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| author | Jonathan Brouwer <jonathantbrouwer@gmail.com> | 2025-07-29 16:35:22 +0200 |
|---|---|---|
| committer | Jonathan Brouwer <jonathantbrouwer@gmail.com> | 2025-08-22 08:37:19 +0200 |
| commit | 21d31897794ed7fc7990de8e664d3c4ec511da7d (patch) | |
| tree | 46b719b15381fe0d89cec4e510a92423d8192dca /compiler/rustc_parse/src/validate_attr.rs | |
| parent | 8e3710ef31a0b2cdf5a1c2f3929b7735d1e28c20 (diff) | |
| download | rust-21d31897794ed7fc7990de8e664d3c4ec511da7d.tar.gz rust-21d31897794ed7fc7990de8e664d3c4ec511da7d.zip | |
Move validate_attr to `rustc_attr_parsing`
Diffstat (limited to 'compiler/rustc_parse/src/validate_attr.rs')
| -rw-r--r-- | compiler/rustc_parse/src/validate_attr.rs | 350 |
1 files changed, 0 insertions, 350 deletions
diff --git a/compiler/rustc_parse/src/validate_attr.rs b/compiler/rustc_parse/src/validate_attr.rs deleted file mode 100644 index 68ef6d6f32c..00000000000 --- a/compiler/rustc_parse/src/validate_attr.rs +++ /dev/null @@ -1,350 +0,0 @@ -//! Meta-syntax validation logic of attributes for post-expansion. - -use std::slice; - -use rustc_ast::token::Delimiter; -use rustc_ast::tokenstream::DelimSpan; -use rustc_ast::{ - self as ast, AttrArgs, Attribute, DelimArgs, MetaItem, MetaItemInner, MetaItemKind, NodeId, - Path, Safety, -}; -use rustc_attr_parsing::{AttributeParser, Late}; -use rustc_errors::{Applicability, DiagCtxtHandle, FatalError, PResult}; -use rustc_feature::{AttributeSafety, AttributeTemplate, BUILTIN_ATTRIBUTE_MAP, BuiltinAttribute}; -use rustc_session::errors::report_lit_error; -use rustc_session::lint::BuiltinLintDiag; -use rustc_session::lint::builtin::{ILL_FORMED_ATTRIBUTE_INPUT, UNSAFE_ATTR_OUTSIDE_UNSAFE}; -use rustc_session::parse::ParseSess; -use rustc_span::{Span, Symbol, sym}; - -use crate::{errors, parse_in}; - -pub fn check_attr(psess: &ParseSess, attr: &Attribute, id: NodeId) { - if attr.is_doc_comment() || attr.has_name(sym::cfg_trace) || attr.has_name(sym::cfg_attr_trace) - { - return; - } - - let builtin_attr_info = attr.ident().and_then(|ident| BUILTIN_ATTRIBUTE_MAP.get(&ident.name)); - - let builtin_attr_safety = builtin_attr_info.map(|x| x.safety); - check_attribute_safety(psess, builtin_attr_safety, attr, id); - - // Check input tokens for built-in and key-value attributes. - match builtin_attr_info { - // `rustc_dummy` doesn't have any restrictions specific to built-in attributes. - Some(BuiltinAttribute { name, template, .. }) if *name != sym::rustc_dummy => { - match parse_meta(psess, attr) { - // Don't check safety again, we just did that - Ok(meta) => { - check_builtin_meta_item(psess, &meta, attr.style, *name, *template, false) - } - Err(err) => { - err.emit(); - } - } - } - _ => { - let attr_item = attr.get_normal_item(); - if let AttrArgs::Eq { .. } = attr_item.args { - // All key-value attributes are restricted to meta-item syntax. - match parse_meta(psess, attr) { - Ok(_) => {} - Err(err) => { - err.emit(); - } - } - } - } - } -} - -pub fn parse_meta<'a>(psess: &'a ParseSess, attr: &Attribute) -> PResult<'a, MetaItem> { - let item = attr.get_normal_item(); - Ok(MetaItem { - unsafety: item.unsafety, - span: attr.span, - path: item.path.clone(), - kind: match &item.args { - AttrArgs::Empty => MetaItemKind::Word, - AttrArgs::Delimited(DelimArgs { dspan, delim, tokens }) => { - check_meta_bad_delim(psess, *dspan, *delim); - let nmis = - parse_in(psess, tokens.clone(), "meta list", |p| p.parse_meta_seq_top())?; - MetaItemKind::List(nmis) - } - AttrArgs::Eq { expr, .. } => { - if let ast::ExprKind::Lit(token_lit) = expr.kind { - let res = ast::MetaItemLit::from_token_lit(token_lit, expr.span); - let res = match res { - Ok(lit) => { - if token_lit.suffix.is_some() { - let mut err = psess.dcx().struct_span_err( - expr.span, - "suffixed literals are not allowed in attributes", - ); - err.help( - "instead of using a suffixed literal (`1u8`, `1.0f32`, etc.), \ - use an unsuffixed version (`1`, `1.0`, etc.)", - ); - return Err(err); - } else { - MetaItemKind::NameValue(lit) - } - } - Err(err) => { - let guar = report_lit_error(psess, err, token_lit, expr.span); - let lit = ast::MetaItemLit { - symbol: token_lit.symbol, - suffix: token_lit.suffix, - kind: ast::LitKind::Err(guar), - span: expr.span, - }; - MetaItemKind::NameValue(lit) - } - }; - res - } else { - // Example cases: - // - `#[foo = 1+1]`: results in `ast::ExprKind::Binary`. - // - `#[foo = include_str!