, SourceMap, Spanned}; use crate::parse::token::{self, BinOpToken, DelimToken, Nonterminal, Token, TokenKind}; use crate::parse::lexer::comments; -use crate::parse::{self, ParseSess}; +use crate::parse; use crate::print::pp::{self, Breaks}; use crate::print::pp::Breaks::{Consistent, Inconsistent}; use crate::ptr::P; +use crate::sess::ParseSess; use crate::symbol::{kw, sym}; use crate::tokenstream::{self, TokenStream, TokenTree}; diff --git a/src/libsyntax/sess.rs b/src/libsyntax/sess.rs new file mode 100644 index 00000000000..e49d3954f8e --- /dev/null +++ b/src/libsyntax/sess.rs @@ -0,0 +1,124 @@ +//! Contains `ParseSess` which holds state living beyond what one `Parser` might. +//! It also serves as an input to the parser itself. + +use crate::ast::{CrateConfig, NodeId}; +use crate::early_buffered_lints::{BufferedEarlyLint, BufferedEarlyLintId}; +use crate::source_map::{SourceMap, FilePathMapping}; +use crate::feature_gate::UnstableFeatures; + +use errors::{Applicability, Handler, ColorConfig, DiagnosticBuilder}; +use rustc_data_structures::fx::{FxHashSet, FxHashMap}; +use rustc_data_structures::sync::{Lrc, Lock, Once}; +use syntax_pos::{Symbol, Span, MultiSpan}; +use syntax_pos::edition::Edition; +use syntax_pos::hygiene::ExpnId; + +use std::path::PathBuf; +use std::str; + +/// Collected spans during parsing for places where a certain feature was +/// used and should be feature gated accordingly in `check_crate`. +#[derive(Default)] +crate struct GatedSpans { + /// Spans collected for gating `let_chains`, e.g. `if a && let b = c {}`. + crate let_chains: Lock>, + /// Spans collected for gating `async_closure`, e.g. `async || ..`. + crate async_closure: Lock>, + /// Spans collected for gating `yield e?` expressions (`generators` gate). + crate yields: Lock>, + /// Spans collected for gating `or_patterns`, e.g. `Some(Foo | Bar)`. + crate or_patterns: Lock>, + /// Spans collected for gating `const_extern_fn`, e.g. `const extern fn foo`. + crate const_extern_fn: Lock>, +} + +/// Info about a parsing session. +pub struct ParseSess { + pub span_diagnostic: Handler, + crate unstable_features: UnstableFeatures, + pub config: CrateConfig, + pub edition: Edition, + pub missing_fragment_specifiers: Lock>, + /// Places where raw identifiers were used. This is used for feature-gating raw identifiers. + pub raw_identifier_spans: Lock>, + /// Used to determine and report recursive module inclusions. + pub(super) included_mod_stack: Lock>, + source_map: Lrc, + pub buffered_lints: Lock>, + /// Contains the spans of block expressions that could have been incomplete based on the + /// operation token that followed it, but that the parser cannot identify without further + /// analysis. + pub ambiguous_block_expr_parse: Lock>, + pub injected_crate_name: Once, + crate gated_spans: GatedSpans, +} + +impl ParseSess { + pub fn new(file_path_mapping: FilePathMapping) -> Self { + let cm = Lrc::new(SourceMap::new(file_path_mapping)); + let handler = Handler::with_tty_emitter( + ColorConfig::Auto, + true, + None, + Some(cm.clone()), + ); + ParseSess::with_span_handler(handler, cm) + } + + pub fn with_span_handler(handler: Handler, source_map: Lrc) -> Self { + Self { + span_diagnostic: handler, + unstable_features: UnstableFeatures::from_environment(), + config: FxHashSet::default(), + edition: ExpnId::root().expn_data().edition, + missing_fragment_specifiers: Lock::new(FxHashSet::default()), + raw_identifier_spans: Lock::new(Vec::new()), + included_mod_stack: Lock::new(vec![]), + source_map, + buffered_lints: Lock::new(vec![]), + ambiguous_block_expr_parse: Lock::new(FxHashMap::default()), + injected_crate_name: Once::new(), + gated_spans: GatedSpans::default(), + } + } + + #[inline] + pub fn source_map(&self) -> &SourceMap { + &self.source_map + } + + pub fn buffer_lint( + &self, + lint_id: BufferedEarlyLintId, + span: impl Into, + id: NodeId, + msg: &str, + ) { + self.buffered_lints.with_lock(|buffered_lints| { + buffered_lints.push(BufferedEarlyLint{ + span: span.into(), + id, + msg: msg.into(), + lint_id, + }); + }); + } + + /// Extend an error with a suggestion to wrap an expression with parentheses to allow the + /// parser to continue parsing the following operation as part of the same expression. + pub fn expr_parentheses_needed( + &self, + err: &mut DiagnosticBuilder<'_>, + span: Span, + alt_snippet: Option, + ) { + if let Some(snippet) = self.source_map().span_to_snippet(span).ok().or(alt_snippet) { + err.span_suggestion( + span, + "parentheses are required to parse this as an expression", + format!("({})", snippet), + Applicability::MachineApplicable, + ); + } + } +} diff --git a/src/libsyntax/tests.rs b/src/libsyntax/tests.rs index f510ac9273d..fbcf368ccb7 100644 --- a/src/libsyntax/tests.rs +++ b/src/libsyntax/tests.rs @@ -1,7 +1,8 @@ use crate::{ast, panictry}; -use crate::parse::{ParseSess, PResult, source_file_to_stream}; +use crate::parse::{PResult, source_file_to_stream}; use crate::parse::new_parser_from_source_str; use crate::parse::parser::Parser; +use crate::sess::ParseSess; use crate::source_map::{SourceMap, FilePathMapping}; use crate::tokenstream::TokenStream; use crate::with_default_globals; diff --git a/src/libsyntax_ext/cmdline_attrs.rs b/src/libsyntax_ext/cmdline_attrs.rs index 203c4a83489..2c3159739e2 100644 --- a/src/libsyntax_ext/cmdline_attrs.rs +++ b/src/libsyntax_ext/cmdline_attrs.rs @@ -3,7 +3,8 @@ use syntax::ast::{self, AttrItem, AttrStyle}; use syntax::attr::mk_attr; use syntax::panictry; -use syntax::parse::{self, token, ParseSess}; +use syntax::parse::{self, token}; +use syntax::sess::ParseSess; use syntax_pos::FileName; pub fn inject(mut krate: ast::Crate, parse_sess: &ParseSess, attrs: &[String]) -> ast::Crate { diff --git a/src/libsyntax_ext/deriving/generic/mod.rs b/src/libsyntax_ext/deriving/generic/mod.rs index abdcb6c8e3d..9c3ec06d59a 100644 --- a/src/libsyntax_ext/deriving/generic/mod.rs +++ b/src/libsyntax_ext/deriving/generic/mod.rs @@ -190,8 +190,8 @@ use syntax::ext::base::{Annotatable, ExtCtxt, SpecialDerives}; use syntax::source_map::respan; use syntax::util::map_in_place::MapInPlace; use syntax::ptr::P; +use syntax::sess::ParseSess; use syntax::symbol::{Symbol, kw, sym}; -use syntax::parse::ParseSess; use syntax_pos::{Span}; use ty::{LifetimeBounds, Path, Ptr, PtrTy, Self_, Ty}; diff --git a/src/libsyntax_ext/proc_macro_harness.rs b/src/libsyntax_ext/proc_macro_harness.rs index 1d48e8231b4..1b7068818b0 100644 --- a/src/libsyntax_ext/proc_macro_harness.rs +++ b/src/libsyntax_ext/proc_macro_harness.rs @@ -6,9 +6,9 @@ use syntax::attr; use syntax::ext::base::ExtCtxt; use syntax::ext::expand::{AstFragment, ExpansionConfig}; use syntax::ext::proc_macro::is_proc_macro_attr; -use syntax::parse::ParseSess; use syntax::print::pprust; use syntax::ptr::P; +use syntax::sess::ParseSess; use syntax::symbol::{kw, sym}; use syntax::visit::{self, Visitor}; use syntax_pos::{Span, DUMMY_SP}; diff --git a/src/libsyntax_ext/standard_library_imports.rs b/src/libsyntax_ext/standard_library_imports.rs index c577b1e33cf..4f17acf2d0f 100644 --- a/src/libsyntax_ext/standard_library_imports.rs +++ b/src/libsyntax_ext/standard_library_imports.rs @@ -3,8 +3,8 @@ use syntax::edition::Edition; use syntax::ext::expand::ExpansionConfig; use syntax::ext::hygiene::AstPass; use syntax::ext::base::{ExtCtxt, Resolver}; -use syntax::parse::ParseSess; use syntax::ptr::P; +use syntax::sess::ParseSess; use syntax::symbol::{Ident, Symbol, kw, sym}; use syntax_pos::DUMMY_SP; diff --git a/src/libsyntax_ext/test_harness.rs b/src/libsyntax_ext/test_harness.rs index f79ad1419e0..0bb279c0cb0 100644 --- a/src/libsyntax_ext/test_harness.rs +++ b/src/libsyntax_ext/test_harness.rs @@ -10,8 +10,8 @@ use syntax::ext::base::{ExtCtxt, Resolver}; use syntax::ext::expand::{AstFragment, ExpansionConfig}; use syntax::feature_gate::Features; use syntax::mut_visit::{*, ExpectOne}; -use syntax::parse::ParseSess; use syntax::ptr::P; +use syntax::sess::ParseSess; use syntax::source_map::respan; use syntax::symbol::{sym, Symbol}; use syntax_pos::{Span, DUMMY_SP}; diff --git a/src/test/ui-fulldeps/ast_stmt_expr_attr.rs b/src/test/ui-fulldeps/ast_stmt_expr_attr.rs index 6c5f539b871..5479119d812 100644 --- a/src/test/ui-fulldeps/ast_stmt_expr_attr.rs +++ b/src/test/ui-fulldeps/ast_stmt_expr_attr.rs @@ -10,9 +10,10 @@ extern crate syntax; use syntax::ast::*; use syntax::attr::*; use syntax::ast; +use syntax::sess::ParseSess; use syntax::source_map::{FilePathMapping, FileName}; use syntax::parse; -use syntax::parse::{ParseSess, PResult}; +use syntax::parse::PResult; use syntax::parse::new_parser_from_source_str; use syntax::parse::parser::Parser; use syntax::parse::token; diff --git a/src/test/ui-fulldeps/mod_dir_path_canonicalized.rs b/src/test/ui-fulldeps/mod_dir_path_canonicalized.rs index 8631bcca6d2..ac97ec70be2 100644 --- a/src/test/ui-fulldeps/mod_dir_path_canonicalized.rs +++ b/src/test/ui-fulldeps/mod_dir_path_canonicalized.rs @@ -7,8 +7,9 @@ extern crate syntax; use std::path::Path; +use syntax::sess::ParseSess; use syntax::source_map::FilePathMapping; -use syntax::parse::{self, ParseSess}; +use syntax::parse; #[path = "mod_dir_simple/test.rs"] mod gravy; diff --git a/src/test/ui-fulldeps/pprust-expr-roundtrip.rs b/src/test/ui-fulldeps/pprust-expr-roundtrip.rs index d4aff735907..932a173bc67 100644 --- a/src/test/ui-fulldeps/pprust-expr-roundtrip.rs +++ b/src/test/ui-fulldeps/pprust-expr-roundtrip.rs @@ -24,14 +24,14 @@ extern crate syntax; use rustc_data_structures::thin_vec::ThinVec; use syntax::ast::*; +use syntax::sess::ParseSess; use syntax::source_map::{Spanned, DUMMY_SP, FileName}; use syntax::source_map::FilePathMapping; use syntax::mut_visit::{self, MutVisitor, visit_clobber}; -use syntax::parse::{self, ParseSess}; +use syntax::parse; use syntax::print::pprust; use syntax::ptr::P; - fn parse_expr(ps: &ParseSess, src: &str) -> Option> { let src_as_string = src.to_string(); -- cgit 1.4.1-3-g733a5 From 9dba03f6cd8b51db9423f1d2fc9c94acd72b6183 Mon Sep 17 00:00:00 2001 From: Mazdak Farrokhzad Date: Tue, 8 Oct 2019 07:39:29 +0200 Subject: move parse::attr -> parse::parser::attr --- src/libsyntax/parse/attr.rs | 330 ------------------------------------- src/libsyntax/parse/mod.rs | 1 - src/libsyntax/parse/parser.rs | 1 + src/libsyntax/parse/parser/attr.rs | 330 +++++++++++++++++++++++++++++++++++++ 4 files changed, 331 insertions(+), 331 deletions(-) delete mode 100644 src/libsyntax/parse/attr.rs create mode 100644 src/libsyntax/parse/parser/attr.rs (limited to 'src/libsyntax/parse/mod.rs') diff --git a/src/libsyntax/parse/attr.rs b/src/libsyntax/parse/attr.rs deleted file mode 100644 index 0963efcfc8a..00000000000 --- a/src/libsyntax/parse/attr.rs +++ /dev/null @@ -1,330 +0,0 @@ -use crate::attr; -use crate::ast; -use crate::parse::{SeqSep, PResult}; -use crate::parse::token::{self, Nonterminal, DelimToken}; -use crate::parse::parser::{Parser, TokenType, PathStyle}; -use crate::tokenstream::{TokenStream, TokenTree}; -use crate::source_map::Span; - -use log::debug; -use smallvec::smallvec; - -#[derive(Debug)] -enum InnerAttributeParsePolicy<'a> { - Permitted, - NotPermitted { reason: &'a str, saw_doc_comment: bool, prev_attr_sp: Option }, -} - -const DEFAULT_UNEXPECTED_INNER_ATTR_ERR_MSG: &str = "an inner attribute is not \ - permitted in this context"; - -impl<'a> Parser<'a> { - /// Parses attributes that appear before an item. - crate fn parse_outer_attributes(&mut self) -> PResult<'a, Vec> { - let mut attrs: Vec = Vec::new(); - let mut just_parsed_doc_comment = false; - loop { - debug!("parse_outer_attributes: self.token={:?}", self.token); - match self.token.kind { - token::Pound => { - let inner_error_reason = if just_parsed_doc_comment { - "an inner attribute is not permitted following an outer doc comment" - } else if !attrs.is_empty() { - "an inner attribute is not permitted following an outer attribute" - } else { - DEFAULT_UNEXPECTED_INNER_ATTR_ERR_MSG - }; - let inner_parse_policy = - InnerAttributeParsePolicy::NotPermitted { - reason: inner_error_reason, - saw_doc_comment: just_parsed_doc_comment, - prev_attr_sp: attrs.last().and_then(|a| Some(a.span)) - }; - let attr = self.parse_attribute_with_inner_parse_policy(inner_parse_policy)?; - attrs.push(attr); - just_parsed_doc_comment = false; - } - token::DocComment(s) => { - let attr = attr::mk_sugared_doc_attr(s, self.token.span); - if attr.style != ast::AttrStyle::Outer { - let mut err = self.fatal("expected outer doc comment"); - err.note("inner doc comments like this (starting with \ - `//!` or `/*!`) can only appear before items"); - return Err(err); - } - attrs.push(attr); - self.bump(); - just_parsed_doc_comment = true; - } - _ => break, - } - } - Ok(attrs) - } - - /// Matches `attribute = # ! [ meta_item ]`. - /// - /// If `permit_inner` is `true`, then a leading `!` indicates an inner - /// attribute. - pub fn parse_attribute(&mut self, permit_inner: bool) -> PResult<'a, ast::Attribute> { - debug!("parse_attribute: permit_inner={:?} self.token={:?}", - permit_inner, - self.token); - let inner_parse_policy = if permit_inner { - InnerAttributeParsePolicy::Permitted - } else { - InnerAttributeParsePolicy::NotPermitted { - reason: DEFAULT_UNEXPECTED_INNER_ATTR_ERR_MSG, - saw_doc_comment: false, - prev_attr_sp: None - } - }; - self.parse_attribute_with_inner_parse_policy(inner_parse_policy) - } - - /// The same as `parse_attribute`, except it takes in an `InnerAttributeParsePolicy` - /// that prescribes how to handle inner attributes. - fn parse_attribute_with_inner_parse_policy(&mut self, - inner_parse_policy: InnerAttributeParsePolicy<'_>) - -> PResult<'a, ast::Attribute> { - debug!("parse_attribute_with_inner_parse_policy: inner_parse_policy={:?} self.token={:?}", - inner_parse_policy, - self.token); - let (span, item, style) = match self.token.kind { - token::Pound => { - let lo = self.token.span; - self.bump(); - - if let InnerAttributeParsePolicy::Permitted = inner_parse_policy { - self.expected_tokens.push(TokenType::Token(token::Not)); - } - - let style = if self.token == token::Not { - self.bump(); - ast::AttrStyle::Inner - } else { - ast::AttrStyle::Outer - }; - - self.expect(&token::OpenDelim(token::Bracket))?; - let item = self.parse_attr_item()?; - self.expect(&token::CloseDelim(token::Bracket))?; - let hi = self.prev_span; - - let attr_sp = lo.to(hi); - - // Emit error if inner attribute is encountered and not permitted - if style == ast::AttrStyle::Inner { - if let InnerAttributeParsePolicy::NotPermitted { reason, - saw_doc_comment, prev_attr_sp } = inner_parse_policy { - let prev_attr_note = if saw_doc_comment { - "previous doc comment" - } else { - "previous outer attribute" - }; - - let mut diagnostic = self - .diagnostic() - .struct_span_err(attr_sp, reason); - - if let Some(prev_attr_sp) = prev_attr_sp { - diagnostic - .span_label(attr_sp, "not permitted following an outer attibute") - .span_label(prev_attr_sp, prev_attr_note); - } - - diagnostic - .note("inner attributes, like `#![no_std]`, annotate the item \ - enclosing them, and are usually found at the beginning of \ - source files. Outer attributes, like `#[test]`, annotate the \ - item following them.") - .emit() - } - } - - (attr_sp, item, style) - } - _ => { - let token_str = self.this_token_to_string(); - return Err(self.fatal(&format!