| use crate::ast::{self, Block, Ident, LitKind, NodeId, PatKind, Path}; |
| use crate::ast::{MacStmtStyle, StmtKind, ItemKind}; |
| use crate::attr::{self, HasAttrs}; |
| use crate::source_map::{dummy_spanned, respan}; |
| use crate::config::StripUnconfigured; |
| use crate::ext::base::*; |
| use crate::ext::derive::{add_derived_markers, collect_derives}; |
| use crate::ext::hygiene::{Mark, SyntaxContext}; |
| 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::token; |
| use crate::parse::parser::Parser; |
| use crate::ptr::P; |
| use crate::symbol::Symbol; |
| use crate::symbol::{kw, sym}; |
| use crate::tokenstream::{TokenStream, TokenTree}; |
| use crate::visit::{self, Visitor}; |
| use crate::util::map_in_place::MapInPlace; |
| |
| use errors::{Applicability, FatalError}; |
| use smallvec::{smallvec, SmallVec}; |
| use syntax_pos::{Span, DUMMY_SP, FileName}; |
| |
| use rustc_data_structures::fx::FxHashMap; |
| use rustc_data_structures::sync::Lrc; |
| use std::fs; |
| use std::io::ErrorKind; |
| use std::{iter, mem}; |
| use std::ops::DerefMut; |
| use std::rc::Rc; |
| use std::path::PathBuf; |
| |
| macro_rules! ast_fragments { |
| ( |
| $($Kind:ident($AstTy:ty) { |
| $kind_name:expr; |
| $(one fn $mut_visit_ast:ident; fn $visit_ast:ident;)? |
| $(many fn $flat_map_ast_elt:ident; fn $visit_ast_elt:ident;)? |
| fn $make_ast:ident; |
| })* |
| ) => { |
| /// A fragment of AST that can be produced by a single macro expansion. |
| /// Can also serve as an input and intermediate result for macro expansion operations. |
| pub enum AstFragment { |
| OptExpr(Option<P<ast::Expr>>), |
| $($Kind($AstTy),)* |
| } |
| |
| /// "Discriminant" of an AST fragment. |
| #[derive(Copy, Clone, PartialEq, Eq)] |
| pub enum AstFragmentKind { |
| OptExpr, |
| $($Kind,)* |
| } |
| |
| impl AstFragmentKind { |
| pub fn name(self) -> &'static str { |
| match self { |
| AstFragmentKind::OptExpr => "expression", |
| $(AstFragmentKind::$Kind => $kind_name,)* |
| } |
| } |
| |
| fn make_from<'a>(self, result: Box<dyn MacResult + 'a>) -> Option<AstFragment> { |
| match self { |
| AstFragmentKind::OptExpr => |
| result.make_expr().map(Some).map(AstFragment::OptExpr), |
| $(AstFragmentKind::$Kind => result.$make_ast().map(AstFragment::$Kind),)* |
| } |
| } |
| } |
| |
| impl AstFragment { |
| pub fn make_opt_expr(self) -> Option<P<ast::Expr>> { |
| match self { |
| AstFragment::OptExpr(expr) => expr, |
| _ => panic!("AstFragment::make_* called on the wrong kind of fragment"), |
| } |
| } |
| |
| $(pub fn $make_ast(self) -> $AstTy { |
| match self { |
| AstFragment::$Kind(ast) => ast, |
| _ => panic!("AstFragment::make_* called on the wrong kind of fragment"), |
| } |
| })* |
| |
| pub fn mut_visit_with<F: MutVisitor>(&mut self, vis: &mut F) { |
| match self { |
| AstFragment::OptExpr(opt_expr) => { |
| visit_clobber(opt_expr, |opt_expr| { |
| if let Some(expr) = opt_expr { |
| vis.filter_map_expr(expr) |
| } else { |
| None |
| } |
| }); |
| } |
| $($(AstFragment::$Kind(ast) => vis.$mut_visit_ast(ast),)?)* |
| $($(AstFragment::$Kind(ast) => |
| ast.flat_map_in_place(|ast| vis.$flat_map_ast_elt(ast)),)?)* |
| } |
| } |
| |
| pub fn visit_with<'a, V: Visitor<'a>>(&'a self, visitor: &mut V) { |
| match *self { |
| AstFragment::OptExpr(Some(ref expr)) => visitor.visit_expr(expr), |
| AstFragment::OptExpr(None) => {} |
| $($(AstFragment::$Kind(ref ast) => visitor.$visit_ast(ast),)?)* |
| $($(AstFragment::$Kind(ref ast) => for ast_elt in &ast[..] { |
| visitor.$visit_ast_elt(ast_elt); |
| })?)* |
| } |
| } |
| } |
| |
| impl<'a, 'b> MutVisitor for MacroExpander<'a, 'b> { |
| fn filter_map_expr(&mut self, expr: P<ast::Expr>) -> Option<P<ast::Expr>> { |
| self.expand_fragment(AstFragment::OptExpr(Some(expr))).make_opt_expr() |
| } |
| $($(fn $mut_visit_ast(&mut self, ast: &mut $AstTy) { |
| visit_clobber(ast, |ast| self.expand_fragment(AstFragment::$Kind(ast)).$make_ast()); |
| })?)* |
| $($(fn $flat_map_ast_elt(&mut self, ast_elt: <$AstTy as IntoIterator>::Item) -> $AstTy { |
| self.expand_fragment(AstFragment::$Kind(smallvec![ast_elt])).$make_ast() |
| })?)* |
| } |
| |
| impl<'a> MacResult for crate::ext::tt::macro_rules::ParserAnyMacro<'a> { |
| $(fn $make_ast(self: Box<crate::ext::tt::macro_rules::ParserAnyMacro<'a>>) |
| -> Option<$AstTy> { |
| Some(self.make(AstFragmentKind::$Kind).$make_ast()) |
| })* |
| } |
| } |
| } |
| |
| ast_fragments! { |
| Expr(P<ast::Expr>) { "expression"; one fn visit_expr; fn visit_expr; fn make_expr; } |
| Pat(P<ast::Pat>) { "pattern"; one fn visit_pat; fn visit_pat; fn make_pat; } |
| Ty(P<ast::Ty>) { "type"; one fn visit_ty; fn visit_ty; fn make_ty; } |
| Stmts(SmallVec<[ast::Stmt; 1]>) { |
| "statement"; many fn flat_map_stmt; fn visit_stmt; fn make_stmts; |
| } |
| Items(SmallVec<[P<ast::Item>; 1]>) { |
| "item"; many fn flat_map_item; fn visit_item; fn make_items; |
| } |
| TraitItems(SmallVec<[ast::TraitItem; 1]>) { |
| "trait item"; many fn flat_map_trait_item; fn visit_trait_item; fn make_trait_items; |
| } |
| ImplItems(SmallVec<[ast::ImplItem; 1]>) { |
| "impl item"; many fn flat_map_impl_item; fn visit_impl_item; fn make_impl_items; |
| } |
| ForeignItems(SmallVec<[ast::ForeignItem; 1]>) { |
| "foreign item"; many fn flat_map_foreign_item; fn visit_foreign_item; fn make_foreign_items; |
| } |
| } |
| |
| impl AstFragmentKind { |
| fn dummy(self, span: Span) -> Option<AstFragment> { |
| self.make_from(DummyResult::any(span)) |
| } |
| |
| fn expect_from_annotatables<I: IntoIterator<Item = Annotatable>>(self, items: I) |
| -> AstFragment { |
| let mut items = items.into_iter(); |
| match self { |
| AstFragmentKind::Items => |
| AstFragment::Items(items.map(Annotatable::expect_item).collect()), |
| AstFragmentKind::ImplItems => |
| AstFragment::ImplItems(items.map(Annotatable::expect_impl_item).collect()), |
| AstFragmentKind::TraitItems => |
| AstFragment::TraitItems(items.map(Annotatable::expect_trait_item).collect()), |
| AstFragmentKind::ForeignItems => |
| AstFragment::ForeignItems(items.map(Annotatable::expect_foreign_item).collect()), |
| AstFragmentKind::Stmts => |
| AstFragment::Stmts(items.map(Annotatable::expect_stmt).collect()), |
| AstFragmentKind::Expr => AstFragment::Expr( |
| items.next().expect("expected exactly one expression").expect_expr() |
| ), |
| AstFragmentKind::OptExpr => |
| AstFragment::OptExpr(items.next().map(Annotatable::expect_expr)), |
