1842 lines
71 KiB
Rust
1842 lines
71 KiB
Rust
use crate::base::*;
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use crate::config::StripUnconfigured;
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use crate::configure;
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use crate::hygiene::{ExpnData, ExpnId, ExpnKind, SyntaxContext};
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use crate::mbe::macro_rules::annotate_err_with_kind;
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use crate::module::{parse_external_mod, push_directory, Directory, DirectoryOwnership};
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use crate::placeholders::{placeholder, PlaceholderExpander};
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use crate::proc_macro::collect_derives;
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use rustc_ast::ast::{self, AttrItem, Block, LitKind, NodeId, PatKind, Path};
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use rustc_ast::ast::{ItemKind, MacArgs, MacStmtStyle, StmtKind};
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use rustc_ast::mut_visit::*;
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use rustc_ast::ptr::P;
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use rustc_ast::token;
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use rustc_ast::tokenstream::TokenStream;
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use rustc_ast::visit::{self, AssocCtxt, Visitor};
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use rustc_ast_pretty::pprust;
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use rustc_attr::{self as attr, is_builtin_attr, HasAttrs};
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use rustc_data_structures::map_in_place::MapInPlace;
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use rustc_errors::{Applicability, PResult};
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use rustc_feature::Features;
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use rustc_parse::parser::Parser;
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use rustc_parse::validate_attr;
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use rustc_session::lint::builtin::UNUSED_DOC_COMMENTS;
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use rustc_session::lint::BuiltinLintDiagnostics;
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use rustc_session::parse::{feature_err, ParseSess};
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use rustc_span::source_map::respan;
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use rustc_span::symbol::{sym, Ident, Symbol};
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use rustc_span::{FileName, Span, DUMMY_SP};
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use smallvec::{smallvec, SmallVec};
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use std::io::ErrorKind;
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use std::ops::DerefMut;
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use std::path::PathBuf;
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use std::rc::Rc;
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use std::{iter, mem, slice};
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macro_rules! ast_fragments {
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(
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$($Kind:ident($AstTy:ty) {
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$kind_name:expr;
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$(one fn $mut_visit_ast:ident; fn $visit_ast:ident;)?
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$(many fn $flat_map_ast_elt:ident; fn $visit_ast_elt:ident($($args:tt)*);)?
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fn $make_ast:ident;
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})*
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) => {
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/// A fragment of AST that can be produced by a single macro expansion.
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/// Can also serve as an input and intermediate result for macro expansion operations.
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pub enum AstFragment {
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OptExpr(Option<P<ast::Expr>>),
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$($Kind($AstTy),)*
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}
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/// "Discriminant" of an AST fragment.
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#[derive(Copy, Clone, PartialEq, Eq)]
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pub enum AstFragmentKind {
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OptExpr,
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$($Kind,)*
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}
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impl AstFragmentKind {
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pub fn name(self) -> &'static str {
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match self {
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AstFragmentKind::OptExpr => "expression",
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$(AstFragmentKind::$Kind => $kind_name,)*
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}
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}
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fn make_from<'a>(self, result: Box<dyn MacResult + 'a>) -> Option<AstFragment> {
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match self {
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AstFragmentKind::OptExpr =>
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result.make_expr().map(Some).map(AstFragment::OptExpr),
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$(AstFragmentKind::$Kind => result.$make_ast().map(AstFragment::$Kind),)*
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}
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}
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}
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impl AstFragment {
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pub fn add_placeholders(&mut self, placeholders: &[NodeId]) {
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if placeholders.is_empty() {
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return;
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}
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match self {
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$($(AstFragment::$Kind(ast) => ast.extend(placeholders.iter().flat_map(|id| {
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// We are repeating through arguments with `many`, to do that we have to
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// mention some macro variable from those arguments even if it's not used.