("expected `#`, found `{}`", token_str))); - } - }; - - Ok(ast::Attribute { - item, - id: attr::mk_attr_id(), - style, - is_sugared_doc: false, - span, - }) - } - - /// Parses an inner part of an attribute (the path and following tokens). - /// The tokens must be either a delimited token stream, or empty token stream, - /// or the "legacy" key-value form. - /// PATH `(` TOKEN_STREAM `)` - /// PATH `[` TOKEN_STREAM `]` - /// PATH `{` TOKEN_STREAM `}` - /// PATH - /// PATH `=` UNSUFFIXED_LIT - /// The delimiters or `=` are still put into the resulting token stream. - pub fn parse_attr_item(&mut self) -> PResult<'a, ast::AttrItem> { - let item = match self.token.kind { - token::Interpolated(ref nt) => match **nt { - Nonterminal::NtMeta(ref item) => Some(item.clone()), - _ => None, - }, - _ => None, - }; - Ok(if let Some(item) = item { - self.bump(); - item - } else { - let path = self.parse_path(PathStyle::Mod)?; - let tokens = if self.check(&token::OpenDelim(DelimToken::Paren)) || - self.check(&token::OpenDelim(DelimToken::Bracket)) || - self.check(&token::OpenDelim(DelimToken::Brace)) { - self.parse_token_tree().into() - } else if self.eat(&token::Eq) { - let eq = TokenTree::token(token::Eq, self.prev_span); - let mut is_interpolated_expr = false; - if let token::Interpolated(nt) = &self.token.kind { - if let token::NtExpr(..) = **nt { - is_interpolated_expr = true; - } - } - let tokens = if is_interpolated_expr { - // We need to accept arbitrary interpolated expressions to continue - // supporting things like `doc = $expr` that work on stable. - // Non-literal interpolated expressions are rejected after expansion. - self.parse_token_tree().into() - } else { - self.parse_unsuffixed_lit()?.tokens() - }; - TokenStream::from_streams(smallvec![eq.into(), tokens]) - } else { - TokenStream::default() - }; - ast::AttrItem { path, tokens } - }) - } - - /// Parses attributes that appear after the opening of an item. These should - /// be preceded by an exclamation mark, but we accept and warn about one - /// terminated by a semicolon. - /// - /// Matches `inner_attrs*`. - crate fn parse_inner_attributes(&mut self) -> PResult<'a, Vec> { - let mut attrs: Vec = vec![]; - loop { - match self.token.kind { - token::Pound => { - // Don't even try to parse if it's not an inner attribute. - if !self.look_ahead(1, |t| t == &token::Not) { - break; - } - - let attr = self.parse_attribute(true)?; - assert_eq!(attr.style, ast::AttrStyle::Inner); - attrs.push(attr); - } - token::DocComment(s) => { - // We need to get the position of this token before we bump. - let attr = attr::mk_sugared_doc_attr(s, self.token.span); - if attr.style == ast::AttrStyle::Inner { - attrs.push(attr); - self.bump(); - } else { - break; - } - } - _ => break, - } - } - Ok(attrs) - } - - fn parse_unsuffixed_lit(&mut self) -> PResult<'a, ast::Lit> { - let lit = self.parse_lit()?; - debug!("checking if {:?} is unusuffixed", lit); - - if !lit.kind.is_unsuffixed() { - let msg = "suffixed literals are not allowed in attributes"; - self.diagnostic().struct_span_err(lit.span, msg) - .help("instead of using a suffixed literal \ - (1u8, 1.0f32, etc.), use an unsuffixed version \ - (1, 1.0, etc.).") - .emit() - } - - Ok(lit) - } - - /// Matches the following grammar (per RFC 1559). - /// - /// meta_item : PATH ( '=' UNSUFFIXED_LIT | '(' meta_item_inner? ')' )? ; - /// meta_item_inner : (meta_item | UNSUFFIXED_LIT) (',' meta_item_inner)? ; - pub fn parse_meta_item(&mut self) -> PResult<'a, ast::MetaItem> { - let nt_meta = match self.token.kind { - token::Interpolated(ref nt) => match **nt { - token::NtMeta(ref e) => Some(e.clone()), - _ => None, - }, - _ => None, - }; - - if let Some(item) = nt_meta { - return match item.meta(item.path.span) { - Some(meta) => { - self.bump(); - Ok(meta) - } - None => self.unexpected(), - } - } - - let lo = self.token.span; - let path = self.parse_path(PathStyle::Mod)?; - let kind = self.parse_meta_item_kind()?; - let span = lo.to(self.prev_span); - Ok(ast::MetaItem { path, kind, span }) - } - - crate fn parse_meta_item_kind(&mut self) -> PResult<'a, ast::MetaItemKind> { - Ok(if self.eat(&token::Eq) { - ast::MetaItemKind::NameValue(self.parse_unsuffixed_lit()?) - } else if self.eat(&token::OpenDelim(token::Paren)) { - ast::MetaItemKind::List(self.parse_meta_seq()?) - } else { - ast::MetaItemKind::Word - }) - } - - /// Matches `meta_item_inner : (meta_item | UNSUFFIXED_LIT) ;`. - fn parse_meta_item_inner(&mut self) -> PResult<'a, ast::NestedMetaItem> { - match self.parse_unsuffixed_lit() { - Ok(lit) => { - return Ok(ast::NestedMetaItem::Literal(lit)) - } - Err(ref mut err) => err.cancel(), - } - - match self.parse_meta_item() { - Ok(mi) => { - return Ok(ast::NestedMetaItem::MetaItem(mi)) - } - Err(ref mut err) => err.cancel(), - } - - let found = self.this_token_to_string(); - let msg = format!("expected unsuffixed literal or identifier, found `{}`", found); - Err(self.diagnostic().struct_span_err(self.token.span, &msg)) - } - - /// Matches `meta_seq = ( COMMASEP(meta_item_inner) )`. - fn parse_meta_seq(&mut self) -> PResult<'a, Vec> { - self.parse_seq_to_end(&token::CloseDelim(token::Paren), - SeqSep::trailing_allowed(token::Comma), - |p: &mut Parser<'a>| p.parse_meta_item_inner()) - } -} diff --git a/src/libsyntax/parse/mod.rs b/src/libsyntax/parse/mod.rs index cb90caab77a..6bcd9cd9b63 100644 --- a/src/libsyntax/parse/mod.rs +++ b/src/libsyntax/parse/mod.rs @@ -24,7 +24,6 @@ mod tests; #[macro_use] pub mod parser; -pub mod attr; pub mod lexer; pub mod token; diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs index 86383761484..b710fcff65b 100644 --- a/src/libsyntax/parse/parser.rs +++ b/src/libsyntax/parse/parser.rs @@ -1,3 +1,4 @@ +mod attr; mod expr; mod pat; mod item; diff --git a/src/libsyntax/parse/parser/attr.rs b/src/libsyntax/parse/parser/attr.rs new file mode 100644 index 00000000000..0963efcfc8a --- /dev/null +++ b/src/libsyntax/parse/parser/attr.rs @@ -0,0 +1,330 @@ +use crate::attr; +use crate::ast; +use crate::parse::{SeqSep, PResult}; +use crate::parse::token::{self, Nonterminal, DelimToken}; +use crate::parse::parser::{Parser, TokenType, PathStyle}; +use crate::tokenstream::{TokenStream, TokenTree}; +use crate::source_map::Span; + +use log::debug; +use smallvec::smallvec; + +#[derive(Debug)] +enum InnerAttributeParsePolicy<'a> { + Permitted, + NotPermitted { reason: &'a str, saw_doc_comment: bool, prev_attr_sp: Option }, +} + +const DEFAULT_UNEXPECTED_INNER_ATTR_ERR_MSG: &str = "an inner attribute is not \ + permitted in this context"; + +impl<'a> Parser<'a> { + /// Parses attributes that appear before an item. + crate fn parse_outer_attributes(&mut self) -> PResult<'a, Vec> { + let mut attrs: Vec = Vec::new(); + let mut just_parsed_doc_comment = false; + loop { + debug!("parse_outer_attributes: self.token={:?}", self.token); + match self.token.kind { + token::Pound => { + let inner_error_reason = if just_parsed_doc_comment { + "an inner attribute is not permitted following an outer doc comment" + } else if !attrs.is_empty() { + "an inner attribute is not permitted following an outer attribute" + } else { + DEFAULT_UNEXPECTED_INNER_ATTR_ERR_MSG + }; + let inner_parse_policy = + InnerAttributeParsePolicy::NotPermitted { + reason: inner_error_reason, + saw_doc_comment: just_parsed_doc_comment, + prev_attr_sp: attrs.last().and_then(|a| Some(a.span)) + }; + let attr = self.parse_attribute_with_inner_parse_policy(inner_parse_policy)?; + attrs.push(attr); + just_parsed_doc_comment = false; + } + token::DocComment(s) => { + let attr = attr::mk_sugared_doc_attr(s, self.token.span); + if attr.style != ast::AttrStyle::Outer { + let mut err = self.fatal("expected outer doc comment"); + err.note("inner doc comments like this (starting with \ + `//!` or `/*!`) can only appear before items"); + return Err(err); + } + attrs.push(attr); + self.bump(); + just_parsed_doc_comment = true; + } + _ => break, + } + } + Ok(attrs) + } + + /// Matches `attribute = # ! [ meta_item ]`. + /// + /// If `permit_inner` is `true`, then a leading `!` indicates an inner + /// attribute. + pub fn parse_attribute(&mut self, permit_inner: bool) -> PResult<'a, ast::Attribute> { + debug!("parse_attribute: permit_inner={:?} self.token={:?}", + permit_inner, + self.token); + let inner_parse_policy = if permit_inner { + InnerAttributeParsePolicy::Permitted + } else { + InnerAttributeParsePolicy::NotPermitted { + reason: DEFAULT_UNEXPECTED_INNER_ATTR_ERR_MSG, + saw_doc_comment: false, + prev_attr_sp: None + } + }; + self.parse_attribute_with_inner_parse_policy(inner_parse_policy) + } + + /// The same as `parse_attribute`, except it takes in an `InnerAttributeParsePolicy` + /// that prescribes how to handle inner attributes. + fn parse_attribute_with_inner_parse_policy(&mut self, + inner_parse_policy: InnerAttributeParsePolicy<'_>) + -> PResult<'a, ast::Attribute> { + debug!("parse_attribute_with_inner_parse_policy: inner_parse_policy={:?} self.token={:?}", + inner_parse_policy, + self.token); + let (span, item, style) = match self.token.kind { + token::Pound => { + let lo = self.token.span; + self.bump(); + + if let InnerAttributeParsePolicy::Permitted = inner_parse_policy { + self.expected_tokens.push(TokenType::Token(token::Not)); + } + + let style = if self.token == token::Not { + self.bump(); + ast::AttrStyle::Inner + } else { + ast::AttrStyle::Outer + }; + + self.expect(&token::OpenDelim(token::Bracket))?; + let item = self.parse_attr_item()?; + self.expect(&token::CloseDelim(token::Bracket))?; + let hi = self.prev_span; + + let attr_sp = lo.to(hi); + + // Emit error if inner attribute is encountered and not permitted + if style == ast::AttrStyle::Inner { + if let InnerAttributeParsePolicy::NotPermitted { reason, + saw_doc_comment, prev_attr_sp } = inner_parse_policy { + let prev_attr_note = if saw_doc_comment { + "previous doc comment" + } else { + "previous outer attribute" + }; + + let mut diagnostic = self + .diagnostic() + .struct_span_err(attr_sp, reason); + + if let Some(prev_attr_sp) = prev_attr_sp { + diagnostic + .span_label(attr_sp, "not permitted following an outer attibute") + .span_label(prev_attr_sp, prev_attr_note); + } + + diagnostic + .note("inner attributes, like `#![no_std]`, annotate the item \ + enclosing them, and are usually found at the beginning of \ + source files. Outer attributes, like `#[test]`, annotate the \ + item following them.") + .emit() + } + } + + (attr_sp, item, style) + } + _ => { + let token_str = self.this_token_to_string(); + return Err(self.fatal(&format!("expected `#`, found `{}`", token_str))); + } + }; + + Ok(ast::Attribute { + item, + id: attr::mk_attr_id(), + style, + is_sugared_doc: false, + span, + }) + } + + /// Parses an inner part of an attribute (the path and following tokens). + /// The tokens must be either a delimited token stream, or empty token stream, + /// or the "legacy" key-value form. + /// PATH `(` TOKEN_STREAM `)` + /// PATH `[` TOKEN_STREAM `]` + /// PATH `{` TOKEN_STREAM `}` + /// PATH + /// PATH `=` UNSUFFIXED_LIT + /// The delimiters or `=` are still put into the resulting token stream. + pub fn parse_attr_item(&mut self) -> PResult<'a, ast::AttrItem> { + let item = match self.token.kind { + token::Interpolated(ref nt) => match **nt { + Nonterminal::NtMeta(ref item) => Some(item.clone()), + _ => None, + }, + _ => None, + }; + Ok(if let Some(item) = item { + self.bump(); + item + } else { + let path = self.parse_path(PathStyle::Mod)?; + let tokens = if self.check(&token::OpenDelim(DelimToken::Paren)) || + self.check(&token::OpenDelim(DelimToken::Bracket)) || + self.check(&token::OpenDelim(DelimToken::Brace)) { + self.parse_token_tree().into() + } else if self.eat(&token::Eq) { + let eq = TokenTree::token(token::Eq, self.prev_span); + let mut is_interpolated_expr = false; + if let token::Interpolated(nt) = &self.token.kind { + if let token::NtExpr(..) = **nt { + is_interpolated_expr = true; + } + } + let tokens = if is_interpolated_expr { + // We need to accept arbitrary interpolated expressions to continue + // supporting things like `doc = $expr` that work on stable. + // Non-literal interpolated expressions are rejected after expansion. + self.parse_token_tree().into() + } else { + self.parse_unsuffixed_lit()?.tokens() + }; + TokenStream::from_streams(smallvec![eq.into(), tokens]) + } else { + TokenStream::default() + }; + ast::AttrItem { path, tokens } + }) + } + + /// Parses attributes that appear after the opening of an item. These should + /// be preceded by an exclamation mark, but we accept and warn about one + /// terminated by a semicolon. + /// + /// Matches `inner_attrs*`. + crate fn parse_inner_attributes(&mut self) -> PResult<'a, Vec> { + let mut attrs: Vec = vec![]; + loop { + match self.token.kind { + token::Pound => { + // Don't even try to parse if it's not an inner attribute. + if !self.look_ahead(1, |t| t == &token::Not) { + break; + } + + let attr = self.parse_attribute(true)?; + assert_eq!(attr.style, ast::AttrStyle::Inner); + attrs.push(attr); + } + token::DocComment(s) => { + // We need to get the position of this token before we bump. + let attr = attr::mk_sugared_doc_attr(s, self.token.span); + if attr.style == ast::AttrStyle::Inner { + attrs.push(attr); + self.bump(); + } else { + break; + } + } + _ => break, + } + } + Ok(attrs) + } + + fn parse_unsuffixed_lit(&mut self) -> PResult<'a, ast::Lit> { + let lit = self.parse_lit()?; + debug!("checking if {:?} is unusuffixed", lit); + + if !lit.kind.is_unsuffixed() { + let msg = "suffixed literals are not allowed in attributes"; + self.diagnostic().struct_span_err(lit.span, msg) + .help("instead of using a suffixed literal \ + (1u8, 1.0f32, etc.), use an unsuffixed version \ + (1, 1.0, etc.).") + .emit() + } + + Ok(lit) + } + + /// Matches the following grammar (per RFC 1559). + /// + /// meta_item : PATH ( '=' UNSUFFIXED_LIT | '(' meta_item_inner? ')' )? ; + /// meta_item_inner : (meta_item | UNSUFFIXED_LIT) (',' meta_item_inner)? ; + pub fn parse_meta_item(&mut self) -> PResult<'a, ast::MetaItem> { + let nt_meta = match self.token.kind { + token::Interpolated(ref nt) => match **nt { + token::NtMeta(ref e) => Some(e.clone()), + _ => None, + }, + _ => None, + }; + + if let Some(item) = nt_meta { + return match item.meta(item.path.span) { + Some(meta) => { + self.bump(); + Ok(meta) + } + None => self.unexpected(), + } + } + + let lo = self.token.span; + let path = self.parse_path(PathStyle::Mod)?; + let kind = self.parse_meta_item_kind()?; + let span = lo.to(self.prev_span); + Ok(ast::MetaItem { path, kind, span }) + } + + crate fn parse_meta_item_kind(&mut self) -> PResult<'a, ast::MetaItemKind> { + Ok(if self.eat(&token::Eq) { + ast::MetaItemKind::NameValue(self.parse_unsuffixed_lit()?) + } else if self.eat(&token::OpenDelim(token::Paren)) { + ast::MetaItemKind::List(self.parse_meta_seq()?) + } else { + ast::MetaItemKind::Word + }) + } + + /// Matches `meta_item_inner : (meta_item | UNSUFFIXED_LIT) ;`. + fn parse_meta_item_inner(&mut self) -> PResult<'a, ast::NestedMetaItem> { + match self.parse_unsuffixed_lit() { + Ok(lit) => { + return Ok(ast::NestedMetaItem::Literal(lit)) + } + Err(ref mut err) => err.cancel(), + } + + match self.parse_meta_item() { + Ok(mi) => { + return Ok(ast::NestedMetaItem::MetaItem(mi)) + } + Err(ref mut err) => err.cancel(), + } + + let found = self.this_token_to_string(); + let msg = format!