| AstFragmentKind::Pat | AstFragmentKind::Ty => |
| panic!("patterns and types aren't annotatable"), |
| } |
| } |
| } |
| |
| pub struct Invocation { |
| pub kind: InvocationKind, |
| fragment_kind: AstFragmentKind, |
| pub expansion_data: ExpansionData, |
| } |
| |
| pub enum InvocationKind { |
| Bang { |
| mac: ast::Mac, |
| ident: Option<Ident>, |
| span: Span, |
| }, |
| Attr { |
| attr: Option<ast::Attribute>, |
| traits: Vec<Path>, |
| item: Annotatable, |
| // We temporarily report errors for attribute macros placed after derives |
| after_derive: bool, |
| }, |
| Derive { |
| path: Path, |
| item: Annotatable, |
| }, |
| } |
| |
| impl Invocation { |
| pub fn span(&self) -> Span { |
| match self.kind { |
| InvocationKind::Bang { span, .. } => span, |
| InvocationKind::Attr { attr: Some(ref attr), .. } => attr.span, |
| InvocationKind::Attr { attr: None, .. } => DUMMY_SP, |
| InvocationKind::Derive { ref path, .. } => path.span, |
| } |
| } |
| } |
| |
| pub struct MacroExpander<'a, 'b> { |
| pub cx: &'a mut ExtCtxt<'b>, |
| monotonic: bool, // cf. `cx.monotonic_expander()` |
| } |
| |
| impl<'a, 'b> MacroExpander<'a, 'b> { |
| pub fn new(cx: &'a mut ExtCtxt<'b>, monotonic: bool) -> Self { |
| MacroExpander { cx, monotonic } |
| } |
| |
| pub fn expand_crate(&mut self, mut krate: ast::Crate) -> ast::Crate { |
| let mut module = ModuleData { |
| mod_path: vec![Ident::from_str(&self.cx.ecfg.crate_name)], |
| directory: match self.cx.source_map().span_to_unmapped_path(krate.span) { |
| FileName::Real(path) => path, |
| other => PathBuf::from(other.to_string()), |
| }, |
| }; |
| module.directory.pop(); |
| self.cx.root_path = module.directory.clone(); |
| self.cx.current_expansion.module = Rc::new(module); |
| self.cx.current_expansion.crate_span = Some(krate.span); |
| |
| let orig_mod_span = krate.module.inner; |
| |
| let krate_item = AstFragment::Items(smallvec![P(ast::Item { |
| attrs: krate.attrs, |
| span: krate.span, |
| node: ast::ItemKind::Mod(krate.module), |
| ident: Ident::invalid(), |
| id: ast::DUMMY_NODE_ID, |
| vis: respan(krate.span.shrink_to_lo(), ast::VisibilityKind::Public), |
| tokens: None, |
| })]); |
| |
| match self.expand_fragment(krate_item).make_items().pop().map(P::into_inner) { |
| Some(ast::Item { attrs, node: ast::ItemKind::Mod(module), .. }) => { |
| krate.attrs = attrs; |
| krate.module = module; |
| }, |
| None => { |
| // Resolution failed so we return an empty expansion |
| krate.attrs = vec![]; |
| krate.module = ast::Mod { |
| inner: orig_mod_span, |
| items: vec![], |
| inline: true, |
| }; |
| }, |
| _ => unreachable!(), |
| }; |
| self.cx.trace_macros_diag(); |
| krate |
| } |
| |
| // Fully expand all macro invocations in this AST fragment. |
| fn expand_fragment(&mut self, input_fragment: AstFragment) -> AstFragment { |
| let orig_expansion_data = self.cx.current_expansion.clone(); |
| self.cx.current_expansion.depth = 0; |
| |
| // Collect all macro invocations and replace them with placeholders. |
| let (mut fragment_with_placeholders, mut invocations) |
| = self.collect_invocations(input_fragment, &[]); |
| |
| // Optimization: if we resolve all imports now, |
| // we'll be able to immediately resolve most of imported macros. |
| self.resolve_imports(); |
| |
| // Resolve paths in all invocations and produce output expanded fragments for them, but |
| // do not insert them into our input AST fragment yet, only store in `expanded_fragments`. |
| // The output fragments also go through expansion recursively until no invocations are left. |
| // Unresolved macros produce dummy outputs as a recovery measure. |
| invocations.reverse(); |
| let mut expanded_fragments = Vec::new(); |
| let mut derives: FxHashMap<Mark, Vec<_>> = FxHashMap::default(); |
| let mut undetermined_invocations = Vec::new(); |
| let (mut progress, mut force) = (false, !self.monotonic); |
| loop { |
| let invoc = if let Some(invoc) = invocations.pop() { |
| invoc |
| } else { |
| self.resolve_imports(); |
| if undetermined_invocations.is_empty() { break } |
| invocations = mem::replace(&mut undetermined_invocations, Vec::new()); |
| force = !mem::replace(&mut progress, false); |
| continue |
| }; |
| |
| let scope = |
| if self.monotonic { invoc.expansion_data.mark } else { orig_expansion_data.mark }; |
| let ext = match self.cx.resolver.resolve_macro_invocation(&invoc, scope, force) { |
| Ok(ext) => Some(ext), |
| Err(Determinacy::Determined) => None, |
| Err(Determinacy::Undetermined) => { |
| undetermined_invocations.push(invoc); |
| continue |
| } |
| }; |
| |
| progress = true; |
| let ExpansionData { depth, mark, .. } = invoc.expansion_data; |
| self.cx.current_expansion = invoc.expansion_data.clone(); |
| |
| self.cx.current_expansion.mark = scope; |
| // FIXME(jseyfried): Refactor out the following logic |
| let (expanded_fragment, new_invocations) = if let Some(ext) = ext { |
| if let Some(ext) = ext { |
| let (invoc_fragment_kind, invoc_span) = (invoc.fragment_kind, invoc.span()); |
| let fragment = self.expand_invoc(invoc, &*ext).unwrap_or_else(|| { |
| invoc_fragment_kind.dummy(invoc_span).unwrap() |
| }); |
| self.collect_invocations(fragment, &[]) |
| } else if let InvocationKind::Attr { attr: None, traits, item, .. } = invoc.kind { |
| if !item.derive_allowed() { |
| let attr = attr::find_by_name(item.attrs(), sym::derive) |
| .expect("`derive` attribute should exist"); |
| let span = attr.span; |
| let mut err = self.cx.mut_span_err(span, |
| "`derive` may only be applied to \ |
| structs, enums and unions"); |
| if let ast::AttrStyle::Inner = attr.style { |
| let trait_list = traits.iter() |
| .map(|t| t.to_string()).collect::<Vec<_>>(); |
| let suggestion = format!("#[derive({})]", trait_list.join(", ")); |
| err.span_suggestion( |
| span, "try an outer attribute", suggestion, |
| // We don't 𝑘𝑛𝑜𝑤 that the following item is an ADT |
| Applicability::MaybeIncorrect |
| ); |
| } |
| err.emit(); |
| } |
| |
| let mut item = self.fully_configure(item); |
| item.visit_attrs(|attrs| attrs.retain(|a| a.path != sym::derive)); |
| let mut item_with_markers = item.clone(); |
| add_derived_markers(&mut self.cx, item.span(), &traits, &mut item_with_markers); |
| let derives = derives.entry(invoc.expansion_data.mark).or_default(); |
| |
| derives.reserve(traits.len()); |
| invocations.reserve(traits.len()); |
| for path in &traits { |
