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Diffstat (limited to 'src/libsyntax/ext/base.rs')
| -rw-r--r-- | src/libsyntax/ext/base.rs | 1187 |
1 files changed, 0 insertions, 1187 deletions
diff --git a/src/libsyntax/ext/base.rs b/src/libsyntax/ext/base.rs deleted file mode 100644 index 583fb3f7701..00000000000 --- a/src/libsyntax/ext/base.rs +++ /dev/null @@ -1,1187 +0,0 @@ -use crate::ast::{self, NodeId, Attribute, Name, PatKind}; -use crate::attr::{self, HasAttrs, Stability, Deprecation}; -use crate::source_map::SourceMap; -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::token; -use crate::ptr::P; -use crate::symbol::{kw, sym, Ident, Symbol}; -use crate::{ThinVec, MACRO_ARGUMENTS}; -use crate::tokenstream::{self, TokenStream}; -use crate::visit::Visitor; - -use errors::{DiagnosticBuilder, DiagnosticId}; -use smallvec::{smallvec, SmallVec}; -use syntax_pos::{FileName, Span, MultiSpan, DUMMY_SP}; -use syntax_pos::hygiene::{AstPass, ExpnData, ExpnKind}; - -use rustc_data_structures::fx::FxHashMap; -use rustc_data_structures::sync::{self, Lrc}; -use std::iter; -use std::path::PathBuf; -use std::rc::Rc; -use std::default::Default; - -pub use syntax_pos::hygiene::MacroKind; - -#[derive(Debug,Clone)] -pub enum Annotatable { - Item(P<ast::Item>), - TraitItem(P<ast::TraitItem>), - ImplItem(P<ast::ImplItem>), - ForeignItem(P<ast::ForeignItem>), - Stmt(P<ast::Stmt>), - Expr(P<ast::Expr>), - Arm(ast::Arm), - Field(ast::Field), - FieldPat(ast::FieldPat), - GenericParam(ast::GenericParam), - Param(ast::Param), - StructField(ast::StructField), - Variant(ast::Variant), -} - -impl HasAttrs for Annotatable { - fn attrs(&self) -> &[Attribute] { - match *self { - Annotatable::Item(ref item) => &item.attrs, - Annotatable::TraitItem(ref trait_item) => &trait_item.attrs, - Annotatable::ImplItem(ref impl_item) => &impl_item.attrs, - Annotatable::ForeignItem(ref foreign_item) => &foreign_item.attrs, - Annotatable::Stmt(ref stmt) => stmt.attrs(), - Annotatable::Expr(ref expr) => &expr.attrs, - Annotatable::Arm(ref arm) => &arm.attrs, - Annotatable::Field(ref field) => &field.attrs, - Annotatable::FieldPat(ref fp) => &fp.attrs, - Annotatable::GenericParam(ref gp) => &gp.attrs, - Annotatable::Param(ref p) => &p.attrs, - Annotatable::StructField(ref sf) => &sf.attrs, - Annotatable::Variant(ref v) => &v.attrs(), - } - } - - fn visit_attrs<F: FnOnce(&mut Vec<Attribute>)>(&mut self, f: F) { - match self { - Annotatable::Item(item) => item.visit_attrs(f), - Annotatable::TraitItem(trait_item) => trait_item.visit_attrs(f), - Annotatable::ImplItem(impl_item) => impl_item.visit_attrs(f), - Annotatable::ForeignItem(foreign_item) => foreign_item.visit_attrs(f), - Annotatable::Stmt(stmt) => stmt.visit_attrs(f), - Annotatable::Expr(expr) => expr.visit_attrs(f), - Annotatable::Arm(arm) => arm.visit_attrs(f), - Annotatable::Field(field) => field.visit_attrs(f), - Annotatable::FieldPat(fp) => fp.visit_attrs(f), - Annotatable::GenericParam(gp) => gp.visit_attrs(f), - Annotatable::Param(p) => p.visit_attrs(f), - Annotatable::StructField(sf) => sf.visit_attrs(f), - Annotatable::Variant(v) => v.visit_attrs(f), - } - } -} - -impl Annotatable { - pub fn span(&self) -> Span { - match *self { - Annotatable::Item(ref item) => item.span, - Annotatable::TraitItem(ref trait_item) => trait_item.span, - Annotatable::ImplItem(ref impl_item) => impl_item.span, - Annotatable::ForeignItem(ref foreign_item) => foreign_item.span, - Annotatable::Stmt(ref stmt) => stmt.span, - Annotatable::Expr(ref expr) => expr.span, - Annotatable::Arm(ref arm) => arm.span, - Annotatable::Field(ref field) => field.span, - Annotatable::FieldPat(ref fp) => fp.pat.span, - Annotatable::GenericParam(ref gp) => gp.ident.span, - Annotatable::Param(ref p) => p.span, - Annotatable::StructField(ref sf) => sf.span, - Annotatable::Variant(ref v) => v.span, - } - } - - pub fn visit_with<'a, V: Visitor<'a>>(&'a self, visitor: &mut V) { - match self { - Annotatable::Item(item) => visitor.visit_item(item), - Annotatable::TraitItem(trait_item) => visitor.visit_trait_item(trait_item), - Annotatable::ImplItem(impl_item) => visitor.visit_impl_item(impl_item), - Annotatable::ForeignItem(foreign_item) => visitor.visit_foreign_item(foreign_item), - Annotatable::Stmt(stmt) => visitor.visit_stmt(stmt), - Annotatable::Expr(expr) => visitor.visit_expr(expr), - Annotatable::Arm(arm) => visitor.visit_arm(arm), - Annotatable::Field(field) => visitor.visit_field(field), - Annotatable::FieldPat(fp) => visitor.visit_field_pattern(fp), - Annotatable::GenericParam(gp) => visitor.visit_generic_param(gp), - Annotatable::Param(p) => visitor.visit_param(p), - Annotatable::StructField(sf) =>visitor.visit_struct_field(sf), - Annotatable::Variant(v) => visitor.visit_variant(v), - } - } - - pub fn expect_item(self) -> P<ast::Item> { - match self { - Annotatable::Item(i) => i, - _ => panic!