("expected unsuffixed literal or identifier, found `{}`", found); + Err(self.diagnostic().struct_span_err(self.token.span, &msg)) + } + + /// Matches `meta_seq = ( COMMASEP(meta_item_inner) )`. + fn parse_meta_seq(&mut self) -> PResult<'a, Vec> { + self.parse_seq_to_end(&token::CloseDelim(token::Paren), + SeqSep::trailing_allowed(token::Comma), + |p: &mut Parser<'a>| p.parse_meta_item_inner()) + } +} -- cgit 1.4.1-3-g733a5 From 98017ca53a0c3ac6a10f60b47462bd3546baaaa1 Mon Sep 17 00:00:00 2001 From: Mazdak Farrokhzad Date: Tue, 8 Oct 2019 09:46:06 +0200 Subject: move diagnostics.rs into parser/ --- src/libsyntax/parse/diagnostics.rs | 1483 ----------------------------- src/libsyntax/parse/mod.rs | 1 - src/libsyntax/parse/parser.rs | 3 +- src/libsyntax/parse/parser/diagnostics.rs | 1483 +++++++++++++++++++++++++++++ src/libsyntax/parse/parser/expr.rs | 2 +- src/libsyntax/parse/parser/item.rs | 3 +- src/libsyntax/parse/parser/module.rs | 2 +- src/libsyntax/parse/parser/stmt.rs | 2 +- 8 files changed, 1490 insertions(+), 1489 deletions(-) delete mode 100644 src/libsyntax/parse/diagnostics.rs create mode 100644 src/libsyntax/parse/parser/diagnostics.rs (limited to 'src/libsyntax/parse/mod.rs') diff --git a/src/libsyntax/parse/diagnostics.rs b/src/libsyntax/parse/diagnostics.rs deleted file mode 100644 index 943838d9dda..00000000000 --- a/src/libsyntax/parse/diagnostics.rs +++ /dev/null @@ -1,1483 +0,0 @@ -use crate::ast::{ - self, Param, BinOpKind, BindingMode, BlockCheckMode, Expr, ExprKind, Ident, Item, ItemKind, - Mutability, Pat, PatKind, PathSegment, QSelf, Ty, TyKind, -}; -use crate::parse::{SeqSep, PResult, Parser}; -use crate::parse::parser::{BlockMode, PathStyle, SemiColonMode, TokenType, TokenExpectType}; -use crate::parse::token::{self, TokenKind}; -use crate::print::pprust; -use crate::ptr::P; -use crate::symbol::{kw, sym}; -use crate::ThinVec; -use crate::util::parser::AssocOp; -use errors::{Applicability, DiagnosticBuilder, DiagnosticId, pluralise}; -use rustc_data_structures::fx::FxHashSet; -use syntax_pos::{Span, DUMMY_SP, MultiSpan, SpanSnippetError}; -use log::{debug, trace}; -use std::mem; - -const TURBOFISH: &'static str = "use `::<...>` instead of `<...>` to specify type arguments"; -/// Creates a placeholder argument. -crate fn dummy_arg(ident: Ident) -> Param { - let pat = P(Pat { - id: ast::DUMMY_NODE_ID, - kind: PatKind::Ident(BindingMode::ByValue(Mutability::Immutable), ident, None), - span: ident.span, - }); - let ty = Ty { - kind: TyKind::Err, - span: ident.span, - id: ast::DUMMY_NODE_ID - }; - Param { - attrs: ThinVec::default(), - id: ast::DUMMY_NODE_ID, - pat, - span: ident.span, - ty: P(ty), - is_placeholder: false, - } -} - -pub enum Error { - FileNotFoundForModule { - mod_name: String, - default_path: String, - secondary_path: String, - dir_path: String, - }, - DuplicatePaths { - mod_name: String, - default_path: String, - secondary_path: String, - }, - UselessDocComment, - InclusiveRangeWithNoEnd, -} - -impl Error { - fn span_err>( - self, - sp: S, - handler: &errors::Handler, - ) -> DiagnosticBuilder<'_> { - match self { - Error::FileNotFoundForModule { - ref mod_name, - ref default_path, - ref secondary_path, - ref dir_path, - } => { - let mut err = struct_span_err!( - handler, - sp, - E0583, - "file not found for module `{}`", - mod_name, - ); - err.help(&format!( - "name the file either {} or {} inside the directory \"{}\"", - default_path, - secondary_path, - dir_path, - )); - err - } - Error::DuplicatePaths { ref mod_name, ref default_path, ref secondary_path } => { - let mut err = struct_span_err!( - handler, - sp, - E0584, - "file for module `{}` found at both {} and {}", - mod_name, - default_path, - secondary_path, - ); - err.help("delete or rename one of them to remove the ambiguity"); - err - } - Error::UselessDocComment => { - let mut err = struct_span_err!( - handler, - sp, - E0585, - "found a documentation comment that doesn't document anything", - ); - err.help("doc comments must come before what they document, maybe a comment was \ - intended with `//`?"); - err - } - Error::InclusiveRangeWithNoEnd => { - let mut err = struct_span_err!( - handler, - sp, - E0586, - "inclusive range with no end", - ); - err.help("inclusive ranges must be bounded at the end (`..=b` or `a..=b`)"); - err - } - } - } -} - -pub trait RecoverQPath: Sized + 'static { - const PATH_STYLE: PathStyle = PathStyle::Expr; - fn to_ty(&self) -> Option>; - fn recovered(qself: Option, path: ast::Path) -> Self; -} - -impl RecoverQPath for Ty { - const PATH_STYLE: PathStyle = PathStyle::Type; - fn to_ty(&self) -> Option> { - Some(P(self.clone())) - } - fn recovered(qself: Option, path: ast::Path) -> Self { - Self { - span: path.span, - kind: TyKind::Path(qself, path), - id: ast::DUMMY_NODE_ID, - } - } -} - -impl RecoverQPath for Pat { - fn to_ty(&self) -> Option> { - self.to_ty() - } - fn recovered(qself: Option, path: ast::Path) -> Self { - Self { - span: path.span, - kind: PatKind::Path(qself, path), - id: ast::DUMMY_NODE_ID, - } - } -} - -impl RecoverQPath for Expr { - fn to_ty(&self) -> Option> { - self.to_ty() - } - fn recovered(qself: Option, path: ast::Path) -> Self { - Self { - span: path.span, - kind: ExprKind::Path(qself, path), - attrs: ThinVec::new(), - id: ast::DUMMY_NODE_ID, - } - } -} - -impl<'a> Parser<'a> { - pub fn fatal(&self, m: &str) -> DiagnosticBuilder<'a> { - self.span_fatal(self.token.span, m) - } - - pub fn span_fatal>(&self, sp: S, m: &str) -> DiagnosticBuilder<'a> { - self.sess.span_diagnostic.struct_span_fatal(sp, m) - } - - pub fn span_fatal_err>(&self, sp: S, err: Error) -> DiagnosticBuilder<'a> { - err.span_err(sp, self.diagnostic()) - } - - pub fn bug(&self, m: &str) -> ! { - self.sess.span_diagnostic.span_bug(self.token.span, m) - } - - pub fn span_err>(&self, sp: S, m: &str) { - self.sess.span_diagnostic.span_err(sp, m) - } - - crate fn struct_span_err>(&self, sp: S, m: &str) -> DiagnosticBuilder<'a> { - self.sess.span_diagnostic.struct_span_err(sp, m) - } - - crate fn span_bug>(&self, sp: S, m: &str) -> ! { - self.sess.span_diagnostic.span_bug(sp, m) - } - - crate fn diagnostic(&self) -> &'a errors::Handler { - &self.sess.span_diagnostic - } - - crate fn span_to_snippet(&self, span: Span) -> Result { - self.sess.source_map().span_to_snippet(span) - } - - crate fn expected_ident_found(&self) -> DiagnosticBuilder<'a> { - let mut err = self.struct_span_err( - self.token.span, - &format!("expected identifier, found {}", self.this_token_descr()), - ); - if let token::Ident(name, false) = self.token.kind { - if Ident::new(name, self.token.span).is_raw_guess() { - err.span_suggestion( - self.token.span, - "you can escape reserved keywords to use them as identifiers", - format!("r#{}", name), - Applicability::MaybeIncorrect, - ); - } - } - if let Some(token_descr) = self.token_descr() { - err.span_label(self.token.span, format!("expected identifier, found {}", token_descr)); - } else { - err.span_label(self.token.span, "expected identifier"); - if self.token == token::Comma && self.look_ahead(1, |t| t.is_ident()) { - err.span_suggestion( - self.token.span, - "remove this comma", - String::new(), - Applicability::MachineApplicable, - ); - } - } - err - } - - pub fn expected_one_of_not_found( - &mut self, - edible: &[TokenKind], - inedible: &[TokenKind], - ) -> PResult<'a, bool /* recovered */> { - fn tokens_to_string(tokens: &[TokenType]) -> String { - let mut i = tokens.iter(); - // This might be a sign we need a connect method on `Iterator`. - let b = i.next() - .map_or(String::new(), |t| t.to_string()); - i.enumerate().fold(b, |mut b, (i, a)| { - if tokens.len() > 2 && i == tokens.len() - 2 { - b.push_str(", or "); - } else if tokens.len() == 2 && i == tokens.len() - 2 { - b.push_str(" or "); - } else { - b.push_str(", "); - } - b.push_str(&a.to_string()); - b - }) - } - - let mut expected = edible.iter() - .map(|x| TokenType::Token(x.clone())) - .chain(inedible.iter().map(|x| TokenType::Token(x.clone()))) - .chain(self.expected_tokens.iter().cloned()) - .collect::>(); - expected.sort_by_cached_key(|x| x.to_string()); - expected.dedup(); - let expect = tokens_to_string(&expected[..]); - let actual = self.this_token_to_string(); - let (msg_exp, (label_sp, label_exp)) = if expected.len() > 1 { - let short_expect = if expected.len() > 6 { - format!("{} possible tokens", expected.len()) - } else { - expect.clone() - }; - (format!("expected one of {}, found `{}`", expect, actual), - (self.sess.source_map().next_point(self.prev_span), - format!("expected one of {} here", short_expect))) - } else if expected.is_empty() { - (format!("unexpected token: `{}`", actual), - (self.prev_span, "unexpected token after this".to_string())) - } else { - (format!("expected {}, found `{}`", expect, actual), - (self.sess.source_map().next_point(self.prev_span), - format!("expected {} here", expect))) - }; - self.last_unexpected_token_span = Some(self.token.span); - let mut err = self.fatal(&msg_exp); - if self.token.is_ident_named(sym::and) { - err.span_suggestion_short( - self.token.span, - "use `&&` instead of `and` for the boolean operator", - "&&".to_string(), - Applicability::MaybeIncorrect, - ); - } - if self.token.is_ident_named(sym::or) { - err.span_suggestion_short( - self.token.span, - "use `||` instead of `or` for the boolean operator", - "||".to_string(), - Applicability::MaybeIncorrect, - ); - } - let sp = if self.token == token::Eof { - // This is EOF; don't want to point at the following char, but rather the last token. - self.prev_span - } else { - label_sp - }; - match self.recover_closing_delimiter(&expected.iter().filter_map(|tt| match tt { - TokenType::Token(t) => Some(t.clone()), - _ => None, - }).collect::>(), err) { - Err(e) => err = e, - Ok(recovered) => { - return Ok(recovered); - } - } - - let is_semi_suggestable = expected.iter().any(|t| match t { - TokenType::Token(token::Semi) => true, // We expect a `;` here. - _ => false, - }) && ( // A `;` would be expected before the current keyword. - self.token.is_keyword(kw::Break) || - self.token.is_keyword(kw::Continue) || - self.token.is_keyword(kw::For) || - self.token.is_keyword(kw::If) || - self.token.is_keyword(kw::Let) || - self.token.is_keyword(kw::Loop) || - self.token.is_keyword(kw::Match) || - self.token.is_keyword(kw::Return) || - self.token.is_keyword(kw::While) - ); - let sm = self.sess.source_map(); - match (sm.lookup_line(self.token.span.lo()), sm.lookup_line(sp.lo())) { - (Ok(ref a), Ok(ref b)) if a.line != b.line && is_semi_suggestable => { - // The spans are in different lines, expected `;` and found `let` or `return`. - // High likelihood that it is only a missing `;`. - err.span_suggestion_short( - label_sp, - "a semicolon may be missing here", - ";".to_string(), - Applicability::MaybeIncorrect, - ); - err.emit(); - return Ok(true); - } - (Ok(ref a), Ok(ref b)) if a.line == b.line => { - // When the spans are in the same line, it means that the only content between - // them is whitespace, point at the found token in that case: - // - // X | () => { syntax error }; - // | ^^^^^ expected one of 8 possible tokens here - // - // instead of having: - // - // X | () => { syntax error }; - // | -^^^^^ unexpected token - // | | - // | expected one of 8 possible tokens here - err.span_label(self.token.span, label_exp); - } - _ if self.prev_span == syntax_pos::DUMMY_SP => { - // Account for macro context where the previous span might not be - // available to avoid incorrect output (#54841). - err.span_label(self.token.span, "unexpected token"); - } - _ => { - err.span_label(sp, label_exp); - err.span_label(self.token.span, "unexpected token"); - } - } - self.maybe_annotate_with_ascription(&mut err, false); - Err(err) - } - - pub fn maybe_annotate_with_ascription( - &self, - err: &mut DiagnosticBuilder<'_>, - maybe_expected_semicolon: bool, - ) { - if let Some((sp, likely_path)) = self.last_type_ascription { - let sm = self.sess.source_map(); - let next_pos = sm.lookup_char_pos(self.token.span.lo()); - let op_pos = sm.lookup_char_pos(sp.hi()); - - let allow_unstable = self.sess.unstable_features.is_nightly_build(); - - if likely_path { - err.span_suggestion( - sp, - "maybe write a path separator here", - "::".to_string(), - if allow_unstable { - Applicability::MaybeIncorrect - } else { - Applicability::MachineApplicable - }, - ); - } else if op_pos.line != next_pos.line && maybe_expected_semicolon { - err.span_suggestion( - sp, - "try using a semicolon", - ";".to_string(), - Applicability::MaybeIncorrect, - ); - } else if allow_unstable { - err.span_label(sp, "tried to parse a type due to this type ascription"); - } else { - err.span_label(sp, "tried to parse a type due to this"); - } - if allow_unstable { - // Give extra information about type ascription only if it's a nightly compiler. - err.note("`#![feature(type_ascription)]` lets you annotate an expression with a \ - type: `: `"); - err.note("for more information, see \ - https://github.com/rust-lang/rust/issues/23416"); - } - } - } - - /// Eats and discards tokens until one of `kets` is encountered. Respects token trees, - /// passes through any errors encountered. Used for error recovery. - crate fn eat_to_tokens(&mut self, kets: &[&TokenKind]) { - if let Err(ref mut err) = self.parse_seq_to_before_tokens( - kets, - SeqSep::none(), - TokenExpectType::Expect, - |p| Ok(p.parse_token_tree()), - ) { - err.cancel(); - } - } - - /// This function checks if there are trailing angle brackets and produces - /// a diagnostic to suggest removing them. - /// - /// ```ignore (diagnostic) - /// let _ = vec![1, 2, 3].into_iter().collect::>>>(); - /// ^^ help: remove extra angle brackets - /// ``` - crate fn check_trailing_angle_brackets(&mut self, segment: &PathSegment, end: TokenKind) { - // This function is intended to be invoked after parsing a path segment where there are two - // cases: - // - // 1. A specific token is expected after the path segment. - // eg. `x.foo(`, `x.foo::(` (parenthesis - method call), - // `Foo::`, or `Foo::::` (mod sep - continued path). - // 2. No specific token is expected after the path segment. - // eg. `x.foo` (field access) - // - // This function is called after parsing `.foo` and before parsing the token `end` (if - // present). This includes any angle bracket arguments, such as `.foo::` or - // `Foo::`. - - // We only care about trailing angle brackets if we previously parsed angle bracket - // arguments. This helps stop us incorrectly suggesting that extra angle brackets be - // removed in this case: - // - // `x.foo >> (3)` (where `x.foo` is a `u32` for example) - // - // This case is particularly tricky as we won't notice it just looking at the tokens - - // it will appear the same (in terms of upcoming tokens) as below (since the `::` will - // have already been parsed): - // - // `x.foo::>>(3)` - let parsed_angle_bracket_args = segment.args - .as_ref() - .map(|args| args.is_angle_bracketed()) - .unwrap_or(false); - - debug!( - "check_trailing_angle_brackets: parsed_angle_bracket_args={:?}", - parsed_angle_bracket_args, - ); - if !parsed_angle_bracket_args { - return; - } - - // Keep the span at the start so we can highlight the sequence of `>` characters to be - // removed. - let lo = self.token.span; - - // We need to look-ahead to see if we have `>` characters without moving the cursor forward - // (since we might have the field access case and the characters we're eating are - // actual operators and not trailing characters - ie `x.foo >> 3`). - let mut position = 0; - - // We can encounter `>` or `>>` tokens in any order, so we need to keep track of how - // many of each (so we can correctly pluralize our error messages) and continue to - // advance. - let mut number_of_shr = 0; - let mut number_of_gt = 0; - while self.look_ahead(position, |t| { - trace!("check_trailing_angle_brackets: t={:?}", t); - if *t == token::BinOp(token::BinOpToken::Shr) { - number_of_shr += 1; - true - } else if *t == token::Gt { - number_of_gt += 1; - true - } else { - false - } - }) { - position += 1; - } - - // If we didn't find any trailing `>` characters, then we have nothing to error about. - debug!( - "check_trailing_angle_brackets: number_of_gt={:?} number_of_shr={:?}", - number_of_gt, number_of_shr, - ); - if number_of_gt < 1 && number_of_shr < 1 { - return; - } - - // Finally, double check that we have our end token as otherwise this is the - // second case. - if self.look_ahead(position, |t| { - trace!("check_trailing_angle_brackets: t={:?