| let mark = Mark::fresh(self.cx.current_expansion.mark); |
| derives.push(mark); |
| let item = match self.cx.resolver.resolve_macro_path( |
| path, MacroKind::Derive, Mark::root(), Vec::new(), false) { |
| Ok(ext) => match ext.kind { |
| SyntaxExtensionKind::LegacyDerive(..) => item_with_markers.clone(), |
| _ => item.clone(), |
| }, |
| _ => item.clone(), |
| }; |
| invocations.push(Invocation { |
| kind: InvocationKind::Derive { path: path.clone(), item }, |
| fragment_kind: invoc.fragment_kind, |
| expansion_data: ExpansionData { |
| mark, |
| ..invoc.expansion_data.clone() |
| }, |
| }); |
| } |
| let fragment = invoc.fragment_kind |
| .expect_from_annotatables(::std::iter::once(item_with_markers)); |
| self.collect_invocations(fragment, derives) |
| } else { |
| unreachable!() |
| } |
| } else { |
| self.collect_invocations(invoc.fragment_kind.dummy(invoc.span()).unwrap(), &[]) |
| }; |
| |
| if expanded_fragments.len() < depth { |
| expanded_fragments.push(Vec::new()); |
| } |
| expanded_fragments[depth - 1].push((mark, expanded_fragment)); |
| if !self.cx.ecfg.single_step { |
| invocations.extend(new_invocations.into_iter().rev()); |
| } |
| } |
| |
| self.cx.current_expansion = orig_expansion_data; |
| |
| // Finally incorporate all the expanded macros into the input AST fragment. |
| let mut placeholder_expander = PlaceholderExpander::new(self.cx, self.monotonic); |
| while let Some(expanded_fragments) = expanded_fragments.pop() { |
| for (mark, expanded_fragment) in expanded_fragments.into_iter().rev() { |
| let derives = derives.remove(&mark).unwrap_or_else(Vec::new); |
| placeholder_expander.add(NodeId::placeholder_from_mark(mark), |
| expanded_fragment, derives); |
| } |
| } |
| fragment_with_placeholders.mut_visit_with(&mut placeholder_expander); |
| fragment_with_placeholders |
| } |
| |
| fn resolve_imports(&mut self) { |
| if self.monotonic { |
| self.cx.resolver.resolve_imports(); |
| } |
| } |
| |
| /// Collects all macro invocations reachable at this time in this AST fragment, and replace |
| /// them with "placeholders" - dummy macro invocations with specially crafted `NodeId`s. |
| /// Then call into resolver that builds a skeleton ("reduced graph") of the fragment and |
| /// prepares data for resolving paths of macro invocations. |
| fn collect_invocations(&mut self, mut fragment: AstFragment, derives: &[Mark]) |
| -> (AstFragment, Vec<Invocation>) { |
| // Resolve `$crate`s in the fragment for pretty-printing. |
| self.cx.resolver.resolve_dollar_crates(&fragment); |
| |
| let invocations = { |
| let mut collector = InvocationCollector { |
| cfg: StripUnconfigured { |
| sess: self.cx.parse_sess, |
| features: self.cx.ecfg.features, |
| }, |
| cx: self.cx, |
| invocations: Vec::new(), |
| monotonic: self.monotonic, |
| }; |
| fragment.mut_visit_with(&mut collector); |
| collector.invocations |
| }; |
| |
| if self.monotonic { |
| self.cx.resolver.visit_ast_fragment_with_placeholders( |
| self.cx.current_expansion.mark, &fragment, derives); |
| } |
| |
| (fragment, invocations) |
| } |
| |
| fn fully_configure(&mut self, item: Annotatable) -> Annotatable { |
| let mut cfg = StripUnconfigured { |
| sess: self.cx.parse_sess, |
| features: self.cx.ecfg.features, |
| }; |
| // Since the item itself has already been configured by the InvocationCollector, |
| // we know that fold result vector will contain exactly one element |
| match item { |
| Annotatable::Item(item) => { |
| Annotatable::Item(cfg.flat_map_item(item).pop().unwrap()) |
| } |
| Annotatable::TraitItem(item) => { |
| Annotatable::TraitItem( |
| item.map(|item| cfg.flat_map_trait_item(item).pop().unwrap())) |
| } |
| Annotatable::ImplItem(item) => { |
| Annotatable::ImplItem(item.map(|item| cfg.flat_map_impl_item(item).pop().unwrap())) |
| } |
| Annotatable::ForeignItem(item) => { |
| Annotatable::ForeignItem( |
| item.map(|item| cfg.flat_map_foreign_item(item).pop().unwrap()) |
| ) |
| } |
| Annotatable::Stmt(stmt) => { |
| Annotatable::Stmt(stmt.map(|stmt| cfg.flat_map_stmt(stmt).pop().unwrap())) |
| } |
| Annotatable::Expr(mut expr) => { |
| Annotatable::Expr({ cfg.visit_expr(&mut expr); expr }) |
| } |
| } |
| } |
| |
| fn expand_invoc(&mut self, invoc: Invocation, ext: &SyntaxExtension) -> Option<AstFragment> { |
| if invoc.fragment_kind == AstFragmentKind::ForeignItems && |
| !self.cx.ecfg.macros_in_extern_enabled() { |
| if let SyntaxExtensionKind::NonMacroAttr { .. } = ext.kind {} else { |
| emit_feature_err(&self.cx.parse_sess, sym::macros_in_extern, |
| invoc.span(), GateIssue::Language, |
| "macro invocations in `extern {}` blocks are experimental"); |
| } |
| } |
| |
| let result = match invoc.kind { |
| InvocationKind::Bang { .. } => self.expand_bang_invoc(invoc, ext)?, |
| InvocationKind::Attr { .. } => self.expand_attr_invoc(invoc, ext)?, |
| InvocationKind::Derive { .. } => self.expand_derive_invoc(invoc, ext)?, |
| }; |
| |
| if self.cx.current_expansion.depth > self.cx.ecfg.recursion_limit { |
| let info = self.cx.current_expansion.mark.expn_info().unwrap(); |
| let suggested_limit = self.cx.ecfg.recursion_limit * 2; |
| let mut err = self.cx.struct_span_err(info.call_site, |
| &format!("recursion limit reached while expanding the macro `{}`", |
| info.format.name())); |
| err.help(&format!( |
| "consider adding a `#![recursion_limit=\"{}\"]` attribute to your crate", |
| suggested_limit)); |
| err.emit(); |
| self.cx.trace_macros_diag(); |
| FatalError.raise(); |
| } |
| |
| Some(result) |
| } |
| |
| fn expand_attr_invoc(&mut self, |
| invoc: Invocation, |
| ext: &SyntaxExtension) |
| -> Option<AstFragment> { |
| let (attr, mut item) = match invoc.kind { |
| InvocationKind::Attr { attr, item, .. } => (attr?, item), |
| _ => unreachable!(), |
| }; |
| |
| match &ext.kind { |
| SyntaxExtensionKind::NonMacroAttr { mark_used } => { |
| attr::mark_known(&attr); |
| if *mark_used { |
| attr::mark_used(&attr); |
| } |
| item.visit_attrs(|attrs| attrs.push(attr)); |
| Some(invoc.fragment_kind.expect_from_annotatables(iter::once(item))) |
| } |
| SyntaxExtensionKind::LegacyAttr(expander) => { |
| let meta = attr.parse_meta(self.cx.parse_sess) |
| .map_err(|mut e| { e.emit(); }).ok()?; |
| let item = expander.expand(self.cx, attr.span, &meta, item); |
| Some(invoc.fragment_kind.expect_from_annotatables(item)) |
| } |
| SyntaxExtensionKind::Attr(expander) => { |