("nonexistent-file.rs")]`: - // results in `ast::ExprKind::Err`. In that case we delay - // the error because an earlier error will have already - // been reported. - let msg = "attribute value must be a literal"; - let mut err = psess.dcx().struct_span_err(expr.span, msg); - if let ast::ExprKind::Err(_) = expr.kind { - err.downgrade_to_delayed_bug(); - } - return Err(err); - } - } - }, - }) -} - -fn check_meta_bad_delim(psess: &ParseSess, span: DelimSpan, delim: Delimiter) { - if let Delimiter::Parenthesis = delim { - return; - } - psess.dcx().emit_err(errors::MetaBadDelim { - span: span.entire(), - sugg: errors::MetaBadDelimSugg { open: span.open, close: span.close }, - }); -} - -pub(super) fn check_cfg_attr_bad_delim(psess: &ParseSess, span: DelimSpan, delim: Delimiter) { - if let Delimiter::Parenthesis = delim { - return; - } - psess.dcx().emit_err(errors::CfgAttrBadDelim { - span: span.entire(), - sugg: errors::MetaBadDelimSugg { open: span.open, close: span.close }, - }); -} - -/// Checks that the given meta-item is compatible with this `AttributeTemplate`. -fn is_attr_template_compatible(template: &AttributeTemplate, meta: &ast::MetaItemKind) -> bool { - let is_one_allowed_subword = |items: &[MetaItemInner]| match items { - [item] => item.is_word() && template.one_of.iter().any(|&word| item.has_name(word)), - _ => false, - }; - match meta { - MetaItemKind::Word => template.word, - MetaItemKind::List(items) => template.list.is_some() || is_one_allowed_subword(items), - MetaItemKind::NameValue(lit) if lit.kind.is_str() => template.name_value_str.is_some(), - MetaItemKind::NameValue(..) => false, - } -} - -pub fn check_attribute_safety( - psess: &ParseSess, - builtin_attr_safety: Option<AttributeSafety>, - attr: &Attribute, - id: NodeId, -) { - let attr_item = attr.get_normal_item(); - match (builtin_attr_safety, attr_item.unsafety) { - // - Unsafe builtin attribute - // - User wrote `#[unsafe(..)]`, which is permitted on any edition - (Some(AttributeSafety::Unsafe { .. }), Safety::Unsafe(..)) => { - // OK - } - - // - Unsafe builtin attribute - // - User did not write `#[unsafe(..)]` - (Some(AttributeSafety::Unsafe { unsafe_since }), Safety::Default) => { - let path_span = attr_item.path.span; - - // If the `attr_item`'s span is not from a macro, then just suggest - // wrapping it in `unsafe(...)`. Otherwise, we suggest putting the - // `unsafe(`, `)` right after and right before the opening and closing - // square bracket respectively. - let diag_span = attr_item.span(); - - // Attributes can be safe in earlier editions, and become unsafe in later ones. - // - // Use the span of the attribute's name to determine the edition: the span of the - // attribute as a whole may be inaccurate if it was emitted by a macro. - // - // See https://github.com/rust-lang/rust/issues/142182. - let emit_error = match unsafe_since { - None => true, - Some(unsafe_since) => path_span.edition() >= unsafe_since, - }; - - if emit_error { - psess.dcx().emit_err(errors::UnsafeAttrOutsideUnsafe { - span: path_span, - suggestion: errors::UnsafeAttrOutsideUnsafeSuggestion { - left: diag_span.shrink_to_lo(), - right: diag_span.shrink_to_hi(), - }, - }); - } else { - psess.buffer_lint( - UNSAFE_ATTR_OUTSIDE_UNSAFE, - path_span, - id, - BuiltinLintDiag::UnsafeAttrOutsideUnsafe { - attribute_name_span: path_span, - sugg_spans: (diag_span.shrink_to_lo(), diag_span.shrink_to_hi()), - }, - ); - } - } - - // - Normal builtin attribute, or any non-builtin attribute - // - All non-builtin attributes are currently considered safe; writing `#[unsafe(..)]