}", t); - *t == end - }) { - // Eat from where we started until the end token so that parsing can continue - // as if we didn't have those extra angle brackets. - self.eat_to_tokens(&[&end]); - let span = lo.until(self.token.span); - - let total_num_of_gt = number_of_gt + number_of_shr * 2; - self.diagnostic() - .struct_span_err( - span, - &format!("unmatched angle bracket{}", pluralise!(total_num_of_gt)), - ) - .span_suggestion( - span, - &format!("remove extra angle bracket{}", pluralise!(total_num_of_gt)), - String::new(), - Applicability::MachineApplicable, - ) - .emit(); - } - } - - /// Produces an error if comparison operators are chained (RFC #558). - /// We only need to check the LHS, not the RHS, because all comparison ops have same - /// precedence (see `fn precedence`) and are left-associative (see `fn fixity`). - /// - /// This can also be hit if someone incorrectly writes `foo()` when they should have used - /// the turbofish (`foo::()`) syntax. We attempt some heuristic recovery if that is the - /// case. - /// - /// Keep in mind that given that `outer_op.is_comparison()` holds and comparison ops are left - /// associative we can infer that we have: - /// - /// outer_op - /// / \ - /// inner_op r2 - /// / \ - /// l1 r1 - crate fn check_no_chained_comparison( - &mut self, - lhs: &Expr, - outer_op: &AssocOp, - ) -> PResult<'a, Option>> { - debug_assert!( - outer_op.is_comparison(), - "check_no_chained_comparison: {:?} is not comparison", - outer_op, - ); - - let mk_err_expr = |this: &Self, span| { - Ok(Some(this.mk_expr(span, ExprKind::Err, ThinVec::new()))) - }; - - match lhs.kind { - ExprKind::Binary(op, _, _) if op.node.is_comparison() => { - // Respan to include both operators. - let op_span = op.span.to(self.prev_span); - let mut err = self.struct_span_err( - op_span, - "chained comparison operators require parentheses", - ); - - let suggest = |err: &mut DiagnosticBuilder<'_>| { - err.span_suggestion_verbose( - op_span.shrink_to_lo(), - TURBOFISH, - "::".to_string(), - Applicability::MaybeIncorrect, - ); - }; - - if op.node == BinOpKind::Lt && - *outer_op == AssocOp::Less || // Include `<` to provide this recommendation - *outer_op == AssocOp::Greater // even in a case like the following: - { // Foo>> - if *outer_op == AssocOp::Less { - let snapshot = self.clone(); - self.bump(); - // So far we have parsed `foo(` or `foo< bar >::`, so we rewind the - // parser and bail out. - mem::replace(self, snapshot.clone()); - } - } - return if token::ModSep == self.token.kind { - // We have some certainty that this was a bad turbofish at this point. - // `foo< bar >::` - suggest(&mut err); - - let snapshot = self.clone(); - self.bump(); // `::` - - // Consume the rest of the likely `foo::new()` or return at `foo`. - match self.parse_expr() { - Ok(_) => { - // 99% certain that the suggestion is correct, continue parsing. - err.emit(); - // FIXME: actually check that the two expressions in the binop are - // paths and resynthesize new fn call expression instead of using - // `ExprKind::Err` placeholder. - mk_err_expr(self, lhs.span.to(self.prev_span)) - } - Err(mut expr_err) => { - expr_err.cancel(); - // Not entirely sure now, but we bubble the error up with the - // suggestion. - mem::replace(self, snapshot); - Err(err) - } - } - } else if token::OpenDelim(token::Paren) == self.token.kind { - // We have high certainty that this was a bad turbofish at this point. - // `foo< bar >(` - suggest(&mut err); - // Consume the fn call arguments. - match self.consume_fn_args() { - Err(()) => Err(err), - Ok(()) => { - err.emit(); - // FIXME: actually check that the two expressions in the binop are - // paths and resynthesize new fn call expression instead of using - // `ExprKind::Err` placeholder. - mk_err_expr(self, lhs.span.to(self.prev_span)) - } - } - } else { - // All we know is that this is `foo < bar >` and *nothing* else. Try to - // be helpful, but don't attempt to recover. - err.help(TURBOFISH); - err.help("or use `(...)` if you meant to specify fn arguments"); - // These cases cause too many knock-down errors, bail out (#61329). - Err(err) - }; - } - err.emit(); - } - _ => {} - } - Ok(None) - } - - fn consume_fn_args(&mut self) -> Result<(), ()> { - let snapshot = self.clone(); - self.bump(); // `(` - - // Consume the fn call arguments. - let modifiers = [ - (token::OpenDelim(token::Paren), 1), - (token::CloseDelim(token::Paren), -1), - ]; - self.consume_tts(1, &modifiers[..]); - - if self.token.kind == token::Eof { - // Not entirely sure that what we consumed were fn arguments, rollback. - mem::replace(self, snapshot); - Err(()) - } else { - // 99% certain that the suggestion is correct, continue parsing. - Ok(()) - } - } - - crate fn maybe_report_ambiguous_plus( - &mut self, - allow_plus: bool, - impl_dyn_multi: bool, - ty: &Ty, - ) { - if !allow_plus && impl_dyn_multi { - let sum_with_parens = format!("({})", pprust::ty_to_string(&ty)); - self.struct_span_err(ty.span, "ambiguous `+` in a type") - .span_suggestion( - ty.span, - "use parentheses to disambiguate", - sum_with_parens, - Applicability::MachineApplicable, - ) - .emit(); - } - } - - pub(super) fn maybe_recover_from_bad_type_plus( - &mut self, - allow_plus: bool, - ty: &Ty, - ) -> PResult<'a, ()> { - // Do not add `+` to expected tokens. - if !allow_plus || !self.token.is_like_plus() { - return Ok(()); - } - - self.bump(); // `+` - let bounds = self.parse_generic_bounds(None)?; - let sum_span = ty.span.to(self.prev_span); - - let mut err = struct_span_err!( - self.sess.span_diagnostic, - sum_span, - E0178, - "expected a path on the left-hand side of `+`, not `{}`", - pprust::ty_to_string(ty) - ); - - match ty.kind { - TyKind::Rptr(ref lifetime, ref mut_ty) => { - let sum_with_parens = pprust::to_string(|s| { - s.s.word("&"); - s.print_opt_lifetime(lifetime); - s.print_mutability(mut_ty.mutbl); - s.popen(); - s.print_type(&mut_ty.ty); - s.print_type_bounds(" +", &bounds); - s.pclose() - }); - err.span_suggestion( - sum_span, - "try adding parentheses", - sum_with_parens, - Applicability::MachineApplicable, - ); - } - TyKind::Ptr(..) | TyKind::BareFn(..) => { - err.span_label(sum_span, "perhaps you forgot parentheses?"); - } - _ => { - err.span_label(sum_span, "expected a path"); - } - } - err.emit(); - Ok(()) - } - - /// Tries to recover from associated item paths like `[T]::AssocItem` / `(T, U)::AssocItem`. - /// Attempts to convert the base expression/pattern/type into a type, parses the `::AssocItem` - /// tail, and combines them into a `::AssocItem` expression/pattern/type. - crate fn maybe_recover_from_bad_qpath( - &mut self, - base: P, - allow_recovery: bool, - ) -> PResult<'a, P> { - // Do not add `::` to expected tokens. - if allow_recovery && self.token == token::ModSep { - if let Some(ty) = base.to_ty() { - return self.maybe_recover_from_bad_qpath_stage_2(ty.span, ty); - } - } - Ok(base) - } - - /// Given an already parsed `Ty`, parses the `::AssocItem` tail and - /// combines them into a `::AssocItem` expression/pattern/type. - crate fn maybe_recover_from_bad_qpath_stage_2( - &mut self, - ty_span: Span, - ty: P, - ) -> PResult<'a, P> { - self.expect(&token::ModSep)?; - - let mut path = ast::Path { - segments: Vec::new(), - span: DUMMY_SP, - }; - self.parse_path_segments(&mut path.segments, T::PATH_STYLE)?; - path.span = ty_span.to(self.prev_span); - - let ty_str = self - .span_to_snippet(ty_span) - .unwrap_or_else(|_| pprust::ty_to_string(&ty)); - self.diagnostic() - .struct_span_err(path.span, "missing angle brackets in associated item path") - .span_suggestion( - // This is a best-effort recovery. - path.span, - "try", - format!("<{}>::{}", ty_str, pprust::path_to_string(&path)), - Applicability::MaybeIncorrect, - ) - .emit(); - - let path_span = ty_span.shrink_to_hi(); // Use an empty path since `position == 0`. - Ok(P(T::recovered( - Some(QSelf { - ty, - path_span, - position: 0, - }), - path, - ))) - } - - crate fn maybe_consume_incorrect_semicolon(&mut self, items: &[P]) -> bool { - if self.eat(&token::Semi) { - let mut err = self.struct_span_err(self.prev_span, "expected item, found `;`"); - err.span_suggestion_short( - self.prev_span, - "remove this semicolon", - String::new(), - Applicability::MachineApplicable, - ); - if !items.is_empty() { - let previous_item = &items[items.len() - 1]; - let previous_item_kind_name = match previous_item.kind { - // Say "braced struct" because tuple-structs and - // braceless-empty-struct declarations do take a semicolon. - ItemKind::Struct(..) => Some("braced struct"), - ItemKind::Enum(..) => Some("enum"), - ItemKind::Trait(..) => Some("trait"), - ItemKind::Union(..) => Some("union"), - _ => None, - }; - if let Some(name) = previous_item_kind_name { - err.help(&format!( - "{} declarations are not followed by a semicolon", - name - )); - } - } - err.emit(); - true - } else { - false - } - } - - /// Creates a `DiagnosticBuilder` for an unexpected token `t` and tries to recover if it is a - /// closing delimiter. - pub fn unexpected_try_recover( - &mut self, - t: &TokenKind, - ) -> PResult<'a, bool /* recovered */> { - let token_str = pprust::token_kind_to_string(t); - let this_token_str = self.this_token_descr(); - let (prev_sp, sp) = match (&self.token.kind, self.subparser_name) { - // Point at the end of the macro call when reaching end of macro arguments. - (token::Eof, Some(_)) => { - let sp = self.sess.source_map().next_point(self.token.span); - (sp, sp) - } - // We don't want to point at the following span after DUMMY_SP. - // This happens when the parser finds an empty TokenStream. - _ if self.prev_span == DUMMY_SP => (self.token.span, self.token.span), - // EOF, don't want to point at the following char, but rather the last token. - (token::Eof, None) => (self.prev_span, self.token.span), - _ => (self.sess.source_map().next_point(self.prev_span), self.token.span), - }; - let msg = format!( - "expected `{}`, found {}", - token_str, - match (&self.token.kind, self.subparser_name) { - (token::Eof, Some(origin)) => format!("end of {}", origin), - _ => this_token_str, - }, - ); - let mut err = self.struct_span_err(sp, &msg); - let label_exp = format!("expected `{}`", token_str); - match self.recover_closing_delimiter(&[t.clone()], err) { - Err(e) => err = e, - Ok(recovered) => { - return Ok(recovered); - } - } - let sm = self.sess.source_map(); - match (sm.lookup_line(prev_sp.lo()), sm.lookup_line(sp.lo())) { - (Ok(ref a), Ok(ref b)) if a.line == b.line => { - // When the spans are in the same line, it means that the only content - // between them is whitespace, point only at the found token. - err.span_label(sp, label_exp); - } - _ => { - err.span_label(prev_sp, label_exp); - err.span_label(sp, "unexpected token"); - } - } - Err(err) - } - - crate fn parse_semi_or_incorrect_foreign_fn_body( - &mut self, - ident: &Ident, - extern_sp: Span, - ) -> PResult<'a, ()> { - if self.token != token::Semi { - // This might be an incorrect fn definition (#62109). - let parser_snapshot = self.clone(); - match self.parse_inner_attrs_and_block() { - Ok((_, body)) => { - self.struct_span_err(ident.span, "incorrect `fn` inside `extern` block") - .span_label(ident.span, "can't have a body") - .span_label(body.span, "this body is invalid here") - .span_label( - extern_sp, - "`extern` blocks define existing foreign functions and `fn`s \ - inside of them cannot have a body") - .help("you might have meant to write a function accessible through ffi, \ - which can be done by writing `extern fn` outside of the \ - `extern` block") - .note("for more information, visit \ - https://doc.rust-lang.org/std/keyword.extern.html") - .emit(); - } - Err(mut err) => { - err.cancel(); - mem::replace(self, parser_snapshot); - self.expect(&token::Semi)?; - } - } - } else { - self.bump(); - } - Ok(()) - } - - /// Consumes alternative await syntaxes like `await!()`, `await `, - /// `await? `, `await()`, and `await { }`. - crate fn parse_incorrect_await_syntax( - &mut self, - lo: Span, - await_sp: Span, - ) -> PResult<'a, (Span, ExprKind)> { - if self.token == token::Not { - // Handle `await!()`. - self.expect(&token::Not)?; - self.expect(&token::OpenDelim(token::Paren))?; - let expr = self.parse_expr()?; - self.expect(&token::CloseDelim(token::Paren))?; - let sp = self.error_on_incorrect_await(lo, self.prev_span, &expr, false); - return Ok((sp, ExprKind::Await(expr))) - } - - let is_question = self.eat(&token::Question); // Handle `await? `. - let expr = if self.token == token::OpenDelim(token::Brace) { - // Handle `await { }`. - // This needs to be handled separatedly from the next arm to avoid - // interpreting `await { }?` as `?.await`. - self.parse_block_expr( - None, - self.token.span, - BlockCheckMode::Default, - ThinVec::new(), - ) - } else { - self.parse_expr() - }.map_err(|mut err| { - err.span_label(await_sp, "while parsing this incorrect await expression"); - err - })?; - let sp = self.error_on_incorrect_await(lo, expr.span, &expr, is_question); - Ok((sp, ExprKind::Await(expr))) - } - - fn error_on_incorrect_await(&self, lo: Span, hi: Span, expr: &Expr, is_question: bool) -> Span { - let expr_str = self.span_to_snippet(expr.span) - .unwrap_or_else(|_| pprust::expr_to_string(&expr)); - let suggestion = format!("{}.await{}", expr_str, if is_question { "?" } else { "" }); - let sp = lo.to(hi); - let app = match expr.kind { - ExprKind::Try(_) => Applicability::MaybeIncorrect, // `await ?` - _ => Applicability::MachineApplicable, - }; - self.struct_span_err(sp, "incorrect use of `await`") - .span_suggestion(sp, "`await` is a postfix operation", suggestion, app) - .emit(); - sp - } - - /// If encountering `future.await()`, consumes and emits an error. - crate fn recover_from_await_method_call(&mut self) { - if self.token == token::OpenDelim(token::Paren) && - self.look_ahead(1, |t| t == &token::CloseDelim(token::Paren)) - { - // future.await() - let lo = self.token.span; - self.bump(); // ( - let sp = lo.to(self.token.span); - self.bump(); // ) - self.struct_span_err(sp, "incorrect use of `await`") - .span_suggestion( - sp, - "`await` is not a method call, remove the parentheses", - String::new(), - Applicability::MachineApplicable, - ).emit() - } - } - - /// Recovers a situation like `for ( $pat in $expr )` - /// and suggest writing `for $pat in $expr` instead. - /// - /// This should be called before parsing the `$block`. - crate fn recover_parens_around_for_head( - &mut self, - pat: P, - expr: &Expr, - begin_paren: Option, - ) -> P { - match (&self.token.kind, begin_paren) { - (token::CloseDelim(token::Paren), Some(begin_par_sp)) => { - self.bump(); - - let pat_str = self - // Remove the `(` from the span of the pattern: - .span_to_snippet(pat.span.trim_start(begin_par_sp).unwrap()) - .unwrap_or_else(|_| pprust::pat_to_string(&pat)); - - self.struct_span_err(self.prev_span, "unexpected closing `)`") - .span_label(begin_par_sp, "opening `(`") - .span_suggestion( - begin_par_sp.to(self.prev_span), - "remove parenthesis in `for` loop", - format!