| self.gate_proc_macro_attr_item(attr.span, &item); |
| let item_tok = TokenTree::token(token::Interpolated(Lrc::new(match item { |
| Annotatable::Item(item) => token::NtItem(item), |
| Annotatable::TraitItem(item) => token::NtTraitItem(item.into_inner()), |
| Annotatable::ImplItem(item) => token::NtImplItem(item.into_inner()), |
| Annotatable::ForeignItem(item) => token::NtForeignItem(item.into_inner()), |
| Annotatable::Stmt(stmt) => token::NtStmt(stmt.into_inner()), |
| Annotatable::Expr(expr) => token::NtExpr(expr), |
| })), DUMMY_SP).into(); |
| let input = self.extract_proc_macro_attr_input(attr.tokens, attr.span); |
| let tok_result = expander.expand(self.cx, attr.span, input, item_tok); |
| let res = self.parse_ast_fragment(tok_result, invoc.fragment_kind, |
| &attr.path, attr.span); |
| self.gate_proc_macro_expansion(attr.span, &res); |
| res |
| } |
| SyntaxExtensionKind::Derive(..) | SyntaxExtensionKind::LegacyDerive(..) => { |
| self.cx.span_err(attr.span, &format!("`{}` is a derive macro", attr.path)); |
| self.cx.trace_macros_diag(); |
| invoc.fragment_kind.dummy(attr.span) |
| } |
| _ => { |
| let msg = &format!("macro `{}` may not be used in attributes", attr.path); |
| self.cx.span_err(attr.span, msg); |
| self.cx.trace_macros_diag(); |
| invoc.fragment_kind.dummy(attr.span) |
| } |
| } |
| } |
| |
| fn extract_proc_macro_attr_input(&self, tokens: TokenStream, span: Span) -> TokenStream { |
| let mut trees = tokens.trees(); |
| match trees.next() { |
| Some(TokenTree::Delimited(_, _, tts)) => { |
| if trees.next().is_none() { |
| return tts.into() |
| } |
| } |
| Some(TokenTree::Token(..)) => {} |
| None => return TokenStream::empty(), |
| } |
| self.cx.span_err(span, "custom attribute invocations must be \ |
| of the form #[foo] or #[foo(..)], the macro name must only be \ |
| followed by a delimiter token"); |
| TokenStream::empty() |
| } |
| |
| fn gate_proc_macro_attr_item(&self, span: Span, item: &Annotatable) { |
| let (kind, gate) = match *item { |
| Annotatable::Item(ref item) => { |
| match item.node { |
| ItemKind::Mod(_) if self.cx.ecfg.proc_macro_hygiene() => return, |
| ItemKind::Mod(_) => ("modules", sym::proc_macro_hygiene), |
| _ => return, |
| } |
| } |
| Annotatable::TraitItem(_) => return, |
| Annotatable::ImplItem(_) => return, |
| Annotatable::ForeignItem(_) => return, |
| Annotatable::Stmt(_) | |
| Annotatable::Expr(_) if self.cx.ecfg.proc_macro_hygiene() => return, |
| Annotatable::Stmt(_) => ("statements", sym::proc_macro_hygiene), |
| Annotatable::Expr(_) => ("expressions", sym::proc_macro_hygiene), |
| }; |
| emit_feature_err( |
| self.cx.parse_sess, |
| gate, |
| span, |
| GateIssue::Language, |
| &format!("custom attributes cannot be applied to {}", kind), |
| ); |
| } |
| |
| fn gate_proc_macro_expansion(&self, span: Span, fragment: &Option<AstFragment>) { |
| if self.cx.ecfg.proc_macro_hygiene() { |
| return |
| } |
| let fragment = match fragment { |
| Some(fragment) => fragment, |
| None => return, |
| }; |
| |
| fragment.visit_with(&mut DisallowMacros { |
| span, |
| parse_sess: self.cx.parse_sess, |
| }); |
| |
| struct DisallowMacros<'a> { |
| span: Span, |
| parse_sess: &'a ParseSess, |
| } |
| |
| impl<'ast, 'a> Visitor<'ast> for DisallowMacros<'a> { |
| fn visit_item(&mut self, i: &'ast ast::Item) { |
| if let ast::ItemKind::MacroDef(_) = i.node { |
| emit_feature_err( |
| self.parse_sess, |
| sym::proc_macro_hygiene, |
| self.span, |
| GateIssue::Language, |
| "procedural macros cannot expand to macro definitions", |
| ); |
| } |
| visit::walk_item(self, i); |
| } |
| |
| fn visit_mac(&mut self, _mac: &'ast ast::Mac) { |
| // ... |
| } |
| } |
| } |
| |
| /// Expand a macro invocation. Returns the resulting expanded AST fragment. |
| fn expand_bang_invoc(&mut self, |
| invoc: Invocation, |
| ext: &SyntaxExtension) |
| -> Option<AstFragment> { |
| let kind = invoc.fragment_kind; |
| let (mac, ident, span) = match invoc.kind { |
| InvocationKind::Bang { mac, ident, span } => (mac, ident, span), |
| _ => unreachable!(), |
| }; |
| let path = &mac.node.path; |
| |
| let ident = ident.unwrap_or_else(|| Ident::invalid()); |
| let validate = |this: &mut Self| { |
| // feature-gate the macro invocation |
| if let Some((feature, issue)) = ext.unstable_feature { |
| let crate_span = this.cx.current_expansion.crate_span.unwrap(); |
| // don't stability-check macros in the same crate |
| // (the only time this is null is for syntax extensions registered as macros) |
| if ext.def_info.map_or(false, |(_, def_span)| !crate_span.contains(def_span)) |
| && !span.allows_unstable(feature) |
| && this.cx.ecfg.features.map_or(true, |feats| { |
| // macro features will count as lib features |
| !feats.declared_lib_features.iter().any(|&(feat, _)| feat == feature) |
| }) { |
| let explain = format!("macro {}! is unstable", path); |
| emit_feature_err(this.cx.parse_sess, feature, span, |
| GateIssue::Library(Some(issue)), &explain); |
| this.cx.trace_macros_diag(); |
| } |
| } |
| |
| if ident.name != kw::Invalid { |
| let msg = format!("macro {}! expects no ident argument, given '{}'", path, ident); |
| this.cx.span_err(path.span, &msg); |
| this.cx.trace_macros_diag(); |
| return Err(kind.dummy(span)); |
| } |
| Ok(()) |
| }; |
| |
| let opt_expanded = match &ext.kind { |
| SyntaxExtensionKind::LegacyBang(expander) => { |
| if let Err(dummy_span) = validate(self) { |
| dummy_span |
| } else { |
| kind.make_from(expander.expand( |
| self.cx, |
| span, |
| mac.node.stream(), |
| ext.def_info.map(|(_, s)| s), |
| )) |
| } |
| } |
| |
| SyntaxExtensionKind::Attr(..) | |
| SyntaxExtensionKind::LegacyAttr(..) | |
| SyntaxExtensionKind::NonMacroAttr { .. } => { |
| self.cx.span_err(path.span, |
| &format!("`{}` can only be used in attributes", path)); |
| self.cx.trace_macros_diag(); |
| kind.dummy(span) |
| } |
| |
| SyntaxExtensionKind::Derive(..) | SyntaxExtensionKind::LegacyDerive(..) => { |
| self.cx.span_err(path.span, &format!("`{}` is a derive macro", path)); |
| self.cx.trace_macros_diag(); |
| kind.dummy(span) |
| } |
| |
| SyntaxExtensionKind::Bang(expander) => { |
| if ident.name != kw::Invalid { |
| let msg = |
| format!("macro {}! expects no ident argument, given '{}'", path, ident); |
| self.cx.span_err(path.span, &msg); |
| self.cx.trace_macros_diag(); |
| kind.dummy(span) |
| } else { |
| self.gate_proc_macro_expansion_kind(span, kind); |