("expected Item") - } - } - - pub fn map_item_or<F, G>(self, mut f: F, mut or: G) -> Annotatable - where F: FnMut(P<ast::Item>) -> P<ast::Item>, - G: FnMut(Annotatable) -> Annotatable - { - match self { - Annotatable::Item(i) => Annotatable::Item(f(i)), - _ => or(self) - } - } - - pub fn expect_trait_item(self) -> ast::TraitItem { - match self { - Annotatable::TraitItem(i) => i.into_inner(), - _ => panic!("expected Item") - } - } - - pub fn expect_impl_item(self) -> ast::ImplItem { - match self { - Annotatable::ImplItem(i) => i.into_inner(), - _ => panic!("expected Item") - } - } - - pub fn expect_foreign_item(self) -> ast::ForeignItem { - match self { - Annotatable::ForeignItem(i) => i.into_inner(), - _ => panic!("expected foreign item") - } - } - - pub fn expect_stmt(self) -> ast::Stmt { - match self { - Annotatable::Stmt(stmt) => stmt.into_inner(), - _ => panic!("expected statement"), - } - } - - pub fn expect_expr(self) -> P<ast::Expr> { - match self { - Annotatable::Expr(expr) => expr, - _ => panic!("expected expression"), - } - } - - pub fn expect_arm(self) -> ast::Arm { - match self { - Annotatable::Arm(arm) => arm, - _ => panic!("expected match arm") - } - } - - pub fn expect_field(self) -> ast::Field { - match self { - Annotatable::Field(field) => field, - _ => panic!("expected field") - } - } - - pub fn expect_field_pattern(self) -> ast::FieldPat { - match self { - Annotatable::FieldPat(fp) => fp, - _ => panic!("expected field pattern") - } - } - - pub fn expect_generic_param(self) -> ast::GenericParam { - match self { - Annotatable::GenericParam(gp) => gp, - _ => panic!("expected generic parameter") - } - } - - pub fn expect_param(self) -> ast::Param { - match self { - Annotatable::Param(param) => param, - _ => panic!("expected parameter") - } - } - - pub fn expect_struct_field(self) -> ast::StructField { - match self { - Annotatable::StructField(sf) => sf, - _ => panic!("expected struct field") - } - } - - pub fn expect_variant(self) -> ast::Variant { - match self { - Annotatable::Variant(v) => v, - _ => panic!("expected variant") - } - } - - pub fn derive_allowed(&self) -> bool { - match *self { - Annotatable::Item(ref item) => match item.kind { - ast::ItemKind::Struct(..) | - ast::ItemKind::Enum(..) | - ast::ItemKind::Union(..) => true, - _ => false, - }, - _ => false, - } - } -} - -// `meta_item` is the annotation, and `item` is the item being modified. -// FIXME Decorators should follow the same pattern too. -pub trait MultiItemModifier { - fn expand(&self, - ecx: &mut ExtCtxt<'_>, - span: Span, - meta_item: &ast::MetaItem, - item: Annotatable) - -> Vec<Annotatable>; -} - -impl<F, T> MultiItemModifier for F - where F: Fn(&mut ExtCtxt<'_>, Span, &ast::MetaItem, Annotatable) -> T, - T: Into<Vec<Annotatable>>, -{ - fn expand(&self, - ecx: &mut ExtCtxt<'_>, - span: Span, - meta_item: &ast::MetaItem, - item: Annotatable) - -> Vec<Annotatable> { - (*self)(ecx, span, meta_item, item).into() - } -} - -impl Into<Vec<Annotatable>> for Annotatable { - fn into(self) -> Vec<Annotatable> { - vec![self] - } -} - -pub trait ProcMacro { - fn expand<'cx>(&self, - ecx: &'cx mut ExtCtxt<'_>, - span: Span, - ts: TokenStream) - -> TokenStream; -} - -impl<F> ProcMacro for F - where F: Fn(TokenStream) -> TokenStream -{ - fn expand<'cx>(&self, - _ecx: &'cx mut ExtCtxt<'_>, - _span: Span, - ts: TokenStream) - -> TokenStream { - // FIXME setup implicit context in TLS before calling self. - (*self)(ts) - } -} - -pub trait AttrProcMacro { - fn expand<'cx>(&self, - ecx: &'cx mut ExtCtxt<'_>, - span: Span, - annotation: TokenStream, - annotated: TokenStream) - -> TokenStream; -} - -impl<F> AttrProcMacro for F - where F: Fn(TokenStream, TokenStream) -> TokenStream -{ - fn expand<'cx>(&self, - _ecx: &'cx mut ExtCtxt<'_>, - _span: Span, - annotation: TokenStream, - annotated: TokenStream) - -> TokenStream { - // FIXME setup implicit context in TLS