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macro _repeating($flat_map_ast_elt) {}
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placeholder(AstFragmentKind::$Kind, *id, None).$make_ast()
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})),)?)*
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_ => panic!("unexpected AST fragment kind")
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}
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}
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pub fn make_opt_expr(self) -> Option<P<ast::Expr>> {
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match self {
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AstFragment::OptExpr(expr) => expr,
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_ => panic!("AstFragment::make_* called on the wrong kind of fragment"),
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}
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}
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$(pub fn $make_ast(self) -> $AstTy {
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match self {
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AstFragment::$Kind(ast) => ast,
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_ => panic!("AstFragment::make_* called on the wrong kind of fragment"),
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}
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})*
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pub fn mut_visit_with<F: MutVisitor>(&mut self, vis: &mut F) {
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match self {
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AstFragment::OptExpr(opt_expr) => {
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visit_clobber(opt_expr, |opt_expr| {
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if let Some(expr) = opt_expr {
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vis.filter_map_expr(expr)
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} else {
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None
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}
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});
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}
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$($(AstFragment::$Kind(ast) => vis.$mut_visit_ast(ast),)?)*
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$($(AstFragment::$Kind(ast) =>
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ast.flat_map_in_place(|ast| vis.$flat_map_ast_elt(ast)),)?)*
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}
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}
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pub fn visit_with<'a, V: Visitor<'a>>(&'a self, visitor: &mut V) {
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match *self {
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AstFragment::OptExpr(Some(ref expr)) => visitor.visit_expr(expr),
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AstFragment::OptExpr(None) => {}
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$($(AstFragment::$Kind(ref ast) => visitor.$visit_ast(ast),)?)*
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$($(AstFragment::$Kind(ref ast) => for ast_elt in &ast[..] {
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visitor.$visit_ast_elt(ast_elt, $($args)*);
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})?)*
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}
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}
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}
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impl<'a> MacResult for crate::mbe::macro_rules::ParserAnyMacro<'a> {
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$(fn $make_ast(self: Box<crate::mbe::macro_rules::ParserAnyMacro<'a>>)
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-> Option<$AstTy> {
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Some(self.make(AstFragmentKind::$Kind).$make_ast())
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})*
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}
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}
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}
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ast_fragments! {
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Expr(P<ast::Expr>) { "expression"; one fn visit_expr; fn visit_expr; fn make_expr; }
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Pat(P<ast::Pat>) { "pattern"; one fn visit_pat; fn visit_pat; fn make_pat; }
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Ty(P<ast::Ty>) { "type"; one fn visit_ty; fn visit_ty; fn make_ty; }
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Stmts(SmallVec<[ast::Stmt; 1]>) {
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"statement"; many fn flat_map_stmt; fn visit_stmt(); fn make_stmts;
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}
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Items(SmallVec<[P<ast::Item>; 1]>) {
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"item"; many fn flat_map_item; fn visit_item(); fn make_items;
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}
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TraitItems(SmallVec<[P<ast::AssocItem>; 1]>) {
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"trait item";
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many fn flat_map_trait_item;
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fn visit_assoc_item(AssocCtxt::Trait);
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fn make_trait_items;
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}
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ImplItems(SmallVec<[P<ast::AssocItem>; 1]>) {
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"impl item";
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many fn flat_map_impl_item;
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fn visit_assoc_item(AssocCtxt::Impl);
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fn make_impl_items;
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}
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ForeignItems(SmallVec<[P<ast::ForeignItem>; 1]>) {
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"foreign item";
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many fn flat_map_foreign_item;
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fn visit_foreign_item();
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fn make_foreign_items;
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}
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Arms(SmallVec<[ast::Arm; 1]>) {
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"match arm"; many fn flat_map_arm; fn visit_arm(); fn make_arms;
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}
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Fields(SmallVec<[ast::Field; 1]>) {
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"field expression"; many fn flat_map_field; fn visit_field(); fn make_fields;
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}
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FieldPats(SmallVec<[ast::FieldPat; 1]>) {
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"field pattern";
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many fn flat_map_field_pattern;
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fn visit_field_pattern();
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fn make_field_patterns;
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}
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GenericParams(SmallVec<[ast::GenericParam; 1]>) {
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"generic parameter";
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many fn flat_map_generic_param;
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fn visit_generic_param();
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fn make_generic_params;
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}
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Params(SmallVec<[ast::Param; 1]>) {
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"function parameter"; many fn flat_map_param; fn visit_param(); fn make_params;
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}
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StructFields(SmallVec<[ast::StructField; 1]>) {