| let tok_result = expander.expand(self.cx, span, mac.node.stream()); |
| let result = self.parse_ast_fragment(tok_result, kind, path, span); |
| self.gate_proc_macro_expansion(span, &result); |
| result |
| } |
| } |
| }; |
| |
| if opt_expanded.is_some() { |
| opt_expanded |
| } else { |
| let msg = format!("non-{kind} macro in {kind} position: {name}", |
| name = path.segments[0].ident.name, kind = kind.name()); |
| self.cx.span_err(path.span, &msg); |
| self.cx.trace_macros_diag(); |
| kind.dummy(span) |
| } |
| } |
| |
| fn gate_proc_macro_expansion_kind(&self, span: Span, kind: AstFragmentKind) { |
| let kind = match kind { |
| AstFragmentKind::Expr => "expressions", |
| AstFragmentKind::OptExpr => "expressions", |
| AstFragmentKind::Pat => "patterns", |
| AstFragmentKind::Ty => "types", |
| AstFragmentKind::Stmts => "statements", |
| AstFragmentKind::Items => return, |
| AstFragmentKind::TraitItems => return, |
| AstFragmentKind::ImplItems => return, |
| AstFragmentKind::ForeignItems => return, |
| }; |
| if self.cx.ecfg.proc_macro_hygiene() { |
| return |
| } |
| emit_feature_err( |
| self.cx.parse_sess, |
| sym::proc_macro_hygiene, |
| span, |
| GateIssue::Language, |
| &format!("procedural macros cannot be expanded to {}", kind), |
| ); |
| } |
| |
| /// Expand a derive invocation. Returns the resulting expanded AST fragment. |
| fn expand_derive_invoc(&mut self, |
| invoc: Invocation, |
| ext: &SyntaxExtension) |
| -> Option<AstFragment> { |
| let (path, item) = match invoc.kind { |
| InvocationKind::Derive { path, item } => (path, item), |
| _ => unreachable!(), |
| }; |
| if !item.derive_allowed() { |
| return None; |
| } |
| |
| match &ext.kind { |
| SyntaxExtensionKind::Derive(expander) | |
| SyntaxExtensionKind::LegacyDerive(expander) => { |
| let meta = ast::MetaItem { node: ast::MetaItemKind::Word, span: path.span, path }; |
| let span = meta.span.with_ctxt(self.cx.backtrace()); |
| let items = expander.expand(self.cx, span, &meta, item); |
| Some(invoc.fragment_kind.expect_from_annotatables(items)) |
| } |
| _ => { |
| let msg = &format!("macro `{}` may not be used for derive attributes", path); |
| self.cx.span_err(path.span, msg); |
| self.cx.trace_macros_diag(); |
| invoc.fragment_kind.dummy(path.span) |
| } |
| } |
| } |
| |
| fn parse_ast_fragment(&mut self, |
| toks: TokenStream, |
| kind: AstFragmentKind, |
| path: &Path, |
| span: Span) |
| -> Option<AstFragment> { |
| let mut parser = self.cx.new_parser_from_tts(&toks.into_trees().collect::<Vec<_>>()); |
| match parser.parse_ast_fragment(kind, false) { |
| Ok(fragment) => { |
| parser.ensure_complete_parse(path, kind.name(), span); |
| Some(fragment) |
| } |
| Err(mut err) => { |
| err.set_span(span); |
| err.emit(); |
| self.cx.trace_macros_diag(); |
| kind.dummy(span) |
| } |
| } |
| } |
| } |
| |
| impl<'a> Parser<'a> { |
| pub fn parse_ast_fragment(&mut self, kind: AstFragmentKind, macro_legacy_warnings: bool) |
| -> PResult<'a, AstFragment> { |
| Ok(match kind { |
| AstFragmentKind::Items => { |
| let mut items = SmallVec::new(); |
| while let Some(item) = self.parse_item()? { |
| items.push(item); |
| } |
| AstFragment::Items(items) |
| } |
| AstFragmentKind::TraitItems => { |
| let mut items = SmallVec::new(); |
| while self.token != token::Eof { |
| items.push(self.parse_trait_item(&mut false)?); |
| } |
| AstFragment::TraitItems(items) |
| } |
| AstFragmentKind::ImplItems => { |
| let mut items = SmallVec::new(); |
| while self.token != token::Eof { |
| items.push(self.parse_impl_item(&mut false)?); |
| } |
| AstFragment::ImplItems(items) |
| } |
| AstFragmentKind::ForeignItems => { |
| let mut items = SmallVec::new(); |
| while self.token != token::Eof { |
| items.push(self.parse_foreign_item()?); |
| } |
| AstFragment::ForeignItems(items) |
| } |
| AstFragmentKind::Stmts => { |
| let mut stmts = SmallVec::new(); |
| while self.token != token::Eof && |
| // won't make progress on a `}` |
| self.token != token::CloseDelim(token::Brace) { |
| if let Some(stmt) = self.parse_full_stmt(macro_legacy_warnings)? { |
| stmts.push(stmt); |
| } |
| } |
| AstFragment::Stmts(stmts) |
| } |
| AstFragmentKind::Expr => AstFragment::Expr(self.parse_expr()?), |
| AstFragmentKind::OptExpr => { |
| if self.token != token::Eof { |
| AstFragment::OptExpr(Some(self.parse_expr()?)) |
| } else { |
| AstFragment::OptExpr(None) |
| } |
| }, |
| AstFragmentKind::Ty => AstFragment::Ty(self.parse_ty()?), |
| AstFragmentKind::Pat => AstFragment::Pat(self.parse_pat(None)?), |
| }) |
| } |
| |
| pub fn ensure_complete_parse(&mut self, macro_path: &Path, kind_name: &str, span: Span) { |
| if self.token != token::Eof { |
| let msg = format!("macro expansion ignores token `{}` and any following", |
| self.this_token_to_string()); |
| // Avoid emitting backtrace info twice. |
| let def_site_span = self.token.span.with_ctxt(SyntaxContext::empty()); |
| let mut err = self.diagnostic().struct_span_err(def_site_span, &msg); |
| err.span_label(span, "caused by the macro expansion here"); |
| let msg = format!( |
| "the usage of `{}!` is likely invalid in {} context", |
| macro_path, |
| kind_name, |
| ); |
| err.note(&msg); |
| let semi_span = self.sess.source_map().next_point(span); |
| |
| let semi_full_span = semi_span.to(self.sess.source_map().next_point(semi_span)); |
| match self.sess.source_map().span_to_snippet(semi_full_span) { |
| Ok(ref snippet) if &snippet[..] != ";" && kind_name == "expression" => { |
| err.span_suggestion( |
| semi_span, |
| "you might be missing a semicolon here", |
| ";".to_owned(), |
| Applicability::MaybeIncorrect, |
| ); |
| } |
| _ => {} |
| } |
| err.emit(); |
| } |
| } |
| } |
| |
| struct InvocationCollector<'a, 'b> { |
| cx: &'a mut ExtCtxt<'b>, |
| cfg: StripUnconfigured<'a>, |
| invocations: Vec<Invocation>, |
| monotonic: bool, |
| } |
| |
| impl<'a, 'b> InvocationCollector<'a, 'b> { |
| fn collect(&mut self, fragment_kind: AstFragmentKind, kind: InvocationKind) -> AstFragment { |
| let mark = Mark::fresh(self.cx.current_expansion.mark); |
| self.invocations.push(Invocation { |
| kind, |
| fragment_kind, |
| expansion_data: ExpansionData { |
| mark, |
| depth: self.cx.current_expansion.depth + 1, |
| ..self.cx.current_expansion.clone() |
| }, |
| }); |
| placeholder(fragment_kind, NodeId::placeholder_from_mark(mark)) |
| } |
| |
| fn collect_bang(&mut self, mac: ast::Mac, span: Span, kind: AstFragmentKind) -> AstFragment { |