("{} in {}", pat_str, pprust::expr_to_string(&expr)), - // With e.g. `for (x) in y)` this would replace `(x) in y)` - // with `x) in y)` which is syntactically invalid. - // However, this is prevented before we get here. - Applicability::MachineApplicable, - ) - .emit(); - - // Unwrap `(pat)` into `pat` to avoid the `unused_parens` lint. - pat.and_then(|pat| match pat.kind { - PatKind::Paren(pat) => pat, - _ => P(pat), - }) - } - _ => pat, - } - } - - crate fn could_ascription_be_path(&self, node: &ast::ExprKind) -> bool { - self.token.is_ident() && - if let ast::ExprKind::Path(..) = node { true } else { false } && - !self.token.is_reserved_ident() && // v `foo:bar(baz)` - self.look_ahead(1, |t| t == &token::OpenDelim(token::Paren)) || - self.look_ahead(1, |t| t == &token::Lt) && // `foo:bar` - } - - crate fn recover_seq_parse_error( - &mut self, - delim: token::DelimToken, - lo: Span, - result: PResult<'a, P>, - ) -> P { - match result { - Ok(x) => x, - Err(mut err) => { - err.emit(); - // Recover from parse error. - self.consume_block(delim); - self.mk_expr(lo.to(self.prev_span), ExprKind::Err, ThinVec::new()) - } - } - } - - crate fn recover_closing_delimiter( - &mut self, - tokens: &[TokenKind], - mut err: DiagnosticBuilder<'a>, - ) -> PResult<'a, bool> { - let mut pos = None; - // We want to use the last closing delim that would apply. - for (i, unmatched) in self.unclosed_delims.iter().enumerate().rev() { - if tokens.contains(&token::CloseDelim(unmatched.expected_delim)) - && Some(self.token.span) > unmatched.unclosed_span - { - pos = Some(i); - } - } - match pos { - Some(pos) => { - // Recover and assume that the detected unclosed delimiter was meant for - // this location. Emit the diagnostic and act as if the delimiter was - // present for the parser's sake. - - // Don't attempt to recover from this unclosed delimiter more than once. - let unmatched = self.unclosed_delims.remove(pos); - let delim = TokenType::Token(token::CloseDelim(unmatched.expected_delim)); - - // We want to suggest the inclusion of the closing delimiter where it makes - // the most sense, which is immediately after the last token: - // - // {foo(bar {}} - // - ^ - // | | - // | help: `)` may belong here - // | - // unclosed delimiter - if let Some(sp) = unmatched.unclosed_span { - err.span_label(sp, "unclosed delimiter"); - } - err.span_suggestion_short( - self.sess.source_map().next_point(self.prev_span), - &format!("{} may belong here", delim.to_string()), - delim.to_string(), - Applicability::MaybeIncorrect, - ); - err.emit(); - self.expected_tokens.clear(); // reduce errors - Ok(true) - } - _ => Err(err), - } - } - - /// Recovers from `pub` keyword in places where it seems _reasonable_ but isn't valid. - crate fn eat_bad_pub(&mut self) { - if self.token.is_keyword(kw::Pub) { - match self.parse_visibility(false) { - Ok(vis) => { - self.diagnostic() - .struct_span_err(vis.span, "unnecessary visibility qualifier") - .span_label(vis.span, "`pub` not permitted here") - .emit(); - } - Err(mut err) => err.emit(), - } - } - } - - /// Eats tokens until we can be relatively sure we reached the end of the - /// statement. This is something of a best-effort heuristic. - /// - /// We terminate when we find an unmatched `}` (without consuming it). - crate fn recover_stmt(&mut self) { - self.recover_stmt_(SemiColonMode::Ignore, BlockMode::Ignore) - } - - /// If `break_on_semi` is `Break`, then we will stop consuming tokens after - /// finding (and consuming) a `;` outside of `{}` or `[]` (note that this is - /// approximate -- it can mean we break too early due to macros, but that - /// should only lead to sub-optimal recovery, not inaccurate parsing). - /// - /// If `break_on_block` is `Break`, then we will stop consuming tokens - /// after finding (and consuming) a brace-delimited block. - crate fn recover_stmt_(&mut self, break_on_semi: SemiColonMode, break_on_block: BlockMode) { - let mut brace_depth = 0; - let mut bracket_depth = 0; - let mut in_block = false; - debug!("recover_stmt_ enter loop (semi={:?}, block={:?})", - break_on_semi, break_on_block); - loop { - debug!("recover_stmt_ loop {:?}", self.token); - match self.token.kind { - token::OpenDelim(token::DelimToken::Brace) => { - brace_depth += 1; - self.bump(); - if break_on_block == BlockMode::Break && - brace_depth == 1 && - bracket_depth == 0 { - in_block = true; - } - } - token::OpenDelim(token::DelimToken::Bracket) => { - bracket_depth += 1; - self.bump(); - } - token::CloseDelim(token::DelimToken::Brace) => { - if brace_depth == 0 { - debug!("recover_stmt_ return - close delim {:?}", self.token); - break; - } - brace_depth -= 1; - self.bump(); - if in_block && bracket_depth == 0 && brace_depth == 0 { - debug!("recover_stmt_ return - block end {:?}", self.token); - break; - } - } - token::CloseDelim(token::DelimToken::Bracket) => { - bracket_depth -= 1; - if bracket_depth < 0 { - bracket_depth = 0; - } - self.bump(); - } - token::Eof => { - debug!("recover_stmt_ return - Eof"); - break; - } - token::Semi => { - self.bump(); - if break_on_semi == SemiColonMode::Break && - brace_depth == 0 && - bracket_depth == 0 { - debug!("recover_stmt_ return - Semi"); - break; - } - } - token::Comma if break_on_semi == SemiColonMode::Comma && - brace_depth == 0 && - bracket_depth == 0 => - { - debug!("recover_stmt_ return - Semi"); - break; - } - _ => { - self.bump() - } - } - } - } - - crate fn check_for_for_in_in_typo(&mut self, in_span: Span) { - if self.eat_keyword(kw::In) { - // a common typo: `for _ in in bar {}` - self.struct_span_err(self.prev_span, "expected iterable, found keyword `in`") - .span_suggestion_short( - in_span.until(self.prev_span), - "remove the duplicated `in`", - String::new(), - Applicability::MachineApplicable, - ) - .emit(); - } - } - - crate fn expected_semi_or_open_brace(&mut self) -> PResult<'a, T> { - let token_str = self.this_token_descr(); - let mut err = self.fatal(&format!("expected `;` or `{{`, found {}", token_str)); - err.span_label(self.token.span, "expected `;` or `{`"); - Err(err) - } - - crate fn eat_incorrect_doc_comment_for_param_type(&mut self) { - if let token::DocComment(_) = self.token.kind { - self.struct_span_err( - self.token.span, - "documentation comments cannot be applied to a function parameter's type", - ) - .span_label(self.token.span, "doc comments are not allowed here") - .emit(); - self.bump(); - } else if self.token == token::Pound && self.look_ahead(1, |t| { - *t == token::OpenDelim(token::Bracket) - }) { - let lo = self.token.span; - // Skip every token until next possible arg. - while self.token != token::CloseDelim(token::Bracket) { - self.bump(); - } - let sp = lo.to(self.token.span); - self.bump(); - self.struct_span_err( - sp, - "attributes cannot be applied to a function parameter's type", - ) - .span_label(sp, "attributes are not allowed here") - .emit(); - } - } - - crate fn parameter_without_type( - &mut self, - err: &mut DiagnosticBuilder<'_>, - pat: P, - require_name: bool, - is_self_allowed: bool, - is_trait_item: bool, - ) -> Option { - // If we find a pattern followed by an identifier, it could be an (incorrect) - // C-style parameter declaration. - if self.check_ident() && self.look_ahead(1, |t| { - *t == token::Comma || *t == token::CloseDelim(token::Paren) - }) { // `fn foo(String s) {}` - let ident = self.parse_ident().unwrap(); - let span = pat.span.with_hi(ident.span.hi()); - - err.span_suggestion( - span, - "declare the type after the parameter binding", - String::from(": "), - Applicability::HasPlaceholders, - ); - return Some(ident); - } else if let PatKind::Ident(_, ident, _) = pat.kind { - if require_name && ( - is_trait_item || - self.token == token::Comma || - self.token == token::Lt || - self.token == token::CloseDelim(token::Paren) - ) { // `fn foo(a, b) {}`, `fn foo(a, b) {}` or `fn foo(usize, usize) {}` - if is_self_allowed { - err.span_suggestion( - pat.span, - "if this is a `self` type, give it a parameter name", - format!("self: {}", ident), - Applicability::MaybeIncorrect, - ); - } - // Avoid suggesting that `fn foo(HashMap)` is fixed with a change to - // `fn foo(HashMap: TypeName)`. - if self.token != token::Lt { - err.span_suggestion( - pat.span, - "if this was a parameter name, give it a type", - format!("{}: TypeName", ident), - Applicability::HasPlaceholders, - ); - } - err.span_suggestion( - pat.span, - "if this is a type, explicitly ignore the parameter name", - format!("_: {}", ident), - Applicability::MachineApplicable, - ); - err.note("anonymous parameters are removed in the 2018 edition (see RFC 1685)"); - - // Don't attempt to recover by using the `X` in `X` as the parameter name. - return if self.token == token::Lt { None } else { Some(ident) }; - } - } - None - } - - crate fn recover_arg_parse(&mut self) -> PResult<'a, (P, P)> { - let pat = self.parse_pat(Some("argument name"))?; - self.expect(&token::Colon)?; - let ty = self.parse_ty()?; - - self.diagnostic() - .struct_span_err_with_code( - pat.span, - "patterns aren't allowed in methods without bodies", - DiagnosticId::Error("E0642".into()), - ) - .span_suggestion_short( - pat.span, - "give this argument a name or use an underscore to ignore it", - "_".to_owned(), - Applicability::MachineApplicable, - ) - .emit(); - - // Pretend the pattern is `_`, to avoid duplicate errors from AST validation. - let pat = P(Pat { - kind: PatKind::Wild, - span: pat.span, - id: ast::DUMMY_NODE_ID - }); - Ok((pat, ty)) - } - - crate fn recover_bad_self_param( - &mut self, - mut param: ast::Param, - is_trait_item: bool, - ) -> PResult<'a, ast::Param> { - let sp = param.pat.span; - param.ty.kind = TyKind::Err; - let mut err = self.struct_span_err(sp, "unexpected `self` parameter in function"); - if is_trait_item { - err.span_label(sp, "must be the first associated function parameter"); - } else { - err.span_label(sp, "not valid as function parameter"); - err.note("`self` is only valid as the first parameter of an associated function"); - } - err.emit(); - Ok(param) - } - - crate fn consume_block(&mut self, delim: token::DelimToken) { - let mut brace_depth = 0; - loop { - if self.eat(&token::OpenDelim(delim)) { - brace_depth += 1; - } else if self.eat(&token::CloseDelim(delim)) { - if brace_depth == 0 { - return; - } else { - brace_depth -= 1; - continue; - } - } else if self.token == token::Eof || self.eat(&token::CloseDelim(token::NoDelim)) { - return; - } else { - self.bump(); - } - } - } - - crate fn expected_expression_found(&self) -> DiagnosticBuilder<'a> { - let (span, msg) = match (&self.token.kind, self.subparser_name) { - (&token::Eof, Some(origin)) => { - let sp = self.sess.source_map().next_point(self.token.span); - (sp, format!("expected expression, found end of {}", origin)) - } - _ => (self.token.span, format!( - "expected expression, found {}", - self.this_token_descr(), - )), - }; - let mut err = self.struct_span_err(span, &msg); - let sp = self.sess.source_map().start_point(self.token.span); - if let Some(sp) = self.sess.ambiguous_block_expr_parse.borrow().get(&sp) { - self.sess.expr_parentheses_needed(&mut err, *sp, None); - } - err.span_label(span, "expected expression"); - err - } - - fn consume_tts( - &mut self, - mut acc: i64, // `i64` because malformed code can have more closing delims than opening. - // Not using `FxHashMap` due to `token::TokenKind: !Eq + !Hash`. - modifier: &[(token::TokenKind, i64)], - ) { - while acc > 0 { - if let Some((_, val)) = modifier.iter().find(|(t, _)| *t == self.token.kind) { - acc += *val; - } - if self.token.kind == token::Eof { - break; - } - self.bump(); - } - } - - /// Replace duplicated recovered parameters with `_` pattern to avoid unecessary errors. - /// - /// This is necessary because at this point we don't know whether we parsed a function with - /// anonymous parameters or a function with names but no types. In order to minimize - /// unecessary errors, we assume the parameters are in the shape of `fn foo(a, b, c)` where - /// the parameters are *names* (so we don't emit errors about not being able to find `b` in - /// the local scope), but if we find the same name multiple times, like in `fn foo(i8, i8)`, - /// we deduplicate them to not complain about duplicated parameter names. - crate fn deduplicate_recovered_params_names(&self, fn_inputs: &mut Vec) { - let mut seen_inputs = FxHashSet::default(); - for input in fn_inputs.iter_mut() { - let opt_ident = if let (PatKind::Ident(_, ident, _), TyKind::Err) = ( - &input.pat.kind, &input.ty.kind, - ) { - Some(*ident) - } else { - None - }; - if let Some(ident) = opt_ident { - if seen_inputs.contains(&ident) { - input.pat.kind = PatKind::Wild; - } - seen_inputs.insert(ident); - } - } - } -} diff --git a/src/libsyntax/parse/mod.rs b/src/libsyntax/parse/mod.rs index 6bcd9cd9b63..1eaee46a3c2 100644 --- a/src/libsyntax/parse/mod.rs +++ b/src/libsyntax/parse/mod.rs @@ -28,7 +28,6 @@ pub mod lexer; pub mod token; crate mod classify; -crate mod diagnostics; crate mod literal; crate mod unescape_error_reporting; diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs index b710fcff65b..6f55fd23e6e 100644 --- a/src/libsyntax/parse/parser.rs +++ b/src/libsyntax/parse/parser.rs @@ -10,7 +10,8 @@ mod path; pub use path::PathStyle; mod stmt; mod generics; -use super::diagnostics::Error; +mod diagnostics; +use diagnostics::Error; use crate::ast::{ self, DUMMY_NODE_ID, AttrStyle, Attribute, CrateSugar, Ident, diff --git a/src/libsyntax/parse/parser/diagnostics.rs b/src/libsyntax/parse/parser/diagnostics.rs new file mode 100644 index 00000000000..943838d9dda --- /dev/null +++ b/src/libsyntax/parse/parser/diagnostics.rs @@ -0,0 +1,1483 @@ +use crate::ast::{ + self, Param, BinOpKind, BindingMode, BlockCheckMode, Expr, ExprKind, Ident, Item, ItemKind, + Mutability, Pat, PatKind, PathSegment, QSelf, Ty, TyKind, +}; +use crate::parse::{SeqSep, PResult, Parser}; +use crate::parse::parser::{BlockMode, PathStyle, SemiColonMode, TokenType, TokenExpectType}; +use crate::parse::token::{self, TokenKind}; +use crate::print::pprust; +use crate::ptr::P; +use crate::symbol::{kw, sym}; +use crate::ThinVec; +use crate::util::parser::AssocOp; +use errors::{Applicability, DiagnosticBuilder, DiagnosticId, pluralise}; +use rustc_data_structures::fx::FxHashSet; +use syntax_pos::{Span, DUMMY_SP, MultiSpan, SpanSnippetError}; +use log::{debug, trace}; +use std::mem; + +const TURBOFISH: &'static str = "use `::<...>` instead of `<...>` to specify type arguments"; +/// Creates a placeholder argument. +crate fn dummy_arg(ident: Ident) -> Param { + let pat = P(Pat { + id: ast::DUMMY_NODE_ID, + kind: PatKind::Ident(BindingMode::ByValue(Mutability::Immutable), ident, None), + span: ident.span, + }); + let ty = Ty { + kind: TyKind::Err, + span: ident.span, + id: ast::DUMMY_NODE_ID + }; + Param { + attrs: ThinVec::default(), + id: ast::DUMMY_NODE_ID, + pat, + span: ident.span, + ty: P(ty), + is_placeholder: false, + } +} + +pub enum Error { + FileNotFoundForModule { + mod_name: String, + default_path: String, + secondary_path: String, + dir_path: String, + }, + DuplicatePaths { + mod_name: String, + default_path: String, + secondary_path: String, + }, + UselessDocComment, + InclusiveRangeWithNoEnd, +} + +impl Error { + fn span_err>( + self, + sp: S, + handler: &errors::Handler, + ) -> DiagnosticBuilder<'_> { + match self { + Error::FileNotFoundForModule { + ref mod_name, + ref default_path, + ref secondary_path, + ref dir_path, + } => { + let mut err = struct_span_err!( + handler, + sp, + E0583, + "file not found for module `{}`", + mod_name, + ); + err.help(&format!( + "name the file either {} or {} inside the directory \"{}\"", + default_path, + secondary_path, + dir_path, + )); + err + } + Error::DuplicatePaths { ref mod_name, ref default_path, ref secondary_path } => { + let mut err = struct_span_err!( + handler, + sp, + E0584, + "file for module `{}` found at both {} and {}", + mod_name, + default_path, + secondary_path, + ); + err.help("delete or rename one of them to remove the ambiguity"); + err + } + Error::UselessDocComment => { + let mut err = struct_span_err!( + handler, + sp, + E0585, + "found a documentation comment that doesn't document anything", + ); + err.help("doc comments must come before what they document, maybe a comment was \ + intended with `//`?"); + err + } + Error::InclusiveRangeWithNoEnd => { + let mut err = struct_span_err!( + handler, + sp, + E0586, + "inclusive range with no end", + ); + err.help("inclusive ranges must be bounded at the end (`..