before calling self. - (*self)(annotation, annotated) - } -} - -/// Represents a thing that maps token trees to Macro Results -pub trait TTMacroExpander { - fn expand<'cx>( - &self, - ecx: &'cx mut ExtCtxt<'_>, - span: Span, - input: TokenStream, - ) -> Box<dyn MacResult+'cx>; -} - -pub type MacroExpanderFn = - for<'cx> fn(&'cx mut ExtCtxt<'_>, Span, TokenStream) - -> Box<dyn MacResult+'cx>; - -impl<F> TTMacroExpander for F - where F: for<'cx> Fn(&'cx mut ExtCtxt<'_>, Span, TokenStream) - -> Box<dyn MacResult+'cx> -{ - fn expand<'cx>( - &self, - ecx: &'cx mut ExtCtxt<'_>, - span: Span, - mut input: TokenStream, - ) -> Box<dyn MacResult+'cx> { - struct AvoidInterpolatedIdents; - - impl MutVisitor for AvoidInterpolatedIdents { - fn visit_tt(&mut self, tt: &mut tokenstream::TokenTree) { - if let tokenstream::TokenTree::Token(token) = tt { - if let token::Interpolated(nt) = &token.kind { - if let token::NtIdent(ident, is_raw) = **nt { - *tt = tokenstream::TokenTree::token( - token::Ident(ident.name, is_raw), ident.span - ); - } - } - } - mut_visit::noop_visit_tt(tt, self) - } - - fn visit_mac(&mut self, mac: &mut ast::Mac) { - mut_visit::noop_visit_mac(mac, self) - } - } - AvoidInterpolatedIdents.visit_tts(&mut input); - (*self)(ecx, span, input) - } -} - -// Use a macro because forwarding to a simple function has type system issues -macro_rules! make_stmts_default { - ($me:expr) => { - $me.make_expr().map(|e| smallvec![ast::Stmt { - id: ast::DUMMY_NODE_ID, - span: e.span, - kind: ast::StmtKind::Expr(e), - }]) - } -} - -/// The result of a macro expansion. The return values of the various -/// methods are spliced into the AST at the callsite of the macro. -pub trait MacResult { - /// Creates an expression. - fn make_expr(self: Box<Self>) -> Option<P<ast::Expr>> { - None - } - /// Creates zero or more items. - fn make_items(self: Box<Self>) -> Option<SmallVec<[P<ast::Item>; 1]>> { - None - } - - /// Creates zero or more impl items. - fn make_impl_items(self: Box<Self>) -> Option<SmallVec<[ast::ImplItem; 1]>> { - None - } - - /// Creates zero or more trait items. - fn make_trait_items(self: Box<Self>) -> Option<SmallVec<[ast::TraitItem; 1]>> { - None - } - - /// Creates zero or more items in an `extern {}` block - fn make_foreign_items(self: Box<Self>) -> Option<SmallVec<[ast::ForeignItem; 1]>> { None } - - /// Creates a pattern. - fn make_pat(self: Box<Self>) -> Option<P<ast::Pat>> { - None - } - - /// Creates zero or more statements. - /// - /// By default this attempts to create an expression statement, - /// returning None if that fails. - fn make_stmts(self: Box<Self>) -> Option<SmallVec<[ast::Stmt; 1]>> { - make_stmts_default!(self) - } - - fn make_ty(self: Box<Self>) -> Option<P<ast::Ty>> { - None - } - - fn make_arms(self: Box<Self>) -> Option<SmallVec<[ast::Arm; 1]>> { - None - } - - fn make_fields(self: Box<Self>) -> Option<SmallVec<[ast::Field; 1]>> { - None - } - - fn make_field_patterns(self: Box<Self>) -> Option<SmallVec<[ast::FieldPat; 1]>> { - None - } - - fn make_generic_params(self: Box<Self>) -> Option<SmallVec<[ast::GenericParam; 1]>> { - None - } - - fn make_params(self: Box<Self>) -> Option<SmallVec<[ast::Param; 1]>> { - None - } - - fn make_struct_fields(self: Box<Self>) -> Option<SmallVec<[ast::StructField; 1]>> { - None - } - - fn make_variants(self: Box<Self>) -> Option<SmallVec<[ast::Variant; 1]>> { - None - } -} - -macro_rules! make_MacEager { - ( $( $fld:ident: $t:ty, )* ) => { - /// `MacResult` implementation for the common case where you've already - /// built each form of AST that you might return. - #[derive(Default)] - pub struct MacEager { - $( - pub $fld: Option<$t>, - )* - } - - impl MacEager { - $( - pub fn $fld(v: $t) -> Box<dyn MacResult> { - Box::new(MacEager { - $fld: Some(v), - ..Default::default() - }) - } - )* - } - } -} - -make_MacEager! { - expr: P<ast::Expr>, - pat: P<ast::Pat>, - items: SmallVec<[P<ast::Item>; 1]>, - impl_items: SmallVec<[ast::ImplItem; 1]>, - trait_items: SmallVec<[ast::TraitItem; 1]>, - foreign_items: SmallVec<[ast::ForeignItem; 1]>, - stmts: SmallVec<[ast::Stmt; 1]>, - ty: P<ast::Ty>, -} - -impl MacResult for MacEager { - fn make_expr(self: Box<Self>) -> Option<P<ast::Expr>> { - self.expr - } - - fn make_items(self: Box<Self>) -> Option<SmallVec<[P<ast::Item>; 1]>> { - self.items - } - - fn make_impl_items(self: Box<Self>) -> Option<SmallVec<[ast::ImplItem; 1]>> { - self.impl_items - } - - fn make_trait_items(self: Box<Self>) -> Option<SmallVec<[ast::TraitItem; 1]>> { - self.trait_items - } - - fn make_foreign_items(self: Box<Self>) -> Option<SmallVec<[ast::ForeignItem; 1]>> { - self.foreign_items - } - - fn make_stmts(self: Box<Self>) -> Option<SmallVec<[ast::Stmt; 1]>> { - match self.stmts.as_ref().map_or(0, |s| s.len()) { - 0 => make_stmts_default!