| self.collect(kind, InvocationKind::Bang { mac, ident: None, span }) |
| } |
| |
| fn collect_attr(&mut self, |
| attr: Option<ast::Attribute>, |
| traits: Vec<Path>, |
| item: Annotatable, |
| kind: AstFragmentKind, |
| after_derive: bool) |
| -> AstFragment { |
| self.collect(kind, InvocationKind::Attr { attr, traits, item, after_derive }) |
| } |
| |
| fn find_attr_invoc(&self, attrs: &mut Vec<ast::Attribute>, after_derive: &mut bool) |
| -> Option<ast::Attribute> { |
| let attr = attrs.iter() |
| .position(|a| { |
| if a.path == sym::derive { |
| *after_derive = true; |
| } |
| !attr::is_known(a) && !is_builtin_attr(a) |
| }) |
| .map(|i| attrs.remove(i)); |
| if let Some(attr) = &attr { |
| if !self.cx.ecfg.enable_custom_inner_attributes() && |
| attr.style == ast::AttrStyle::Inner && attr.path != sym::test { |
| emit_feature_err(&self.cx.parse_sess, sym::custom_inner_attributes, |
| attr.span, GateIssue::Language, |
| "non-builtin inner attributes are unstable"); |
| } |
| } |
| attr |
| } |
| |
| /// If `item` is an attr invocation, remove and return the macro attribute and derive traits. |
| fn classify_item<T>(&mut self, item: &mut T) |
| -> (Option<ast::Attribute>, Vec<Path>, /* after_derive */ bool) |
| where T: HasAttrs, |
| { |
| let (mut attr, mut traits, mut after_derive) = (None, Vec::new(), false); |
| |
| item.visit_attrs(|mut attrs| { |
| attr = self.find_attr_invoc(&mut attrs, &mut after_derive); |
| traits = collect_derives(&mut self.cx, &mut attrs); |
| }); |
| |
| (attr, traits, after_derive) |
| } |
| |
| /// Alternative to `classify_item()` that ignores `#[derive]` so invocations fallthrough |
| /// to the unused-attributes lint (making it an error on statements and expressions |
| /// is a breaking change) |
| fn classify_nonitem<T: HasAttrs>(&mut self, nonitem: &mut T) |
| -> (Option<ast::Attribute>, /* after_derive */ bool) { |
| let (mut attr, mut after_derive) = (None, false); |
| |
| nonitem.visit_attrs(|mut attrs| { |
| attr = self.find_attr_invoc(&mut attrs, &mut after_derive); |
| }); |
| |
| (attr, after_derive) |
| } |
| |
| fn configure<T: HasAttrs>(&mut self, node: T) -> Option<T> { |
| self.cfg.configure(node) |
| } |
| |
| // Detect use of feature-gated or invalid attributes on macro invocations |
| // since they will not be detected after macro expansion. |
| fn check_attributes(&mut self, attrs: &[ast::Attribute]) { |
| let features = self.cx.ecfg.features.unwrap(); |
| for attr in attrs.iter() { |
| self.check_attribute_inner(attr, features); |
| |
| // macros are expanded before any lint passes so this warning has to be hardcoded |
| if attr.path == sym::derive { |
| self.cx.struct_span_warn(attr.span, "`#[derive]` does nothing on macro invocations") |
| .note("this may become a hard error in a future release") |
| .emit(); |
| } |
| } |
| } |
| |
| fn check_attribute(&mut self, at: &ast::Attribute) { |
| let features = self.cx.ecfg.features.unwrap(); |
| self.check_attribute_inner(at, features); |
| } |
| |
| fn check_attribute_inner(&mut self, at: &ast::Attribute, features: &Features) { |
| feature_gate::check_attribute(at, self.cx.parse_sess, features); |
| } |
| } |
| |
| impl<'a, 'b> MutVisitor for InvocationCollector<'a, 'b> { |
| fn visit_expr(&mut self, expr: &mut P<ast::Expr>) { |
| self.cfg.configure_expr(expr); |
| visit_clobber(expr.deref_mut(), |mut expr| { |
| self.cfg.configure_expr_kind(&mut expr.node); |
| |
| // ignore derives so they remain unused |
| let (attr, after_derive) = self.classify_nonitem(&mut expr); |
| |
| if attr.is_some() { |
| // Collect the invoc regardless of whether or not attributes are permitted here |
| // expansion will eat the attribute so it won't error later. |
| attr.as_ref().map(|a| self.cfg.maybe_emit_expr_attr_err(a)); |
| |
| // AstFragmentKind::Expr requires the macro to emit an expression. |
| return self.collect_attr(attr, vec![], Annotatable::Expr(P(expr)), |
| AstFragmentKind::Expr, after_derive) |
| .make_expr() |
| .into_inner() |
| } |
| |
| if let ast::ExprKind::Mac(mac) = expr.node { |
| self.check_attributes(&expr.attrs); |
| self.collect_bang(mac, expr.span, AstFragmentKind::Expr) |
| .make_expr() |
| .into_inner() |
| } else { |
| noop_visit_expr(&mut expr, self); |
| expr |
| } |
| }); |
| } |
| |
| fn filter_map_expr(&mut self, expr: P<ast::Expr>) -> Option<P<ast::Expr>> { |
| let expr = configure!(self, expr); |
| expr.filter_map(|mut expr| { |
| self.cfg.configure_expr_kind(&mut expr.node); |
| |
| // Ignore derives so they remain unused. |
| let (attr, after_derive) = self.classify_nonitem(&mut expr); |
| |
| if attr.is_some() { |
| attr.as_ref().map(|a| self.cfg.maybe_emit_expr_attr_err(a)); |
| |
| return self.collect_attr(attr, vec![], Annotatable::Expr(P(expr)), |
| AstFragmentKind::OptExpr, after_derive) |
| .make_opt_expr() |
| .map(|expr| expr.into_inner()) |
| } |
| |
| if let ast::ExprKind::Mac(mac) = expr.node { |
| self.check_attributes(&expr.attrs); |
| self.collect_bang(mac, expr.span, AstFragmentKind::OptExpr) |
| .make_opt_expr() |
| .map(|expr| expr.into_inner()) |
| } else { |
| Some({ noop_visit_expr(&mut expr, self); expr }) |
| } |
| }) |
| } |
| |
| fn visit_pat(&mut self, pat: &mut P<ast::Pat>) { |
| self.cfg.configure_pat(pat); |
| match pat.node { |
| PatKind::Mac(_) => {} |
| _ => return noop_visit_pat(pat, self), |
| } |
| |
| visit_clobber(pat, |mut pat| { |
| match mem::replace(&mut pat.node, PatKind::Wild) { |
| PatKind::Mac(mac) => |
| self.collect_bang(mac, pat.span, AstFragmentKind::Pat).make_pat(), |
| _ => unreachable!(), |
| } |
| }); |
| } |
| |
| fn flat_map_stmt(&mut self, stmt: ast::Stmt) -> SmallVec<[ast::Stmt; 1]> { |
| let mut stmt = configure!(self, stmt); |
| |
| // we'll expand attributes on expressions separately |
| if !stmt.is_expr() { |
| let (attr, derives, after_derive) = if stmt.is_item() { |
| self.classify_item(&mut stmt) |
| } else { |
| // ignore derives on non-item statements so it falls through |
| // to the unused-attributes lint |
| let (attr, after_derive) = self.classify_nonitem(&mut stmt); |
| (attr, vec![], after_derive) |
| }; |
| |
| if attr.is_some() || !derives.is_empty() { |
| return self.collect_attr(attr, derives, Annotatable::Stmt(P(stmt)), |
| AstFragmentKind::Stmts, after_derive).make_stmts(); |
| } |
| } |
| |
| if let StmtKind::Mac(mac) = stmt.node { |