=b` or `a..=b`)"); + err + } + } + } +} + +pub trait RecoverQPath: Sized + 'static { + const PATH_STYLE: PathStyle = PathStyle::Expr; + fn to_ty(&self) -> Option>; + fn recovered(qself: Option, path: ast::Path) -> Self; +} + +impl RecoverQPath for Ty { + const PATH_STYLE: PathStyle = PathStyle::Type; + fn to_ty(&self) -> Option> { + Some(P(self.clone())) + } + fn recovered(qself: Option, path: ast::Path) -> Self { + Self { + span: path.span, + kind: TyKind::Path(qself, path), + id: ast::DUMMY_NODE_ID, + } + } +} + +impl RecoverQPath for Pat { + fn to_ty(&self) -> Option> { + self.to_ty() + } + fn recovered(qself: Option, path: ast::Path) -> Self { + Self { + span: path.span, + kind: PatKind::Path(qself, path), + id: ast::DUMMY_NODE_ID, + } + } +} + +impl RecoverQPath for Expr { + fn to_ty(&self) -> Option> { + self.to_ty() + } + fn recovered(qself: Option, path: ast::Path) -> Self { + Self { + span: path.span, + kind: ExprKind::Path(qself, path), + attrs: ThinVec::new(), + id: ast::DUMMY_NODE_ID, + } + } +} + +impl<'a> Parser<'a> { + pub fn fatal(&self, m: &str) -> DiagnosticBuilder<'a> { + self.span_fatal(self.token.span, m) + } + + pub fn span_fatal>(&self, sp: S, m: &str) -> DiagnosticBuilder<'a> { + self.sess.span_diagnostic.struct_span_fatal(sp, m) + } + + pub fn span_fatal_err>(&self, sp: S, err: Error) -> DiagnosticBuilder<'a> { + err.span_err(sp, self.diagnostic()) + } + + pub fn bug(&self, m: &str) -> ! { + self.sess.span_diagnostic.span_bug(self.token.span, m) + } + + pub fn span_err>(&self, sp: S, m: &str) { + self.sess.span_diagnostic.span_err(sp, m) + } + + crate fn struct_span_err>(&self, sp: S, m: &str) -> DiagnosticBuilder<'a> { + self.sess.span_diagnostic.struct_span_err(sp, m) + } + + crate fn span_bug>(&self, sp: S, m: &str) -> ! { + self.sess.span_diagnostic.span_bug(sp, m) + } + + crate fn diagnostic(&self) -> &'a errors::Handler { + &self.sess.span_diagnostic + } + + crate fn span_to_snippet(&self, span: Span) -> Result { + self.sess.source_map().span_to_snippet(span) + } + + crate fn expected_ident_found(&self) -> DiagnosticBuilder<'a> { + let mut err = self.struct_span_err( + self.token.span, + &format!("expected identifier, found {}", self.this_token_descr()), + ); + if let token::Ident(name, false) = self.token.kind { + if Ident::new(name, self.token.span).is_raw_guess() { + err.span_suggestion( + self.token.span, + "you can escape reserved keywords to use them as identifiers", + format!("r#{}", name), + Applicability::MaybeIncorrect, + ); + } + } + if let Some(token_descr) = self.token_descr() { + err.span_label(self.token.span, format!("expected identifier, found {}", token_descr)); + } else { + err.span_label(self.token.span, "expected identifier"); + if self.token == token::Comma && self.look_ahead(1, |t| t.is_ident()) { + err.span_suggestion( + self.token.span, + "remove this comma", + String::new(), + Applicability::MachineApplicable, + ); + } + } + err + } + + pub fn expected_one_of_not_found( + &mut self, + edible: &[TokenKind], + inedible: &[TokenKind], + ) -> PResult<'a, bool /* recovered */> { + fn tokens_to_string(tokens: &[TokenType]) -> String { + let mut i = tokens.iter(); + // This might be a sign we need a connect method on `Iterator`. + let b = i.next() + .map_or(String::new(), |t| t.to_string()); + i.enumerate().fold(b, |mut b, (i, a)| { + if tokens.len() > 2 && i == tokens.len() - 2 { + b.push_str(", or "); + } else if tokens.len() == 2 && i == tokens.len() - 2 { + b.push_str(" or "); + } else { + b.push_str(", "); + } + b.push_str(&a.to_string()); + b + }) + } + + let mut expected = edible.iter() + .map(|x| TokenType::Token(x.clone())) + .chain(inedible.iter().map(|x| TokenType::Token(x.clone()))) + .chain(self.expected_tokens.iter().cloned()) + .collect::>(); + expected.sort_by_cached_key(|x| x.to_string()); + expected.dedup(); + let expect = tokens_to_string(&expected[..]); + let actual = self.this_token_to_string(); + let (msg_exp, (label_sp, label_exp)) = if expected.len() > 1 { + let short_expect = if expected.len() > 6 { + format!("{} possible tokens", expected.len()) + } else { + expect.clone() + }; + (format!("expected one of {}, found `{}`", expect, actual), + (self.sess.source_map().next_point(self.prev_span), + format!("expected one of {} here", short_expect))) + } else if expected.is_empty() { + (format!("unexpected token: `{}`", actual), + (self.prev_span, "unexpected token after this".to_string())) + } else { + (format!("expected {}, found `{}`", expect, actual), + (self.sess.source_map().next_point(self.prev_span), + format!("expected {} here", expect))) + }; + self.last_unexpected_token_span = Some(self.token.span); + let mut err = self.fatal(&msg_exp); + if self.token.is_ident_named(sym::and) { + err.span_suggestion_short( + self.token.span, + "use `&&` instead of `and` for the boolean operator", + "&&".to_string(), + Applicability::MaybeIncorrect, + ); + } + if self.token.is_ident_named(sym::or) { + err.span_suggestion_short( + self.token.span, + "use `||` instead of `or` for the boolean operator", + "||".to_string(), + Applicability::MaybeIncorrect, + ); + } + let sp = if self.token == token::Eof { + // This is EOF; don't want to point at the following char, but rather the last token. + self.prev_span + } else { + label_sp + }; + match self.recover_closing_delimiter(&expected.iter().filter_map(|tt| match tt { + TokenType::Token(t) => Some(t.clone()), + _ => None, + }).collect::>(), err) { + Err(e) => err = e, + Ok(recovered) => { + return Ok(recovered); + } + } + + let is_semi_suggestable = expected.iter().any(|t| match t { + TokenType::Token(token::Semi) => true, // We expect a `;` here. + _ => false, + }) && ( // A `;` would be expected before the current keyword. + self.token.is_keyword(kw::Break) || + self.token.is_keyword(kw::Continue) || + self.token.is_keyword(kw::For) || + self.token.is_keyword(kw::If) || + self.token.is_keyword(kw::Let) || + self.token.is_keyword(kw::Loop) || + self.token.is_keyword(kw::Match) || + self.token.is_keyword(kw::Return) || + self.token.is_keyword(kw::While) + ); + let sm = self.sess.source_map(); + match (sm.lookup_line(self.token.span.lo()), sm.lookup_line(sp.lo())) { + (Ok(ref a), Ok(ref b)) if a.line != b.line && is_semi_suggestable => { + // The spans are in different lines, expected `;` and found `let` or `return`. + // High likelihood that it is only a missing `;`. + err.span_suggestion_short( + label_sp, + "a semicolon may be missing here", + ";".to_string(), + Applicability::MaybeIncorrect, + ); + err.emit(); + return Ok(true); + } + (Ok(ref a), Ok(ref b)) if a.line == b.line => { + // When the spans are in the same line, it means that the only content between + // them is whitespace, point at the found token in that case: + // + // X | () => { syntax error }; + // | ^^^^^ expected one of 8 possible tokens here + // + // instead of having: + // + // X | () => { syntax error }; + // | -^^^^^ unexpected token + // | | + // | expected one of 8 possible tokens here + err.span_label(self.token.span, label_exp); + } + _ if self.prev_span == syntax_pos::DUMMY_SP => { + // Account for macro context where the previous span might not be + // available to avoid incorrect output (#54841). + err.span_label(self.token.span, "unexpected token"); + } + _ => { + err.span_label(sp, label_exp); + err.span_label(self.token.span, "unexpected token"); + } + } + self.maybe_annotate_with_ascription(&mut err, false); + Err(err) + } + + pub fn maybe_annotate_with_ascription( + &self, + err: &mut DiagnosticBuilder<'_>, + maybe_expected_semicolon: bool, + ) { + if let Some((sp, likely_path)) = self.last_type_ascription { + let sm = self.sess.source_map(); + let next_pos = sm.lookup_char_pos(self.token.span.lo()); + let op_pos = sm.lookup_char_pos(sp.hi()); + + let allow_unstable = self.sess.unstable_features.is_nightly_build(); + + if likely_path { + err.span_suggestion( + sp, + "maybe write a path separator here", + "::".to_string(), + if allow_unstable { + Applicability::MaybeIncorrect + } else { + Applicability::MachineApplicable + }, + ); + } else if op_pos.line != next_pos.line && maybe_expected_semicolon { + err.span_suggestion( + sp, + "try using a semicolon", + ";".to_string(), + Applicability::MaybeIncorrect, + ); + } else if allow_unstable { + err.span_label(sp, "tried to parse a type due to this type ascription"); + } else { + err.span_label(sp, "tried to parse a type due to this"); + } + if allow_unstable { + // Give extra information about type ascription only if it's a nightly compiler. + err.note("`#![feature(type_ascription)]` lets you annotate an expression with a \ + type: `: `"); + err.note("for more information, see \ + https://github.com/rust-lang/rust/issues/23416"); + } + } + } + + /// Eats and discards tokens until one of `kets` is encountered. Respects token trees, + /// passes through any errors encountered. Used for error recovery. + crate fn eat_to_tokens(&mut self, kets: &[&TokenKind]) { + if let Err(ref mut err) = self.parse_seq_to_before_tokens( + kets, + SeqSep::none(), + TokenExpectType::Expect, + |p| Ok(p.parse_token_tree()), + ) { + err.cancel(); + } + } + + /// This function checks if there are trailing angle brackets and produces + /// a diagnostic to suggest removing them. + /// + /// ```ignore (diagnostic) + /// let _ = vec![1, 2, 3].into_iter().collect::>>>(); + /// ^^ help: remove extra angle brackets + /// ``` + crate fn check_trailing_angle_brackets(&mut self, segment: &PathSegment, end: TokenKind) { + // This function is intended to be invoked after parsing a path segment where there are two + // cases: + // + // 1. A specific token is expected after the path segment. + // eg. `x.foo(`, `x.foo::(` (parenthesis - method call), + // `Foo::`, or `Foo::::` (mod sep - continued path). + // 2. No specific token is expected after the path segment. + // eg. `x.foo` (field access) + // + // This function is called after parsing `.foo` and before parsing the token `end` (if + // present). This includes any angle bracket arguments, such as `.foo::` or + // `Foo::`. + + // We only care about trailing angle brackets if we previously parsed angle bracket + // arguments. This helps stop us incorrectly suggesting that extra angle brackets be + // removed in this case: + // + // `x.foo >> (3)` (where `x.foo` is a `u32` for example) + // + // This case is particularly tricky as we won't notice it just looking at the tokens - + // it will appear the same (in terms of upcoming tokens) as below (since the `::` will + // have already been parsed): + // + // `x.foo::>>(3)` + let parsed_angle_bracket_args = segment.args + .as_ref() + .map(|args| args.is_angle_bracketed()) + .unwrap_or(false); + + debug!( + "check_trailing_angle_brackets: parsed_angle_bracket_args={:?}", + parsed_angle_bracket_args, + ); + if !parsed_angle_bracket_args { + return; + } + + // Keep the span at the start so we can highlight the sequence of `>` characters to be + // removed. + let lo = self.token.span; + + // We need to look-ahead to see if we have `>` characters without moving the cursor forward + // (since we might have the field access case and the characters we're eating are + // actual operators and not trailing characters - ie `x.foo >> 3`). + let mut position = 0; + + // We can encounter `>` or `>>` tokens in any order, so we need to keep track of how + // many of each (so we can correctly pluralize our error messages) and continue to + // advance. + let mut number_of_shr = 0; + let mut number_of_gt = 0; + while self.look_ahead(position, |t| { + trace!("check_trailing_angle_brackets: t={:?}", t); + if *t == token::BinOp(token::BinOpToken::Shr) { + number_of_shr += 1; + true + } else if *t == token::Gt { + number_of_gt += 1; + true + } else { + false + } + }) { + position += 1; + } + + // If we didn't find any trailing `>` characters, then we have nothing to error about. + debug!( + "check_trailing_angle_brackets: number_of_gt={:?} number_of_shr={:?}", + number_of_gt, number_of_shr, + ); + if number_of_gt < 1 && number_of_shr < 1 { + return; + } + + // Finally, double check that we have our end token as otherwise this is the + // second case. + if self.look_ahead(position, |t| { + trace!("check_trailing_angle_brackets: t={:?}", t); + *t == end + }) { + // Eat from where we started until the end token so that parsing can continue + // as if we didn't have those extra angle brackets. + self.eat_to_tokens(&[&end]); + let span = lo.until(self.token.span); + + let total_num_of_gt = number_of_gt + number_of_shr * 2; + self.diagnostic() + .struct_span_err( + span, + &format!("unmatched angle bracket{}", pluralise!(total_num_of_gt)), + ) + .span_suggestion( + span, + &format!("remove extra angle bracket{}", pluralise!(total_num_of_gt)), + String::new(), + Applicability::MachineApplicable, + ) + .emit(); + } + } + + /// Produces an error if comparison operators are chained (RFC #558). + /// We only need to check the LHS, not the RHS, because all comparison ops have same + /// precedence (see `fn precedence`) and are left-associative (see `fn fixity`). + /// + /// This can also be hit if someone incorrectly writes `foo()` when they should have used + /// the turbofish (`foo::()`) syntax. We attempt some heuristic recovery if that is the + /// case. + /// + /// Keep in mind that given that `outer_op.is_comparison()` holds and comparison ops are left + /// associative we can infer that we have: + /// + /// outer_op + /// / \ + /// inner_op r2 + /// / \ + /// l1 r1 + crate fn check_no_chained_comparison( + &mut self, + lhs: &Expr, + outer_op: &AssocOp, + ) -> PResult<'a, Option>> { + debug_assert!( + outer_op.is_comparison(), + "check_no_chained_comparison: {:?} is not comparison", + outer_op, + ); + + let mk_err_expr = |this: &Self, span| { + Ok(Some(this.mk_expr(span, ExprKind::Err, ThinVec::new()))) + }; + + match lhs.kind { + ExprKind::Binary(op, _, _) if op.node.is_comparison() => { + // Respan to include both operators. + let op_span = op.span.to(self.prev_span); + let mut err = self.struct_span_err( + op_span, + "chained comparison operators require parentheses", + ); + + let suggest = |err: &mut DiagnosticBuilder<'_>| { + err.span_suggestion_verbose( + op_span.shrink_to_lo(), + TURBOFISH, + "::".to_string(), + Applicability::MaybeIncorrect, + ); + }; + + if op.node == BinOpKind::Lt && + *outer_op == AssocOp::Less || // Include `<` to provide this recommendation + *outer_op == AssocOp::Greater // even in a case like the following: + { // Foo>> + if *outer_op == AssocOp::Less { + let snapshot = self.clone(); + self.bump(); + // So far we have parsed `foo(` or `foo< bar >::`, so we rewind the + // parser and bail out. + mem::replace(self, snapshot.clone()); + } + } + return if token::ModSep == self.token.kind { + // We have some certainty that this was a bad turbofish at this point. + // `foo< bar >::` + suggest(&mut err); + + let snapshot = self.clone(); + self.bump(); // `::` + + // Consume the rest of the likely `foo::new()` or return at `foo`. + match self.parse_expr() { + Ok(_) => { + // 99% certain that the suggestion is correct, continue parsing. + err.emit(); + // FIXME: actually check that the two expressions in the binop are + // paths and resynthesize new fn call expression instead of using + // `ExprKind::Err` placeholder. + mk_err_expr(self, lhs.span.to(self.prev_span)) + } + Err(mut expr_err) => { + expr_err.cancel(); + // Not entirely sure now, but we bubble the error up with the + // suggestion. + mem::replace(self, snapshot); + Err(err) + } + } + } else if token::OpenDelim(token::Paren) == self.token.kind { + // We have high certainty that this was a bad turbofish at this point. + // `foo< bar >(` + suggest(&mut err); + // Consume the fn call arguments. + match self.consume_fn_args() { + Err(()) => Err(err), + Ok(()) => { + err.emit(); + // FIXME: actually check that the two expressions in the binop are + // paths and resynthesize new fn call expression instead of using + // `ExprKind::Err` placeholder. + mk_err_expr(self, lhs.span.to(self.prev_span)) + } + } + } else { + // All we know is that this is `foo < bar >` and *nothing* else. Try to + // be helpful, but don't attempt to recover. + err.help(TURBOFISH); + err.help("or use `(...)