(self), - _ => self.stmts, - } - } - - fn make_pat(self: Box<Self>) -> Option<P<ast::Pat>> { - if let Some(p) = self.pat { - return Some(p); - } - if let Some(e) = self.expr { - if let ast::ExprKind::Lit(_) = e.kind { - return Some(P(ast::Pat { - id: ast::DUMMY_NODE_ID, - span: e.span, - kind: PatKind::Lit(e), - })); - } - } - None - } - - fn make_ty(self: Box<Self>) -> Option<P<ast::Ty>> { - self.ty - } -} - -/// Fill-in macro expansion result, to allow compilation to continue -/// after hitting errors. -#[derive(Copy, Clone)] -pub struct DummyResult { - is_error: bool, - span: Span, -} - -impl DummyResult { - /// Creates a default MacResult that can be anything. - /// - /// Use this as a return value after hitting any errors and - /// calling `span_err`. - pub fn any(span: Span) -> Box<dyn MacResult+'static> { - Box::new(DummyResult { is_error: true, span }) - } - - /// Same as `any`, but must be a valid fragment, not error. - pub fn any_valid(span: Span) -> Box<dyn MacResult+'static> { - Box::new(DummyResult { is_error: false, span }) - } - - /// A plain dummy expression. - pub fn raw_expr(sp: Span, is_error: bool) -> P<ast::Expr> { - P(ast::Expr { - id: ast::DUMMY_NODE_ID, - kind: if is_error { ast::ExprKind::Err } else { ast::ExprKind::Tup(Vec::new()) }, - span: sp, - attrs: ThinVec::new(), - }) - } - - /// A plain dummy pattern. - pub fn raw_pat(sp: Span) -> ast::Pat { - ast::Pat { - id: ast::DUMMY_NODE_ID, - kind: PatKind::Wild, - span: sp, - } - } - - /// A plain dummy type. - pub fn raw_ty(sp: Span, is_error: bool) -> P<ast::Ty> { - P(ast::Ty { - id: ast::DUMMY_NODE_ID, - kind: if is_error { ast::TyKind::Err } else { ast::TyKind::Tup(Vec::new()) }, - span: sp - }) - } -} - -impl MacResult for DummyResult { - fn make_expr(self: Box<DummyResult>) -> Option<P<ast::Expr>> { - Some(DummyResult::raw_expr(self.span, self.is_error)) - } - - fn make_pat(self: Box<DummyResult>) -> Option<P<ast::Pat>> { - Some(P(DummyResult::raw_pat(self.span))) - } - - fn make_items(self: Box<DummyResult>) -> Option<SmallVec<[P<ast::Item>; 1]>> { - Some(SmallVec::new()) - } - - fn make_impl_items(self: Box<DummyResult>) -> Option<SmallVec<[ast::ImplItem; 1]>> { - Some(SmallVec::new()) - } - - fn make_trait_items(self: Box<DummyResult>) -> Option<SmallVec<[ast::TraitItem; 1]>> { - Some(SmallVec::new()) - } - - fn make_foreign_items(self: Box<Self>) -> Option<SmallVec<[ast::ForeignItem; 1]>> { - Some(SmallVec::new()) - } - - fn make_stmts(self: Box<DummyResult>) -> Option<SmallVec<[ast::Stmt; 1]>> { - Some(smallvec![ast::Stmt { - id: ast::DUMMY_NODE_ID, - kind: ast::StmtKind::Expr(DummyResult::raw_expr(self.span, self.is_error)), - span: self.span, - }]) - } - - fn make_ty(self: Box<DummyResult>) -> Option<P<ast::Ty>> { - Some(DummyResult::raw_ty(self.span, self.is_error)) - } - - fn make_arms(self: Box<DummyResult>) -> Option<SmallVec<[ast::Arm; 1]>> { - Some(SmallVec::new()) - } - - fn make_fields(self: Box<DummyResult>) -> Option<SmallVec<[ast::Field; 1]>> { - Some(SmallVec::new()) - } - - fn make_field_patterns(self: Box<DummyResult>) -> Option<SmallVec<[ast::FieldPat; 1]>> { - Some(SmallVec::new()) - } - - fn make_generic_params(self: Box<DummyResult>) -> Option<SmallVec<[ast::GenericParam; 1]>> { - Some(SmallVec::new()) - } - - fn make_params(self: Box<DummyResult>) -> Option<SmallVec<[ast::Param; 1]>> { - Some(SmallVec::new()) - } - - fn make_struct_fields(self: Box<DummyResult>) -> Option<SmallVec<[ast::StructField; 1]>> { - Some(SmallVec::new()) - } - - fn make_variants(self: Box<DummyResult>) -> Option<SmallVec<[ast::Variant; 1]>> { - Some(SmallVec::new()) - } -} - -/// A syntax extension kind. -pub enum SyntaxExtensionKind { - /// A token-based function-like macro. - Bang( - /// An expander with signature TokenStream -> TokenStream. - Box<dyn ProcMacro + sync::Sync + sync::Send>, - ), - - /// An AST-based function-like macro. - LegacyBang( - /// An expander with signature TokenStream -> AST. - Box<dyn TTMacroExpander + sync::Sync + sync::Send>, - ), - - /// A token-based attribute macro. - Attr( - /// An expander with signature (TokenStream, TokenStream) -> TokenStream. - /// The first TokenSteam is the attribute itself, the second is the annotated item. - /// The produced TokenSteam replaces the input TokenSteam. - Box<dyn AttrProcMacro + sync::Sync + sync::Send>, - ), - - /// An AST-based attribute macro. - LegacyAttr( - /// An expander with signature (AST, AST) -> AST. - /// The first AST fragment is the attribute itself, the second is the annotated item. - /// The produced AST fragment replaces the input AST fragment. - Box<dyn MultiItemModifier + sync::Sync + sync::Send>, - ), - - /// A trivial attribute "macro" that does nothing, - /// only keeps the attribute and marks it as inert, - /// thus making it ineligible for further expansion. - NonMacroAttr { - /// Suppresses the `unused_attributes` lint for this attribute. - mark_used: bool, - }, - - /// A token-based derive macro. - Derive( - /// An expander with signature TokenStream -> TokenStream (not yet). - /// The produced TokenSteam is appended to the input TokenSteam. - Box<dyn MultiItemModifier + sync::Sync + sync::Send>, - ), - - /// An AST-based derive macro. - LegacyDerive( - /// An expander with signature AST -> AST. - /// The produced AST fragment is appended to the input AST fragment. - Box<dyn MultiItemModifier + sync::Sync + sync::Send>, - ), -} - -/// A struct representing a macro definition in "lowered" form ready for expansion. -pub struct SyntaxExtension { - /// A syntax extension kind. - pub kind: SyntaxExtensionKind, - /// Span of the macro definition. - pub span: Span, - /// Whitelist of unstable features that are treated as stable inside this macro. - pub allow_internal_unstable: Option<Lrc<[Symbol]>>, - /// Suppresses the `unsafe_code` lint for code produced by this macro. - pub allow_internal_unsafe: bool, - /// Enables the macro helper hack (`ident!(...)` -> `$crate::ident!(...)`) for this macro. - pub local_inner_macros: bool, - /// The macro's stability info. - pub stability: Option<Stability>, - /// The macro's deprecation info. - pub deprecation: Option<Deprecation>, - /// Names of helper attributes registered by this macro. - pub helper_attrs: Vec<Symbol>, - /// Edition of the crate in which this macro is defined. - pub edition: Edition, - /// Built-in macros have a couple of special properties like availability - /// in `#[no_implicit_prelude]` modules, so we have to keep this flag. - pub is_builtin: bool, - /// We have to identify macros providing a `Copy` impl early for compatibility reasons. - pub is_derive_copy: bool, -} - -impl SyntaxExtension { - /// Returns which kind of macro calls this syntax extension. - pub fn macro_kind(&self) -> MacroKind { - match self.kind { - SyntaxExtensionKind::Bang(..) | - SyntaxExtensionKind::LegacyBang(..) => MacroKind::Bang, - SyntaxExtensionKind::Attr(..) | - SyntaxExtensionKind::LegacyAttr(..) | - SyntaxExtensionKind::NonMacroAttr { .. } => MacroKind::Attr, - SyntaxExtensionKind::Derive(..) | - SyntaxExtensionKind::LegacyDerive(..) => MacroKind::Derive, - } - } - - /// Constructs a syntax extension with default properties. - pub fn default(kind: SyntaxExtensionKind, edition: Edition) -> SyntaxExtension { - SyntaxExtension { - span: DUMMY_SP, - allow_internal_unstable: None, - allow_internal_unsafe: false, - local_inner_macros: false, - stability: None, - deprecation: None, - helper_attrs: Vec::new(), - edition, - is_builtin: false, - is_derive_copy: false, - kind, - } - } - - /// Constructs a syntax extension with the given properties - /// and other properties converted from attributes. - pub fn new( - sess: &ParseSess, - kind: SyntaxExtensionKind, - span: Span, - helper_attrs: Vec<Symbol>, - edition: Edition, - name: Name, - attrs: &[ast::Attribute], - ) -> SyntaxExtension { - let allow_internal_unstable = attr::allow_internal_unstable( - &attrs, &sess.span_diagnostic, - ).map(|features| features.collect::<Vec<Symbol>>().into()); - - let mut local_inner_macros = false; - if let Some(macro_export) = attr::find_by_name(attrs, sym::macro_export) { - if let Some(l) = macro_export.meta_item_list() { - local_inner_macros = attr::list_contains_name(&l, sym::local_inner_macros); - } - } - - let is_builtin = attr::contains_name(attrs, sym::rustc_builtin_macro); - - SyntaxExtension { - kind, - span, - allow_internal_unstable, - allow_internal_unsafe: attr::contains_name(attrs, sym::allow_internal_unsafe), - local_inner_macros, - stability: attr::find_stability(&sess, attrs, span), - deprecation: attr::find_deprecation(&sess, attrs, span), - helper_attrs, - edition, - is_builtin, - is_derive_copy: is_builtin && name == sym::Copy, - } - } - - pub fn dummy_bang(edition: Edition) -> SyntaxExtension { - fn expander<'cx>(_: &'cx mut ExtCtxt<'_>, span: Span, _: TokenStream) - -> Box<dyn MacResult + 'cx> { - DummyResult::any(span) - } - SyntaxExtension::default(SyntaxExtensionKind::LegacyBang(Box::new(expander)), edition) - } - - pub fn dummy_derive(edition: Edition) -> SyntaxExtension { - fn expander(_: &mut ExtCtxt<'_>, _: Span, _: &ast::MetaItem, _: Annotatable) - -> Vec<Annotatable> { - Vec::new() - } - SyntaxExtension::default(SyntaxExtensionKind::Derive(Box::new(expander)), edition) - } - - pub fn non_macro_attr(mark_used: bool, edition: Edition) -> SyntaxExtension { - SyntaxExtension::default(SyntaxExtensionKind::NonMacroAttr { mark_used }, edition) - } - - pub fn expn_data(&self, parent: ExpnId, call_site: Span, descr: Symbol) -> ExpnData { - ExpnData { - kind: ExpnKind::Macro(self.macro_kind(), descr), - parent, - call_site, - def_site: self.span, - allow_internal_unstable: self.allow_internal_unstable.clone(), - allow_internal_unsafe: self.allow_internal_unsafe, - local_inner_macros: self.local_inner_macros, - edition: self.edition, - } - } -} - -pub type NamedSyntaxExtension = (Name, SyntaxExtension); - -/// Result of resolving a macro invocation. -pub enum InvocationRes { - Single(Lrc<SyntaxExtension>), - DeriveContainer(Vec<Lrc<SyntaxExtension>>), -} - -/// Error type that denotes indeterminacy. -pub struct Indeterminate; - -bitflags::bitflags! { - /// Built-in derives that need some extra tracking beyond the usual macro functionality. - #[derive(Default)] - pub struct SpecialDerives: u8 { - const PARTIAL_EQ = 1 << 0; - const EQ = 1 << 1; - const COPY = 1 << 2; - } -} - -pub trait Resolver { - fn next_node_id(&mut self) -> NodeId; - - fn resolve_dollar_crates(&mut self); - fn visit_ast_fragment_with_placeholders(&mut self, expn_id: ExpnId, fragment: &AstFragment, - extra_placeholders: &[NodeId]); - fn register_builtin_macro(&mut self, ident: ast::Ident, ext: SyntaxExtension); - - fn expansion_for_ast_pass( - &mut self, - call_site: Span, - pass: AstPass, - features: &[Symbol], - parent_module_id: Option<NodeId>, - ) -> ExpnId; - - fn resolve_imports(&mut self); - - fn resolve_macro_invocation( - &mut self, invoc: &Invocation, eager_expansion_root: ExpnId, force: bool - ) -> Result<InvocationRes, Indeterminate>; - - fn check_unused_macros(&self); - - fn has_derives(&self, expn_id: ExpnId, derives: SpecialDerives) -> bool; - fn add_derives(&mut self, expn_id: ExpnId, derives: SpecialDerives); -} - -#[derive(Clone)] -pub struct ModuleData { - pub mod_path: Vec<ast::Ident>, - pub directory: PathBuf, -} - -#[derive(Clone)] -pub struct ExpansionData { - pub id: ExpnId, - pub depth: usize, - pub module: Rc<ModuleData>, - pub directory_ownership: DirectoryOwnership, - pub prior_type_ascription: Option<(Span, bool)>, -} - -/// One of these is made during expansion and incrementally updated as we go; -/// 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 ecfg: expand::ExpansionConfig<'a>, - pub root_path: PathBuf, - pub resolver: &'a mut dyn Resolver, - pub current_expansion: ExpansionData, - pub expansions: FxHashMap<Span, Vec<String>>, -} - -impl<'a> ExtCtxt<'a> { - pub fn new(parse_sess: &'a parse::ParseSess, - ecfg: expand::ExpansionConfig<'a>, - resolver: &'a mut dyn Resolver) - -> ExtCtxt<'a> { - ExtCtxt { - parse_sess, - ecfg, - root_path: PathBuf::new(), - resolver, - current_expansion: ExpansionData { - id: ExpnId::root(), - depth: 0, - module: Rc::new(ModuleData { mod_path: Vec::new(), directory: PathBuf::new() }), - directory_ownership: DirectoryOwnership::Owned { relative: None }, - prior_type_ascription: None, - }, - expansions: FxHashMap::default(), - } - } - - /// Returns a `Folder` for deeply expanding all macros in an AST node. - pub fn expander<'b>(&'b mut self) -> expand::MacroExpander<'b, 'a> { - expand::MacroExpander::new(self, false) - } - - /// Returns a `Folder` that deeply expands all macros and assigns all `NodeId`s in an AST node. - /// Once `NodeId`s are assigned, the node may