| let (mac, style, attrs) = mac.into_inner(); |
| self.check_attributes(&attrs); |
| let mut placeholder = self.collect_bang(mac, stmt.span, AstFragmentKind::Stmts) |
| .make_stmts(); |
| |
| // If this is a macro invocation with a semicolon, then apply that |
| // semicolon to the final statement produced by expansion. |
| if style == MacStmtStyle::Semicolon { |
| if let Some(stmt) = placeholder.pop() { |
| placeholder.push(stmt.add_trailing_semicolon()); |
| } |
| } |
| |
| return placeholder; |
| } |
| |
| // The placeholder expander gives ids to statements, so we avoid folding the id here. |
| let ast::Stmt { id, node, span } = stmt; |
| noop_flat_map_stmt_kind(node, self).into_iter().map(|node| { |
| ast::Stmt { id, node, span } |
| }).collect() |
| |
| } |
| |
| fn visit_block(&mut self, block: &mut P<Block>) { |
| let old_directory_ownership = self.cx.current_expansion.directory_ownership; |
| self.cx.current_expansion.directory_ownership = DirectoryOwnership::UnownedViaBlock; |
| noop_visit_block(block, self); |
| self.cx.current_expansion.directory_ownership = old_directory_ownership; |
| } |
| |
| fn flat_map_item(&mut self, item: P<ast::Item>) -> SmallVec<[P<ast::Item>; 1]> { |
| let mut item = configure!(self, item); |
| |
| let (attr, traits, after_derive) = self.classify_item(&mut item); |
| if attr.is_some() || !traits.is_empty() { |
| return self.collect_attr(attr, traits, Annotatable::Item(item), |
| AstFragmentKind::Items, after_derive).make_items(); |
| } |
| |
| match item.node { |
| ast::ItemKind::Mac(..) => { |
| self.check_attributes(&item.attrs); |
| item.and_then(|item| match item.node { |
| ItemKind::Mac(mac) => { |
| self.collect(AstFragmentKind::Items, InvocationKind::Bang { |
| mac, |
| ident: Some(item.ident), |
| span: item.span, |
| }).make_items() |
| } |
| _ => unreachable!(), |
| }) |
| } |
| ast::ItemKind::Mod(ast::Mod { inner, .. }) => { |
| if item.ident == Ident::invalid() { |
| return noop_flat_map_item(item, self); |
| } |
| |
| let orig_directory_ownership = self.cx.current_expansion.directory_ownership; |
| let mut module = (*self.cx.current_expansion.module).clone(); |
| module.mod_path.push(item.ident); |
| |
| // Detect if this is an inline module (`mod m { ... }` as opposed to `mod m;`). |
| // In the non-inline case, `inner` is never the dummy span (cf. `parse_item_mod`). |
| // Thus, if `inner` is the dummy span, we know the module is inline. |
| let inline_module = item.span.contains(inner) || inner.is_dummy(); |
| |
| if inline_module { |
| if let Some(path) = attr::first_attr_value_str_by_name(&item.attrs, sym::path) { |
| self.cx.current_expansion.directory_ownership = |
| DirectoryOwnership::Owned { relative: None }; |
| module.directory.push(&*path.as_str()); |
| } else { |
| module.directory.push(&*item.ident.as_str()); |
| } |
| } else { |
| let path = self.cx.parse_sess.source_map().span_to_unmapped_path(inner); |
| let mut path = match path { |
| FileName::Real(path) => path, |
| other => PathBuf::from(other.to_string()), |
| }; |
| let directory_ownership = match path.file_name().unwrap().to_str() { |
| Some("mod.rs") => DirectoryOwnership::Owned { relative: None }, |
| Some(_) => DirectoryOwnership::Owned { |
| relative: Some(item.ident), |
| }, |
| None => DirectoryOwnership::UnownedViaMod(false), |
| }; |
| path.pop(); |
| module.directory = path; |
| self.cx.current_expansion.directory_ownership = directory_ownership; |
| } |
| |
| let orig_module = |
| mem::replace(&mut self.cx.current_expansion.module, Rc::new(module)); |
| let result = noop_flat_map_item(item, self); |
| self.cx.current_expansion.module = orig_module; |
| self.cx.current_expansion.directory_ownership = orig_directory_ownership; |
| result |
| } |
| |
| _ => noop_flat_map_item(item, self), |
| } |
| } |
| |
| fn flat_map_trait_item(&mut self, item: ast::TraitItem) -> SmallVec<[ast::TraitItem; 1]> { |
| let mut item = configure!(self, item); |
| |
| let (attr, traits, after_derive) = self.classify_item(&mut item); |
| if attr.is_some() || !traits.is_empty() { |
| return self.collect_attr(attr, traits, Annotatable::TraitItem(P(item)), |
| AstFragmentKind::TraitItems, after_derive).make_trait_items() |
| } |
| |
| match item.node { |
| ast::TraitItemKind::Macro(mac) => { |
| let ast::TraitItem { attrs, span, .. } = item; |
| self.check_attributes(&attrs); |
| self.collect_bang(mac, span, AstFragmentKind::TraitItems).make_trait_items() |
| } |
| _ => noop_flat_map_trait_item(item, self), |
| } |
| } |
| |
| fn flat_map_impl_item(&mut self, item: ast::ImplItem) -> SmallVec<[ast::ImplItem; 1]> { |
| let mut item = configure!(self, item); |
| |
| let (attr, traits, after_derive) = self.classify_item(&mut item); |
| if attr.is_some() || !traits.is_empty() { |
| return self.collect_attr(attr, traits, Annotatable::ImplItem(P(item)), |
| AstFragmentKind::ImplItems, after_derive).make_impl_items(); |
| } |
| |
| match item.node { |
| ast::ImplItemKind::Macro(mac) => { |
| let ast::ImplItem { attrs, span, .. } = item; |
| self.check_attributes(&attrs); |
| self.collect_bang(mac, span, AstFragmentKind::ImplItems).make_impl_items() |
| } |
| _ => noop_flat_map_impl_item(item, self), |
| } |
| } |
| |
| fn visit_ty(&mut self, ty: &mut P<ast::Ty>) { |
| match ty.node { |
| ast::TyKind::Mac(_) => {} |
| _ => return noop_visit_ty(ty, self), |
| }; |
| |
| visit_clobber(ty, |mut ty| { |
| match mem::replace(&mut ty.node, ast::TyKind::Err) { |
| ast::TyKind::Mac(mac) => |
| self.collect_bang(mac, ty.span, AstFragmentKind::Ty).make_ty(), |
| _ => unreachable!(), |
| } |
| }); |
| } |
| |
| fn visit_foreign_mod(&mut self, foreign_mod: &mut ast::ForeignMod) { |
| self.cfg.configure_foreign_mod(foreign_mod); |
| noop_visit_foreign_mod(foreign_mod, self); |
| } |
| |
| fn flat_map_foreign_item(&mut self, mut foreign_item: ast::ForeignItem) |
| -> SmallVec<[ast::ForeignItem; 1]> |
| { |
| let (attr, traits, after_derive) = self.classify_item(&mut foreign_item); |
| |
| if attr.is_some() || !traits.is_empty() { |
| return self.collect_attr(attr, traits, Annotatable::ForeignItem(P(foreign_item)), |
| AstFragmentKind::ForeignItems, after_derive) |
| .make_foreign_items(); |
| } |
| |
| if let ast::ForeignItemKind::Macro(mac) = foreign_item.node { |
| self.check_attributes(&foreign_item.attrs); |
| return self.collect_bang(mac, foreign_item.span, AstFragmentKind::ForeignItems) |