` if you meant to specify fn arguments"); + // These cases cause too many knock-down errors, bail out (#61329). + Err(err) + }; + } + err.emit(); + } + _ => {} + } + Ok(None) + } + + fn consume_fn_args(&mut self) -> Result<(), ()> { + let snapshot = self.clone(); + self.bump(); // `(` + + // Consume the fn call arguments. + let modifiers = [ + (token::OpenDelim(token::Paren), 1), + (token::CloseDelim(token::Paren), -1), + ]; + self.consume_tts(1, &modifiers[..]); + + if self.token.kind == token::Eof { + // Not entirely sure that what we consumed were fn arguments, rollback. + mem::replace(self, snapshot); + Err(()) + } else { + // 99% certain that the suggestion is correct, continue parsing. + Ok(()) + } + } + + crate fn maybe_report_ambiguous_plus( + &mut self, + allow_plus: bool, + impl_dyn_multi: bool, + ty: &Ty, + ) { + if !allow_plus && impl_dyn_multi { + let sum_with_parens = format!("({})", pprust::ty_to_string(&ty)); + self.struct_span_err(ty.span, "ambiguous `+` in a type") + .span_suggestion( + ty.span, + "use parentheses to disambiguate", + sum_with_parens, + Applicability::MachineApplicable, + ) + .emit(); + } + } + + pub(super) fn maybe_recover_from_bad_type_plus( + &mut self, + allow_plus: bool, + ty: &Ty, + ) -> PResult<'a, ()> { + // Do not add `+` to expected tokens. + if !allow_plus || !self.token.is_like_plus() { + return Ok(()); + } + + self.bump(); // `+` + let bounds = self.parse_generic_bounds(None)?; + let sum_span = ty.span.to(self.prev_span); + + let mut err = struct_span_err!( + self.sess.span_diagnostic, + sum_span, + E0178, + "expected a path on the left-hand side of `+`, not `{}`", + pprust::ty_to_string(ty) + ); + + match ty.kind { + TyKind::Rptr(ref lifetime, ref mut_ty) => { + let sum_with_parens = pprust::to_string(|s| { + s.s.word("&"); + s.print_opt_lifetime(lifetime); + s.print_mutability(mut_ty.mutbl); + s.popen(); + s.print_type(&mut_ty.ty); + s.print_type_bounds(" +", &bounds); + s.pclose() + }); + err.span_suggestion( + sum_span, + "try adding parentheses", + sum_with_parens, + Applicability::MachineApplicable, + ); + } + TyKind::Ptr(..) | TyKind::BareFn(..) => { + err.span_label(sum_span, "perhaps you forgot parentheses?"); + } + _ => { + err.span_label(sum_span, "expected a path"); + } + } + err.emit(); + Ok(()) + } + + /// Tries to recover from associated item paths like `[T]::AssocItem` / `(T, U)::AssocItem`. + /// Attempts to convert the base expression/pattern/type into a type, parses the `::AssocItem` + /// tail, and combines them into a `::AssocItem` expression/pattern/type. + crate fn maybe_recover_from_bad_qpath( + &mut self, + base: P, + allow_recovery: bool, + ) -> PResult<'a, P> { + // Do not add `::` to expected tokens. + if allow_recovery && self.token == token::ModSep { + if let Some(ty) = base.to_ty() { + return self.maybe_recover_from_bad_qpath_stage_2(ty.span, ty); + } + } + Ok(base) + } + + /// Given an already parsed `Ty`, parses the `::AssocItem` tail and + /// combines them into a `::AssocItem` expression/pattern/type. + crate fn maybe_recover_from_bad_qpath_stage_2( + &mut self, + ty_span: Span, + ty: P, + ) -> PResult<'a, P> { + self.expect(&token::ModSep)?; + + let mut path = ast::Path { + segments: Vec::new(), + span: DUMMY_SP, + }; + self.parse_path_segments(&mut path.segments, T::PATH_STYLE)?; + path.span = ty_span.to(self.prev_span); + + let ty_str = self + .span_to_snippet(ty_span) + .unwrap_or_else(|_| pprust::ty_to_string(&ty)); + self.diagnostic() + .struct_span_err(path.span, "missing angle brackets in associated item path") + .span_suggestion( + // This is a best-effort recovery. + path.span, + "try", + format!("<{}>::{}", ty_str, pprust::path_to_string(&path)), + Applicability::MaybeIncorrect, + ) + .emit(); + + let path_span = ty_span.shrink_to_hi(); // Use an empty path since `position == 0`. + Ok(P(T::recovered( + Some(QSelf { + ty, + path_span, + position: 0, + }), + path, + ))) + } + + crate fn maybe_consume_incorrect_semicolon(&mut self, items: &[P]) -> bool { + if self.eat(&token::Semi) { + let mut err = self.struct_span_err(self.prev_span, "expected item, found `;`"); + err.span_suggestion_short( + self.prev_span, + "remove this semicolon", + String::new(), + Applicability::MachineApplicable, + ); + if !items.is_empty() { + let previous_item = &items[items.len() - 1]; + let previous_item_kind_name = match previous_item.kind { + // Say "braced struct" because tuple-structs and + // braceless-empty-struct declarations do take a semicolon. + ItemKind::Struct(..) => Some("braced struct"), + ItemKind::Enum(..) => Some("enum"), + ItemKind::Trait(..) => Some("trait"), + ItemKind::Union(..) => Some("union"), + _ => None, + }; + if let Some(name) = previous_item_kind_name { + err.help(&format!( + "{} declarations are not followed by a semicolon", + name + )); + } + } + err.emit(); + true + } else { + false + } + } + + /// Creates a `DiagnosticBuilder` for an unexpected token `t` and tries to recover if it is a + /// closing delimiter. + pub fn unexpected_try_recover( + &mut self, + t: &TokenKind, + ) -> PResult<'a, bool /* recovered */> { + let token_str = pprust::token_kind_to_string(t); + let this_token_str = self.this_token_descr(); + let (prev_sp, sp) = match (&self.token.kind, self.subparser_name) { + // Point at the end of the macro call when reaching end of macro arguments. + (token::Eof, Some(_)) => { + let sp = self.sess.source_map().next_point(self.token.span); + (sp, sp) + } + // We don't want to point at the following span after DUMMY_SP. + // This happens when the parser finds an empty TokenStream. + _ if self.prev_span == DUMMY_SP => (self.token.span, self.token.span), + // EOF, don't want to point at the following char, but rather the last token. + (token::Eof, None) => (self.prev_span, self.token.span), + _ => (self.sess.source_map().next_point(self.prev_span), self.token.span), + }; + let msg = format!( + "expected `{}`, found {}", + token_str, + match (&self.token.kind, self.subparser_name) { + (token::Eof, Some(origin)) => format!("end of {}", origin), + _ => this_token_str, + }, + ); + let mut err = self.struct_span_err(sp, &msg); + let label_exp = format!("expected `{}`", token_str); + match self.recover_closing_delimiter(&[t.clone()], err) { + Err(e) => err = e, + Ok(recovered) => { + return Ok(recovered); + } + } + let sm = self.sess.source_map(); + match (sm.lookup_line(prev_sp.lo()), sm.lookup_line(sp.lo())) { + (Ok(ref a), Ok(ref b)) if a.line == b.line => { + // When the spans are in the same line, it means that the only content + // between them is whitespace, point only at the found token. + err.span_label(sp, label_exp); + } + _ => { + err.span_label(prev_sp, label_exp); + err.span_label(sp, "unexpected token"); + } + } + Err(err) + } + + crate fn parse_semi_or_incorrect_foreign_fn_body( + &mut self, + ident: &Ident, + extern_sp: Span, + ) -> PResult<'a, ()> { + if self.token != token::Semi { + // This might be an incorrect fn definition (#62109). + let parser_snapshot = self.clone(); + match self.parse_inner_attrs_and_block() { + Ok((_, body)) => { + self.struct_span_err(ident.span, "incorrect `fn` inside `extern` block") + .span_label(ident.span, "can't have a body") + .span_label(body.span, "this body is invalid here") + .span_label( + extern_sp, + "`extern` blocks define existing foreign functions and `fn`s \ + inside of them cannot have a body") + .help("you might have meant to write a function accessible through ffi, \ + which can be done by writing `extern fn` outside of the \ + `extern` block") + .note("for more information, visit \ + https://doc.rust-lang.org/std/keyword.extern.html") + .emit(); + } + Err(mut err) => { + err.cancel(); + mem::replace(self, parser_snapshot); + self.expect(&token::Semi)?; + } + } + } else { + self.bump(); + } + Ok(()) + } + + /// Consumes alternative await syntaxes like `await!()`, `await `, + /// `await? `, `await()`, and `await { }`. + crate fn parse_incorrect_await_syntax( + &mut self, + lo: Span, + await_sp: Span, + ) -> PResult<'a, (Span, ExprKind)> { + if self.token == token::Not { + // Handle `await!()`. + self.expect(&token::Not)?; + self.expect(&token::OpenDelim(token::Paren))?; + let expr = self.parse_expr()?; + self.expect(&token::CloseDelim(token::Paren))?; + let sp = self.error_on_incorrect_await(lo, self.prev_span, &expr, false); + return Ok((sp, ExprKind::Await(expr))) + } + + let is_question = self.eat(&token::Question); // Handle `await? `. + let expr = if self.token == token::OpenDelim(token::Brace) { + // Handle `await { }`. + // This needs to be handled separatedly from the next arm to avoid + // interpreting `await { }?` as `?.await`. + self.parse_block_expr( + None, + self.token.span, + BlockCheckMode::Default, + ThinVec::new(), + ) + } else { + self.parse_expr() + }.map_err(|mut err| { + err.span_label(await_sp, "while parsing this incorrect await expression"); + err + })?; + let sp = self.error_on_incorrect_await(lo, expr.span, &expr, is_question); + Ok((sp, ExprKind::Await(expr))) + } + + fn error_on_incorrect_await(&self, lo: Span, hi: Span, expr: &Expr, is_question: bool) -> Span { + let expr_str = self.span_to_snippet(expr.span) + .unwrap_or_else(|_| pprust::expr_to_string(&expr)); + let suggestion = format!("{}.await{}", expr_str, if is_question { "?" } else { "" }); + let sp = lo.to(hi); + let app = match expr.kind { + ExprKind::Try(_) => Applicability::MaybeIncorrect, // `await ?` + _ => Applicability::MachineApplicable, + }; + self.struct_span_err(sp, "incorrect use of `await`") + .span_suggestion(sp, "`await` is a postfix operation", suggestion, app) + .emit(); + sp + } + + /// If encountering `future.await()`, consumes and emits an error. + crate fn recover_from_await_method_call(&mut self) { + if self.token == token::OpenDelim(token::Paren) && + self.look_ahead(1, |t| t == &token::CloseDelim(token::Paren)) + { + // future.await() + let lo = self.token.span; + self.bump(); // ( + let sp = lo.to(self.token.span); + self.bump(); // ) + self.struct_span_err(sp, "incorrect use of `await`") + .span_suggestion( + sp, + "`await` is not a method call, remove the parentheses", + String::new(), + Applicability::MachineApplicable, + ).emit() + } + } + + /// Recovers a situation like `for ( $pat in $expr )` + /// and suggest writing `for $pat in $expr` instead. + /// + /// This should be called before parsing the `$block`. + crate fn recover_parens_around_for_head( + &mut self, + pat: P, + expr: &Expr, + begin_paren: Option, + ) -> P { + match (&self.token.kind, begin_paren) { + (token::CloseDelim(token::Paren), Some(begin_par_sp)) => { + self.bump(); + + let pat_str = self + // Remove the `(` from the span of the pattern: + .span_to_snippet(pat.span.trim_start(begin_par_sp).unwrap()) + .unwrap_or_else(|_| pprust::pat_to_string(&pat)); + + self.struct_span_err(self.prev_span, "unexpected closing `)`") + .span_label(begin_par_sp, "opening `(`") + .span_suggestion( + begin_par_sp.to(self.prev_span), + "remove parenthesis in `for` loop", + format!("{} in {}", pat_str, pprust::expr_to_string(&expr)), + // With e.g. `for (x) in y)` this would replace `(x) in y)` + // with `x) in y)` which is syntactically invalid. + // However, this is prevented before we get here. + Applicability::MachineApplicable, + ) + .emit(); + + // Unwrap `(pat)` into `pat` to avoid the `unused_parens` lint. + pat.and_then(|pat| match pat.kind { + PatKind::Paren(pat) => pat, + _ => P(pat), + }) + } + _ => pat, + } + } + + crate fn could_ascription_be_path(&self, node: &ast::ExprKind) -> bool { + self.token.is_ident() && + if let ast::ExprKind::Path(..) = node { true } else { false } && + !self.token.is_reserved_ident() && // v `foo:bar(baz)` + self.look_ahead(1, |t| t == &token::OpenDelim(token::Paren)) || + self.look_ahead(1, |t| t == &token::Lt) && // `foo:bar` + } + + crate fn recover_seq_parse_error( + &mut self, + delim: token::DelimToken, + lo: Span, + result: PResult<'a, P>, + ) -> P { + match result { + Ok(x) => x, + Err(mut err) => { + err.emit(); + // Recover from parse error. + self.consume_block(delim); + self.mk_expr(lo.to(self.prev_span), ExprKind::Err, ThinVec::new()) + } + } + } + + crate fn recover_closing_delimiter( + &mut self, + tokens: &[TokenKind], + mut err: DiagnosticBuilder<'a>, + ) -> PResult<'a, bool> { + let mut pos = None; + // We want to use the last closing delim that would apply. + for (i, unmatched) in self.unclosed_delims.iter().enumerate().rev() { + if tokens.contains(&token::CloseDelim(unmatched.expected_delim)) + && Some(self.token.span) > unmatched.unclosed_span + { + pos = Some(i); + } + } + match pos { + Some(pos) => { + // Recover and assume that the detected unclosed delimiter was meant for + // this location. Emit the diagnostic and act as if the delimiter was + // present for the parser's sake. + + // Don't attempt to recover from this unclosed delimiter more than once. + let unmatched = self.unclosed_delims.remove(pos); + let delim = TokenType::Token(token::CloseDelim(unmatched.expected_delim)); + + // We want to suggest the inclusion of the closing delimiter where it makes + // the most sense, which is immediately after the last token: + // + // {foo(bar {}} + // - ^ + // | | + // | help: `)` may belong here + // | + // unclosed delimiter + if let Some(sp) = unmatched.unclosed_span { + err.span_label(sp, "unclosed delimiter"); + } + err.span_suggestion_short( + self.sess.source_map().next_point(self.prev_span), + &format!("{} may belong here", delim.to_string()), + delim.to_string(), + Applicability::MaybeIncorrect, + ); + err.emit(); + self.expected_tokens.clear(); // reduce errors + Ok(true) + } + _ => Err(err), + } + } + + /// Recovers from `pub` keyword in places where it seems _reasonable_ but isn't valid. + crate fn eat_bad_pub(&mut self) { + if self.token.is_keyword(kw::Pub) { + match self.parse_visibility(false) { + Ok(vis) => { + self.diagnostic() + .struct_span_err(vis.span, "unnecessary visibility qualifier") + .span_label(vis.span, "`pub` not permitted here") + .emit(); + } + Err(mut err) => err.emit(), + } + } + } + + /// Eats tokens until we can be relatively sure we reached the end of the + /// statement. This is something of a best-effort heuristic. + /// + /// We terminate when we find an unmatched `}` (without consuming it). + crate fn recover_stmt(&mut self) { + self.recover_stmt_(SemiColonMode::Ignore, BlockMode::Ignore) + } + + /// If `break_on_semi` is `Break`, then we will stop consuming tokens after + /// finding (and consuming) a `;` outside of `{}` or `[]` (note that this is + /// approximate -- it can mean we break too early due to macros, but that + /// should only lead to sub-optimal recovery, not inaccurate parsing). + /// + /// If `break_on_block` is `Break`, then we will stop consuming tokens + /// after finding (and consuming) a brace-delimited block. + crate fn recover_stmt_(&mut self, break_on_semi: SemiColonMode, break_on_block: BlockMode) { + let mut brace_depth = 0; + let mut bracket_depth = 0; + let mut in_block = false; + debug!("recover_stmt_ enter loop (semi={:?}, block={:?})", + break_on_semi, break_on_block); + loop { + debug!("recover_stmt_ loop {:?