not be expanded, removed, or otherwise modified. - pub fn monotonic_expander<'b>(&'b mut self) -> expand::MacroExpander<'b, 'a> { - expand::MacroExpander::new(self, true) - } - pub fn new_parser_from_tts(&self, stream: TokenStream) -> parser::Parser<'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 cfg(&self) -> &ast::CrateConfig { &self.parse_sess.config } - pub fn call_site(&self) -> Span { - self.current_expansion.id.expn_data().call_site - } - - /// Equivalent of `Span::def_site` from the proc macro API, - /// except that the location is taken from the span passed as an argument. - pub fn with_def_site_ctxt(&self, span: Span) -> Span { - span.with_def_site_ctxt(self.current_expansion.id) - } - - /// Equivalent of `Span::call_site` from the proc macro API, - /// except that the location is taken from the span passed as an argument. - pub fn with_call_site_ctxt(&self, span: Span) -> Span { - span.with_call_site_ctxt(self.current_expansion.id) - } - - /// Equivalent of `Span::mixed_site` from the proc macro API, - /// except that the location is taken from the span passed as an argument. - pub fn with_mixed_site_ctxt(&self, span: Span) -> Span { - span.with_mixed_site_ctxt(self.current_expansion.id) - } - - /// Returns span for the macro which originally caused the current expansion to happen. - /// - /// Stops backtracing at include! boundary. - pub fn expansion_cause(&self) -> Option<Span> { - let mut expn_id = self.current_expansion.id; - let mut last_macro = None; - loop { - let expn_data = expn_id.expn_data(); - // Stop going up the backtrace once include! is encountered - if expn_data.is_root() || expn_data.kind.descr() == sym::include { - break; - } - expn_id = expn_data.call_site.ctxt().outer_expn(); - last_macro = Some(expn_data.call_site); - } - last_macro - } - - pub fn struct_span_warn<S: Into<MultiSpan>>(&self, - sp: S, - msg: &str) - -> DiagnosticBuilder<'a> { - self.parse_sess.span_diagnostic.struct_span_warn(sp, msg) - } - pub fn struct_span_err<S: Into<MultiSpan>>(&self, - sp: S, - msg: &str) - -> DiagnosticBuilder<'a> { - self.parse_sess.span_diagnostic.struct_span_err(sp, msg) - } - pub fn struct_span_fatal<S: Into<MultiSpan>>(&self, - sp: S, - msg: &str) - -> DiagnosticBuilder<'a> { - self.parse_sess.span_diagnostic.struct_span_fatal(sp, msg) - } - - /// Emit `msg` attached to `sp`, and stop compilation immediately. - /// - /// `span_err` should be strongly preferred where-ever possible: - /// this should *only* be used when: - /// - /// - continuing has a high risk of flow-on errors (e.g., errors in - /// declaring a macro would cause all uses of that macro to - /// complain about "undefined macro"), or - /// - there is literally nothing else that can be done (however, - /// in most cases one can construct a dummy expression/item to - /// substitute; we never hit resolve/type-checking so the dummy - /// value doesn't have to match anything) - pub fn span_fatal<S: Into<MultiSpan>>(&self, sp: S, msg: &str) -> ! { - self.parse_sess.span_diagnostic.span_fatal(sp, msg).raise(); - } - - /// Emit `msg` attached to `sp`, without immediately stopping - /// compilation. - /// - /// Compilation will be stopped in the near future (at the end of - /// the macro expansion phase). - pub fn span_err<S: Into<MultiSpan>>(&self, sp: S, msg: &str) { - self.parse_sess.span_diagnostic.span_err(sp, msg); - } - pub fn span_err_with_code<S: Into<MultiSpan>>(&self, sp: S, msg: &str, code: DiagnosticId) { - self.parse_sess.span_diagnostic.span_err_with_code(sp, msg, code); - } - pub fn span_warn<S: Into<MultiSpan>>(&self, sp: S, msg: &str) { - self.parse_sess.span_diagnostic.span_warn(sp, msg); - } - pub fn span_bug<S: Into<MultiSpan>>(&self, sp: S, msg: &str) -> ! { - self.parse_sess.span_diagnostic.span_bug(sp, msg); - } - pub fn trace_macros_diag(&mut self) { - for (sp, notes) in self.expansions.iter() { - let mut db = self.parse_sess.span_diagnostic.span_note_diag(*sp, "trace_macro"); - for note in notes { - db.note(note); - } - db.emit(); - } - // Fixme: does this result in errors? - self.expansions.clear(); - } - pub fn bug(&self, msg: &str) -> ! { - self.parse_sess.span_diagnostic.bug(msg); - } - pub fn trace_macros(&self) -> bool { - self.ecfg.trace_mac - } - pub fn set_trace_macros(&mut self, x: bool) { - self.ecfg.trace_mac = x - } - pub fn ident_of(&self, st: &str, sp: Span) -> ast::Ident { - ast::Ident::from_str_and_span(st, sp) - } - pub fn std_path(&self, components: &[Symbol]) -> Vec<ast::Ident> { - let def_site = self.with_def_site_ctxt(DUMMY_SP); - iter::once(Ident::new(kw::DollarCrate, def_site)) - .chain(components.iter().map(|&s| Ident::with_dummy_span(s))) - .collect() - } - pub fn name_of(&self, st: &str) -> ast::Name { - Symbol::intern(st) - } - - pub fn check_unused_macros(&self) { - self.resolver.check_unused_macros(); - } - - /// Resolves a path mentioned inside Rust code. - /// - /// This unifies the logic used for resolving `include_X!