` is - // not permitted on non-builtin attributes or normal builtin attributes - (Some(AttributeSafety::Normal) | None, Safety::Unsafe(unsafe_span)) => { - psess.dcx().emit_err(errors::InvalidAttrUnsafe { - span: unsafe_span, - name: attr_item.path.clone(), - }); - } - - // - Normal builtin attribute - // - No explicit `#[unsafe(..)]` written. - (Some(AttributeSafety::Normal), Safety::Default) => { - // OK - } - - // - Non-builtin attribute - // - No explicit `#[unsafe(..)]` written. - (None, Safety::Default) => { - // OK - } - - ( - Some(AttributeSafety::Unsafe { .. } | AttributeSafety::Normal) | None, - Safety::Safe(..), - ) => { - psess.dcx().span_delayed_bug( - attr_item.span(), - "`check_attribute_safety` does not expect `Safety::Safe` on attributes", - ); - } - } -} - -// Called by `check_builtin_meta_item` and code that manually denies -// `unsafe(...)` in `cfg` -pub fn deny_builtin_meta_unsafety(diag: DiagCtxtHandle<'_>, unsafety: Safety, name: &Path) { - // This only supports denying unsafety right now - making builtin attributes - // support unsafety will requite us to thread the actual `Attribute` through - // for the nice diagnostics. - if let Safety::Unsafe(unsafe_span) = unsafety { - diag.emit_err(errors::InvalidAttrUnsafe { span: unsafe_span, name: name.clone() }); - } -} - -pub fn check_builtin_meta_item( - psess: &ParseSess, - meta: &MetaItem, - style: ast::AttrStyle, - name: Symbol, - template: AttributeTemplate, - deny_unsafety: bool, -) { - if !is_attr_template_compatible(&template, &meta.kind) { - // attrs with new parsers are locally validated so excluded here - if AttributeParser::<Late>::is_parsed_attribute(slice::from_ref(&name)) { - return; - } - emit_malformed_attribute(psess, style, meta.span, name, template); - } - - if deny_unsafety { - deny_builtin_meta_unsafety(psess.dcx(), meta.unsafety, &meta.path); - } -} - -fn emit_malformed_attribute( - psess: &ParseSess, - style: ast::AttrStyle, - span: Span, - name: Symbol, - template: AttributeTemplate, -) { - // Some of previously accepted forms were used in practice, - // report them as warnings for now. - let should_warn = |name| matches!(name, sym::doc | sym::link | sym::test | sym::bench); - - let error_msg = format!("malformed `{name}` attribute input"); - let mut suggestions = vec![]; - let inner = if style == ast::AttrStyle::Inner { "!" } else { "" }; - if template.word { - suggestions.push(format!("#{inner}[{name}]")); - } - if let Some(descr) = template.list { - for descr in descr { - suggestions.push(format!("#{inner}[{name}({descr})]")); - } - } - suggestions.extend(template.one_of.iter().map(|&word| format!("#{inner}[{name}({word})]"))); - if let Some(descr) = template.name_value_str { - for descr in descr { - suggestions.push(format!("#{inner}[{name} = \"{descr}\"]")); - } - } - if should_warn(name) { - psess.buffer_lint( - ILL_FORMED_ATTRIBUTE_INPUT, - span, - ast::CRATE_NODE_ID, - BuiltinLintDiag::IllFormedAttributeInput { - suggestions: suggestions.clone(), - docs: template.docs, - }, - ); - } else { - suggestions.sort(); - let mut err = psess.dcx().struct_span_err(span, error_msg).with_span_suggestions( - span, - if suggestions.len() == 1 { - "must be of the form" - } else { - "the following are the possible correct uses" - }, - suggestions, - Applicability::HasPlaceholders, - ); - if let Some(link) = template.docs { - err.note(format!("for more information, visit <{link}>")); - } - err.emit(); - } -} - -pub fn emit_fatal_malformed_builtin_attribute( - psess: &ParseSess, - attr: &Attribute, - name: Symbol, -) -> ! { - let template = BUILTIN_ATTRIBUTE_MAP.get(&name).expect("builtin attr defined").template; - emit_malformed_attribute(psess, attr.style, attr.span, name, template); - // This is fatal, otherwise it will likely cause a cascade of other errors - // (and an error here is expected to be very rare). - FatalError.raise() -} |