}", self.token); + match self.token.kind { + token::OpenDelim(token::DelimToken::Brace) => { + brace_depth += 1; + self.bump(); + if break_on_block == BlockMode::Break && + brace_depth == 1 && + bracket_depth == 0 { + in_block = true; + } + } + token::OpenDelim(token::DelimToken::Bracket) => { + bracket_depth += 1; + self.bump(); + } + token::CloseDelim(token::DelimToken::Brace) => { + if brace_depth == 0 { + debug!("recover_stmt_ return - close delim {:?}", self.token); + break; + } + brace_depth -= 1; + self.bump(); + if in_block && bracket_depth == 0 && brace_depth == 0 { + debug!("recover_stmt_ return - block end {:?}", self.token); + break; + } + } + token::CloseDelim(token::DelimToken::Bracket) => { + bracket_depth -= 1; + if bracket_depth < 0 { + bracket_depth = 0; + } + self.bump(); + } + token::Eof => { + debug!("recover_stmt_ return - Eof"); + break; + } + token::Semi => { + self.bump(); + if break_on_semi == SemiColonMode::Break && + brace_depth == 0 && + bracket_depth == 0 { + debug!("recover_stmt_ return - Semi"); + break; + } + } + token::Comma if break_on_semi == SemiColonMode::Comma && + brace_depth == 0 && + bracket_depth == 0 => + { + debug!("recover_stmt_ return - Semi"); + break; + } + _ => { + self.bump() + } + } + } + } + + crate fn check_for_for_in_in_typo(&mut self, in_span: Span) { + if self.eat_keyword(kw::In) { + // a common typo: `for _ in in bar {}` + self.struct_span_err(self.prev_span, "expected iterable, found keyword `in`") + .span_suggestion_short( + in_span.until(self.prev_span), + "remove the duplicated `in`", + String::new(), + Applicability::MachineApplicable, + ) + .emit(); + } + } + + crate fn expected_semi_or_open_brace(&mut self) -> PResult<'a, T> { + let token_str = self.this_token_descr(); + let mut err = self.fatal(&format!("expected `;` or `{{`, found {}", token_str)); + err.span_label(self.token.span, "expected `;` or `{`"); + Err(err) + } + + crate fn eat_incorrect_doc_comment_for_param_type(&mut self) { + if let token::DocComment(_) = self.token.kind { + self.struct_span_err( + self.token.span, + "documentation comments cannot be applied to a function parameter's type", + ) + .span_label(self.token.span, "doc comments are not allowed here") + .emit(); + self.bump(); + } else if self.token == token::Pound && self.look_ahead(1, |t| { + *t == token::OpenDelim(token::Bracket) + }) { + let lo = self.token.span; + // Skip every token until next possible arg. + while self.token != token::CloseDelim(token::Bracket) { + self.bump(); + } + let sp = lo.to(self.token.span); + self.bump(); + self.struct_span_err( + sp, + "attributes cannot be applied to a function parameter's type", + ) + .span_label(sp, "attributes are not allowed here") + .emit(); + } + } + + crate fn parameter_without_type( + &mut self, + err: &mut DiagnosticBuilder<'_>, + pat: P, + require_name: bool, + is_self_allowed: bool, + is_trait_item: bool, + ) -> Option { + // If we find a pattern followed by an identifier, it could be an (incorrect) + // C-style parameter declaration. + if self.check_ident() && self.look_ahead(1, |t| { + *t == token::Comma || *t == token::CloseDelim(token::Paren) + }) { // `fn foo(String s) {}` + let ident = self.parse_ident().unwrap(); + let span = pat.span.with_hi(ident.span.hi()); + + err.span_suggestion( + span, + "declare the type after the parameter binding", + String::from(": "), + Applicability::HasPlaceholders, + ); + return Some(ident); + } else if let PatKind::Ident(_, ident, _) = pat.kind { + if require_name && ( + is_trait_item || + self.token == token::Comma || + self.token == token::Lt || + self.token == token::CloseDelim(token::Paren) + ) { // `fn foo(a, b) {}`, `fn foo(a, b) {}` or `fn foo(usize, usize) {}` + if is_self_allowed { + err.span_suggestion( + pat.span, + "if this is a `self` type, give it a parameter name", + format!("self: {}", ident), + Applicability::MaybeIncorrect, + ); + } + // Avoid suggesting that `fn foo(HashMap)` is fixed with a change to + // `fn foo(HashMap: TypeName)`. + if self.token != token::Lt { + err.span_suggestion( + pat.span, + "if this was a parameter name, give it a type", + format!("{}: TypeName", ident), + Applicability::HasPlaceholders, + ); + } + err.span_suggestion( + pat.span, + "if this is a type, explicitly ignore the parameter name", + format!("_: {}", ident), + Applicability::MachineApplicable, + ); + err.note("anonymous parameters are removed in the 2018 edition (see RFC 1685)"); + + // Don't attempt to recover by using the `X` in `X` as the parameter name. + return if self.token == token::Lt { None } else { Some(ident) }; + } + } + None + } + + crate fn recover_arg_parse(&mut self) -> PResult<'a, (P, P)> { + let pat = self.parse_pat(Some("argument name"))?; + self.expect(&token::Colon)?; + let ty = self.parse_ty()?; + + self.diagnostic() + .struct_span_err_with_code( + pat.span, + "patterns aren't allowed in methods without bodies", + DiagnosticId::Error("E0642".into()), + ) + .span_suggestion_short( + pat.span, + "give this argument a name or use an underscore to ignore it", + "_".to_owned(), + Applicability::MachineApplicable, + ) + .emit(); + + // Pretend the pattern is `_`, to avoid duplicate errors from AST validation. + let pat = P(Pat { + kind: PatKind::Wild, + span: pat.span, + id: ast::DUMMY_NODE_ID + }); + Ok((pat, ty)) + } + + crate fn recover_bad_self_param( + &mut self, + mut param: ast::Param, + is_trait_item: bool, + ) -> PResult<'a, ast::Param> { + let sp = param.pat.span; + param.ty.kind = TyKind::Err; + let mut err = self.struct_span_err(sp, "unexpected `self` parameter in function"); + if is_trait_item { + err.span_label(sp, "must be the first associated function parameter"); + } else { + err.span_label(sp, "not valid as function parameter"); + err.note("`self` is only valid as the first parameter of an associated function"); + } + err.emit(); + Ok(param) + } + + crate fn consume_block(&mut self, delim: token::DelimToken) { + let mut brace_depth = 0; + loop { + if self.eat(&token::OpenDelim(delim)) { + brace_depth += 1; + } else if self.eat(&token::CloseDelim(delim)) { + if brace_depth == 0 { + return; + } else { + brace_depth -= 1; + continue; + } + } else if self.token == token::Eof || self.eat(&token::CloseDelim(token::NoDelim)) { + return; + } else { + self.bump(); + } + } + } + + crate fn expected_expression_found(&self) -> DiagnosticBuilder<'a> { + let (span, msg) = match (&self.token.kind, self.subparser_name) { + (&token::Eof, Some(origin)) => { + let sp = self.sess.source_map().next_point(self.token.span); + (sp, format!("expected expression, found end of {}", origin)) + } + _ => (self.token.span, format!( + "expected expression, found {}", + self.this_token_descr(), + )), + }; + let mut err = self.struct_span_err(span, &msg); + let sp = self.sess.source_map().start_point(self.token.span); + if let Some(sp) = self.sess.ambiguous_block_expr_parse.borrow().get(&sp) { + self.sess.expr_parentheses_needed(&mut err, *sp, None); + } + err.span_label(span, "expected expression"); + err + } + + fn consume_tts( + &mut self, + mut acc: i64, // `i64` because malformed code can have more closing delims than opening. + // Not using `FxHashMap` due to `token::TokenKind: !Eq + !Hash`. + modifier: &[(token::TokenKind, i64)], + ) { + while acc > 0 { + if let Some((_, val)) = modifier.iter().find(|(t, _)| *t == self.token.kind) { + acc += *val; + } + if self.token.kind == token::Eof { + break; + } + self.bump(); + } + } + + /// Replace duplicated recovered parameters with `_` pattern to avoid unecessary errors. + /// + /// This is necessary because at this point we don't know whether we parsed a function with + /// anonymous parameters or a function with names but no types. In order to minimize + /// unecessary errors, we assume the parameters are in the shape of `fn foo(a, b, c)` where + /// the parameters are *names* (so we don't emit errors about not being able to find `b` in + /// the local scope), but if we find the same name multiple times, like in `fn foo(i8, i8)`, + /// we deduplicate them to not complain about duplicated parameter names. + crate fn deduplicate_recovered_params_names(&self, fn_inputs: &mut Vec) { + let mut seen_inputs = FxHashSet::default(); + for input in fn_inputs.iter_mut() { + let opt_ident = if let (PatKind::Ident(_, ident, _), TyKind::Err) = ( + &input.pat.kind, &input.ty.kind, + ) { + Some(*ident) + } else { + None + }; + if let Some(ident) = opt_ident { + if seen_inputs.contains(&ident) { + input.pat.kind = PatKind::Wild; + } + seen_inputs.insert(ident); + } + } + } +} diff --git a/src/libsyntax/parse/parser/expr.rs b/src/libsyntax/parse/parser/expr.rs index dd0fd834fb0..6e52a07c61d 100644 --- a/src/libsyntax/parse/parser/expr.rs +++ b/src/libsyntax/parse/parser/expr.rs @@ -1,6 +1,7 @@ use super::{Parser, PResult, Restrictions, PrevTokenKind, TokenType, PathStyle, BlockMode}; use super::{SemiColonMode, SeqSep, TokenExpectType}; use super::pat::{GateOr, PARAM_EXPECTED}; +use super::diagnostics::Error; use crate::parse::literal::LitError; @@ -12,7 +13,6 @@ use crate::ast::{ use crate::maybe_recover_from_interpolated_ty_qpath; use crate::parse::classify; use crate::parse::token::{self, Token, TokenKind}; -use crate::parse::diagnostics::Error; use crate::print::pprust; use crate::ptr::P; use crate::source_map::{self, Span}; diff --git a/src/libsyntax/parse/parser/item.rs b/src/libsyntax/parse/parser/item.rs index 08c624b5539..90517d4d770 100644 --- a/src/libsyntax/parse/parser/item.rs +++ b/src/libsyntax/parse/parser/item.rs @@ -1,4 +1,6 @@ use super::{Parser, PResult, PathStyle, SemiColonMode, BlockMode}; +use super::diagnostics::{Error, dummy_arg}; + use crate::maybe_whole; use crate::ptr::P; use crate::ast::{self, DUMMY_NODE_ID, Ident, Attribute, AttrStyle, AnonConst, Item, ItemKind}; @@ -10,7 +12,6 @@ use crate::ast::{Mac, MacDelimiter, Block, BindingMode, FnDecl, MethodSig, SelfK use crate::ext::base::DummyResult; use crate::parse::token; use crate::parse::parser::maybe_append; -use crate::parse::diagnostics::{Error, dummy_arg}; use crate::tokenstream::{TokenTree, TokenStream}; use crate::symbol::{kw, sym}; use crate::source_map::{self, respan, Span}; diff --git a/src/libsyntax/parse/parser/module.rs b/src/libsyntax/parse/parser/module.rs index 2d2fb487d7d..20bd189cf8f 100644 --- a/src/libsyntax/parse/parser/module.rs +++ b/src/libsyntax/parse/parser/module.rs @@ -1,11 +1,11 @@ use super::{Parser, PResult}; use super::item::ItemInfo; +use super::diagnostics::Error; use crate::attr; use crate::ast::{self, Ident, Attribute, ItemKind, Mod, Crate}; use crate::parse::{new_sub_parser_from_file, DirectoryOwnership}; use crate::parse::token::{self, TokenKind}; -use crate::parse::diagnostics::{Error}; use crate::source_map::{SourceMap, Span, DUMMY_SP, FileName}; use crate::symbol::sym; diff --git a/src/libsyntax/parse/parser/stmt.rs b/src/libsyntax/parse/parser/stmt.rs index 855b03ddd6f..c8d6b6ff9dd 100644 --- a/src/libsyntax/parse/parser/stmt.rs +++ b/src/libsyntax/parse/parser/stmt.rs @@ -2,6 +2,7 @@ use super::{Parser, PResult, Restrictions, PrevTokenKind, SemiColonMode, BlockMo use super::expr::LhsExpr; use super::path::PathStyle; use super::pat::GateOr; +use super::diagnostics::Error; use crate::ptr::P; use crate::{maybe_whole, ThinVec}; @@ -9,7 +10,6 @@ use crate::ast::{self, DUMMY_NODE_ID, Stmt, StmtKind, Local, Block, BlockCheckMo use crate::ast::{Attribute, AttrStyle, VisibilityKind, MacStmtStyle, Mac, MacDelimiter}; use crate::ext::base::DummyResult; use crate::parse::{classify, DirectoryOwnership}; -use crate::parse::diagnostics::Error; use crate::parse::token; use crate::source_map::{respan, Span}; use crate::symbol::{kw, sym}; -- cgit 1.4.1-3-g733a5 From bf02d49e848e331ba8bf3d14e3b3443bc68ab7f3 Mon Sep 17 00:00:00 2001 From: Mazdak Farrokhzad Date: Tue, 8 Oct 2019 12:59:59 +0200 Subject: move SeqSep to parser.rs --- src/libsyntax/parse/mod.rs | 26 +------------------------- src/libsyntax/parse/parser.rs | 26 +++++++++++++++++++++++++- src/libsyntax/parse/parser/attr.rs | 3 +-- src/libsyntax/parse/parser/diagnostics.rs | 6 ++++-- 4 files changed, 31 insertions(+), 30 deletions(-) (limited to 'src/libsyntax/parse/mod.rs') diff --git a/src/libsyntax/parse/mod.rs b/src/libsyntax/parse/mod.rs index 1eaee46a3c2..e6b794a6a99 100644 --- a/src/libsyntax/parse/mod.rs +++ b/src/libsyntax/parse/mod.rs @@ -2,7 +2,7 @@ use crate::ast; use crate::parse::parser::{Parser, emit_unclosed_delims}; -use crate::parse::token::{Nonterminal, TokenKind}; +use crate::parse::token::Nonterminal; use crate::tokenstream::{self, TokenStream, TokenTree}; use crate::print::pprust; use crate::sess::ParseSess; @@ -271,30 +271,6 @@ pub fn stream_to_parser_with_base_dir<'a>( Parser::new(sess, stream, Some(base_dir), true, false, None) } -/// A sequence separator. -pub struct SeqSep { - /// The separator token. - pub sep: Option, - /// `true` if a trailing separator is allowed. - pub trailing_sep_allowed: bool, -} - -impl SeqSep { - pub fn trailing_allowed(t: TokenKind) -> SeqSep { - SeqSep { - sep: Some(t), - trailing_sep_allowed: true, - } - } - - pub fn none() -> SeqSep { - SeqSep { - sep: None, - trailing_sep_allowed: false, - } - } -} - // NOTE(Centril): The following probably shouldn't be here but it acknowledges the // fact that architecturally, we are using parsing (read on below to understand why). diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs index 64ec943294a..79901177d18 100644 --- a/src/libsyntax/parse/parser.rs +++ b/src/libsyntax/parse/parser.rs @@ -15,7 +15,7 @@ use crate::ast::{ self, DUMMY_NODE_ID, AttrStyle, Attribute, CrateSugar, Ident, IsAsync, MacDelimiter, Mutability, StrStyle, Visibility, VisibilityKind, Unsafety, }; -use crate::parse::{PResult, Directory, DirectoryOwnership, SeqSep}; +use crate::parse::{PResult, Directory, DirectoryOwnership}; use crate::parse::lexer::UnmatchedBrace; use crate::parse::lexer::comments::{doc_comment_style, strip_doc_comment_decoration}; use crate::parse::token::{self, Token, TokenKind, DelimToken}; @@ -329,6 +329,30 @@ enum TokenExpectType { NoExpect, } +/// A sequence separator. +struct SeqSep { + /// The separator token. + sep: Option, + /// `true` if a trailing separator is allowed. + trailing_sep_allowed: bool, +} + +impl SeqSep { + fn trailing_allowed(t: TokenKind) -> SeqSep { + SeqSep { + sep: Some(t), + trailing_sep_allowed: true, + } + } + + fn none() -> SeqSep { + SeqSep { + sep: None, + trailing_sep_allowed: false, + } + } +} + impl<'a> Parser<'a> { pub fn new( sess: &'a ParseSess, diff --git a/src/libsyntax/parse/parser/attr.rs b/src/libsyntax/parse/parser/attr.rs index cfd10e443e9..463629de7a1 100644 --- a/src/libsyntax/parse/parser/attr.rs +++ b/src/libsyntax/parse/parser/attr.rs @@ -1,8 +1,7 @@ +use super::{SeqSep, PResult, Parser, TokenType, PathStyle}; use crate::attr; use crate::ast; -use crate::parse::{SeqSep, PResult}; use crate::parse::token::{self, Nonterminal, DelimToken}; -use crate::parse::parser::{Parser, TokenType, PathStyle}; use crate::tokenstream::{TokenStream, TokenTree}; use crate::source_map::Span; diff --git a/src/libsyntax/parse/parser/diagnostics.rs b/src/libsyntax/parse/parser/diagnostics.rs index 32a41bb0e27..6a4a6c0f16f 100644 --- a/src/libsyntax/parse/parser/diagnostics.rs +++ b/src/libsyntax/parse/parser/diagnostics.rs @@ -1,9 +1,11 @@ +use super::{ + BlockMode, PathStyle, SemiColonMode, TokenType, TokenExpectType, + SeqSep, PResult, Parser +}; use crate::ast::{ self, Param, BinOpKind, BindingMode, BlockCheckMode, Expr, ExprKind, Ident, Item, ItemKind, Mutability, Pat, PatKind, PathSegment, QSelf, Ty, TyKind, }; -use crate::parse::{SeqSep, PResult, Parser}; -use crate::parse::parser::{BlockMode, PathStyle, SemiColonMode, TokenType, TokenExpectType}; use crate::parse::token::{self, TokenKind}; use crate::print::pprust; use crate::ptr::P; -- cgit 1.4.1-3-g733a5