| .make_foreign_items(); |
| } |
| |
| noop_flat_map_foreign_item(foreign_item, self) |
| } |
| |
| fn visit_item_kind(&mut self, item: &mut ast::ItemKind) { |
| match item { |
| ast::ItemKind::MacroDef(..) => {} |
| _ => { |
| self.cfg.configure_item_kind(item); |
| noop_visit_item_kind(item, self); |
| } |
| } |
| } |
| |
| fn visit_generic_params(&mut self, params: &mut Vec<ast::GenericParam>) { |
| self.cfg.configure_generic_params(params); |
| noop_visit_generic_params(params, self); |
| } |
| |
| fn visit_attribute(&mut self, at: &mut ast::Attribute) { |
| // turn `#[doc(include="filename")]` attributes into `#[doc(include(file="filename", |
| // contents="file contents")]` attributes |
| if !at.check_name(sym::doc) { |
| return noop_visit_attribute(at, self); |
| } |
| |
| if let Some(list) = at.meta_item_list() { |
| if !list.iter().any(|it| it.check_name(sym::include)) { |
| return noop_visit_attribute(at, self); |
| } |
| |
| let mut items = vec![]; |
| |
| for mut it in list { |
| if !it.check_name(sym::include) { |
| items.push({ noop_visit_meta_list_item(&mut it, self); it }); |
| continue; |
| } |
| |
| if let Some(file) = it.value_str() { |
| let err_count = self.cx.parse_sess.span_diagnostic.err_count(); |
| self.check_attribute(&at); |
| if self.cx.parse_sess.span_diagnostic.err_count() > err_count { |
| // avoid loading the file if they haven't enabled the feature |
| return noop_visit_attribute(at, self); |
| } |
| |
| let filename = self.cx.root_path.join(file.to_string()); |
| match fs::read_to_string(&filename) { |
| Ok(src) => { |
| let src_interned = Symbol::intern(&src); |
| |
| // Add this input file to the code map to make it available as |
| // dependency information |
| self.cx.source_map().new_source_file(filename.into(), src); |
| |
| let include_info = vec![ |
| ast::NestedMetaItem::MetaItem( |
| attr::mk_name_value_item_str( |
| Ident::with_empty_ctxt(sym::file), |
| dummy_spanned(file), |
| ), |
| ), |
| ast::NestedMetaItem::MetaItem( |
| attr::mk_name_value_item_str( |
| Ident::with_empty_ctxt(sym::contents), |
| dummy_spanned(src_interned), |
| ), |
| ), |
| ]; |
| |
| let include_ident = Ident::with_empty_ctxt(sym::include); |
| let item = attr::mk_list_item(DUMMY_SP, include_ident, include_info); |
| items.push(ast::NestedMetaItem::MetaItem(item)); |
| } |
| Err(e) => { |
| let lit = it |
| .meta_item() |
| .and_then(|item| item.name_value_literal()) |
| .unwrap(); |
| |
| if e.kind() == ErrorKind::InvalidData { |
| self.cx |
| .struct_span_err( |
| lit.span, |
| &format!("{} wasn't a utf-8 file", filename.display()), |
| ) |
| .span_label(lit.span, "contains invalid utf-8") |
| .emit(); |
| } else { |
| let mut err = self.cx.struct_span_err( |
| lit.span, |
| &format!("couldn't read {}: {}", filename.display(), e), |
| ); |
| err.span_label(lit.span, "couldn't read file"); |
| |
| if e.kind() == ErrorKind::NotFound { |
| err.help("external doc paths are relative to the crate root"); |
| } |
| |
| err.emit(); |
| } |
| } |
| } |
| } else { |
| let mut err = self.cx.struct_span_err( |
| it.span(), |
| &format!("expected path to external documentation"), |
| ); |
| |
| // Check if the user erroneously used `doc(include(...))` syntax. |
| let literal = it.meta_item_list().and_then(|list| { |
| if list.len() == 1 { |
| list[0].literal().map(|literal| &literal.node) |
| } else { |
| None |
| } |
| }); |
| |
| let (path, applicability) = match &literal { |
| Some(LitKind::Str(path, ..)) => { |
| (path.to_string(), Applicability::MachineApplicable) |
| } |
| _ => (String::from("<path>"), Applicability::HasPlaceholders), |
| }; |
| |
| err.span_suggestion( |
| it.span(), |
| "provide a file path with `=`", |
| format!("include = \"{}\"", path), |
| applicability, |
| ); |
| |
| err.emit(); |
| } |
| } |
| |
| let meta = attr::mk_list_item(DUMMY_SP, Ident::with_empty_ctxt(sym::doc), items); |
| match at.style { |
| ast::AttrStyle::Inner => *at = attr::mk_spanned_attr_inner(at.span, at.id, meta), |
| ast::AttrStyle::Outer => *at = attr::mk_spanned_attr_outer(at.span, at.id, meta), |
| } |
| } else { |
| noop_visit_attribute(at, self) |
| } |
| } |
| |
| fn visit_id(&mut self, id: &mut ast::NodeId) { |
| if self.monotonic { |
| debug_assert_eq!(*id, ast::DUMMY_NODE_ID); |
| *id = self.cx.resolver.next_node_id() |
| } |
| } |
| |
| fn visit_fn_decl(&mut self, mut fn_decl: &mut P<ast::FnDecl>) { |
| self.cfg.configure_fn_decl(&mut fn_decl); |
| noop_visit_fn_decl(fn_decl, self); |
| } |
| } |
| |
| pub struct ExpansionConfig<'feat> { |
| pub crate_name: String, |
| pub features: Option<&'feat Features>, |
| pub recursion_limit: usize, |
| pub trace_mac: bool, |
| pub should_test: bool, // If false, strip `#[test]` nodes |
| pub single_step: bool, |
| pub keep_macs: bool, |
| } |
| |
| macro_rules! feature_tests { |
| ($( fn $getter:ident = $field:ident, )*) => { |
| $( |
| pub fn $getter(&self) -> bool { |
| match self.features { |
| Some(&Features { $field: true, .. }) => true, |
| _ => false, |
| } |
| } |
| )* |
| } |
| } |
| |
| impl<'feat> ExpansionConfig<'feat> { |
| pub fn default(crate_name: String) -> ExpansionConfig<'static> { |
| ExpansionConfig { |
| crate_name, |
| features: None, |
| recursion_limit: 1024, |
| trace_mac: false, |
| should_test: false, |
| single_step: false, |
| keep_macs: false, |
| } |
| } |
| |
| feature_tests! { |
| fn enable_asm = asm, |
| fn enable_custom_test_frameworks = custom_test_frameworks, |
| fn enable_global_asm = global_asm, |
| fn enable_log_syntax = log_syntax, |
| fn enable_concat_idents = concat_idents, |
| fn enable_trace_macros = trace_macros, |
| fn enable_allow_internal_unstable = allow_internal_unstable, |
| fn enable_format_args_nl = format_args_nl, |
| fn macros_in_extern_enabled = macros_in_extern, |
| fn proc_macro_hygiene = proc_macro_hygiene, |
| } |
| |
| fn enable_custom_inner_attributes(&self) -> bool { |
| self.features.map_or(false, |features| { |
| features.custom_inner_attributes || features.custom_attribute || features.rustc_attrs |
| }) |
| } |
| } |
| |
| // A Marker adds the given mark to the syntax context. |
| #[derive(Debug)] |
| pub struct Marker(pub Mark); |
| |
| impl MutVisitor for Marker { |
| fn visit_span(&mut self, span: &mut Span) { |
| *span = span.apply_mark(self.0) |
| } |
| |
| fn visit_mac(&mut self, mac: &mut ast::Mac) { |
| noop_visit_mac(mac, self) |
| } |
| } |