`, and `#[doc(include)]` file paths. - /// - /// Returns an absolute path to the file that `path` refers to. - pub fn resolve_path(&self, path: impl Into<PathBuf>, span: Span) -> PathBuf { - let path = path.into(); - - // Relative paths are resolved relative to the file in which they are found - // after macro expansion (that is, they are unhygienic). - if !path.is_absolute() { - let callsite = span.source_callsite(); - let mut result = match self.source_map().span_to_unmapped_path(callsite) { - FileName::Real(path) => path, - FileName::DocTest(path, _) => path, - other => panic!("cannot resolve relative path in non-file source `{}`", other), - }; - result.pop(); - result.push(path); - result - } else { - path - } - } -} - -/// Extracts a string literal from the macro expanded version of `expr`, -/// emitting `err_msg` if `expr` is not a string literal. This does not stop -/// compilation on error, merely emits a non-fatal error and returns `None`. -pub fn expr_to_spanned_string<'a>( - cx: &'a mut ExtCtxt<'_>, - expr: P<ast::Expr>, - err_msg: &str, -) -> Result<(Symbol, ast::StrStyle, Span), Option<DiagnosticBuilder<'a>>> { - // Perform eager expansion on the expression. - // We want to be able to handle e.g., `concat!("foo", "bar")`. - let expr = cx.expander().fully_expand_fragment(AstFragment::Expr(expr)).make_expr(); - - Err(match expr.kind { - ast::ExprKind::Lit(ref l) => match l.kind { - ast::LitKind::Str(s, style) => return Ok((s, style, expr.span)), - ast::LitKind::Err(_) => None, - _ => Some(cx.struct_span_err(l.span, err_msg)) - }, - ast::ExprKind::Err => None, - _ => Some(cx.struct_span_err(expr.span, err_msg)) - }) -} - -pub fn expr_to_string(cx: &mut ExtCtxt<'_>, expr: P<ast::Expr>, err_msg: &str) - -> Option<(Symbol, ast::StrStyle)> { - expr_to_spanned_string(cx, expr, err_msg) - .map_err(|err| err.map(|mut err| err.emit())) - .ok() - .map(|(symbol, style, _)| (symbol, style)) -} - -/// Non-fatally assert that `tts` is empty. Note that this function -/// returns even when `tts` is non-empty, macros that *need* to stop -/// compilation should call -/// `cx.parse_sess.span_diagnostic.abort_if_errors()` (this should be -/// done as rarely as possible). -pub fn check_zero_tts(cx: &ExtCtxt<'_>, - sp: Span, - tts: TokenStream, - name: &str) { - if !tts.is_empty() { - cx.span_err(sp, &format!("{} takes no arguments", name)); - } -} - -/// Interpreting `tts` as a comma-separated sequence of expressions, -/// expect exactly one string literal, or emit an error and return `None`. -pub fn get_single_str_from_tts(cx: &mut ExtCtxt<'_>, - sp: Span, - tts: TokenStream, - name: &str) - -> Option<String> { - let mut p = cx.new_parser_from_tts(tts); - if p.token == token::Eof { - cx.span_err(sp, &format!("{} takes 1 argument", name)); - return None - } - let ret = panictry!(p.parse_expr()); - let _ = p.eat(&token::Comma); - - if p.token != token::Eof { - cx.span_err(sp, &format!("{} takes 1 argument", name)); - } - expr_to_string(cx, ret, "argument must be a string literal").map(|(s, _)| { - s.to_string() - }) -} - -/// Extracts comma-separated expressions from `tts`. If there is a -/// parsing error, emit a non-fatal error and return `None`. -pub fn get_exprs_from_tts(cx: &mut ExtCtxt<'_>, - sp: Span, - tts: TokenStream) -> Option<Vec<P<ast::Expr>>> { - let mut p = cx.new_parser_from_tts(tts); - let mut es = Vec::new(); - while p.token != token::Eof { - let expr = panictry!(p.parse_expr()); - - // Perform eager expansion on the expression. - // We want to be able to handle e.g., `concat!("foo", "bar")`. - let expr = cx.expander().fully_expand_fragment(AstFragment::Expr(expr)).make_expr(); - - es.push(expr); - if p.eat(&token::Comma) { - continue; - } - if p.token != token::Eof { - cx.span_err(sp, "expected token: `,`"); - return None; - } - } - Some(es) -} |