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"field";
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many fn flat_map_struct_field;
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fn visit_struct_field();
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fn make_struct_fields;
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}
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Variants(SmallVec<[ast::Variant; 1]>) {
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"variant"; many fn flat_map_variant; fn visit_variant(); fn make_variants;
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}
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}
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impl AstFragmentKind {
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crate fn dummy(self, span: Span) -> AstFragment {
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self.make_from(DummyResult::any(span)).expect("couldn't create a dummy AST fragment")
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}
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fn expect_from_annotatables<I: IntoIterator<Item = Annotatable>>(
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self,
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items: I,
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) -> AstFragment {
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let mut items = items.into_iter();
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match self {
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AstFragmentKind::Arms => {
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AstFragment::Arms(items.map(Annotatable::expect_arm).collect())
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}
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AstFragmentKind::Fields => {
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AstFragment::Fields(items.map(Annotatable::expect_field).collect())
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}
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AstFragmentKind::FieldPats => {
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AstFragment::FieldPats(items.map(Annotatable::expect_field_pattern).collect())
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}
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AstFragmentKind::GenericParams => {
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AstFragment::GenericParams(items.map(Annotatable::expect_generic_param).collect())
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}
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AstFragmentKind::Params => {
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AstFragment::Params(items.map(Annotatable::expect_param).collect())
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}
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AstFragmentKind::StructFields => {
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AstFragment::StructFields(items.map(Annotatable::expect_struct_field).collect())
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}
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AstFragmentKind::Variants => {
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AstFragment::Variants(items.map(Annotatable::expect_variant).collect())
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}
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AstFragmentKind::Items => {
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AstFragment::Items(items.map(Annotatable::expect_item).collect())
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}
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AstFragmentKind::ImplItems => {
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AstFragment::ImplItems(items.map(Annotatable::expect_impl_item).collect())
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}
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AstFragmentKind::TraitItems => {
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AstFragment::TraitItems(items.map(Annotatable::expect_trait_item).collect())
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}
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AstFragmentKind::ForeignItems => {
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AstFragment::ForeignItems(items.map(Annotatable::expect_foreign_item).collect())
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}
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AstFragmentKind::Stmts => {
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AstFragment::Stmts(items.map(Annotatable::expect_stmt).collect())
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}
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AstFragmentKind::Expr => AstFragment::Expr(
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items.next().expect("expected exactly one expression").expect_expr(),
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),
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AstFragmentKind::OptExpr => {
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AstFragment::OptExpr(items.next().map(Annotatable::expect_expr))
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}
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AstFragmentKind::Pat | AstFragmentKind::Ty => {
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panic!("patterns and types aren't annotatable")
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}
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}
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}
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}
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pub struct Invocation {
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pub kind: InvocationKind,
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pub fragment_kind: AstFragmentKind,
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pub expansion_data: ExpansionData,
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}
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pub enum InvocationKind {
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Bang {
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mac: ast::MacCall,
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span: Span,
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},
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Attr {
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attr: ast::Attribute,
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item: Annotatable,
|
||
// Required for resolving derive helper attributes.
|
||
derives: Vec<Path>,
|
||
// We temporarily report errors for attribute macros placed after derives
|
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after_derive: bool,
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},
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Derive {
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path: Path,
|
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item: Annotatable,
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||
},
|
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/// "Invocation" that contains all derives from an item,
|
||
/// broken into multiple `Derive` invocations when expanded.
|
||
/// FIXME: Find a way to remove it.
|
||
DeriveContainer {
|
||
derives: Vec<Path>,
|
||
item: Annotatable,
|
||
},
|
||
}
|
||
|
||
impl InvocationKind {
|
||
fn placeholder_visibility(&self) -> Option<ast::Visibility> {
|
||
// HACK: For unnamed fields placeholders should have the same visibility as the actual
|
||
// fields because for tuple structs/variants resolve determines visibilities of their
|
||
// constructor using these field visibilities before attributes on them are are expanded.
|
||
// The assumption is that the attribute expansion cannot change field visibilities,
|
||
// and it holds because only inert attributes are supported in this position.
|
||
match self {
|
||
InvocationKind::Attr { item: Annotatable::StructField(field), .. }
|
||
| InvocationKind::Derive { item: Annotatable::StructField(field), .. }
|
||
| InvocationKind::DeriveContainer { item: Annotatable::StructField(field), .. }
|
||
if field.ident.is_none() =>
|
||
{
|
||
Some(field.vis.clone())
|
||
}
|
||
_ => None,
|
||
}
|
||
}
|
||
}
|
||
|
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impl Invocation {
|
||
pub fn span(&self) -> Span {
|
||
match &self.kind {
|
||
InvocationKind::Bang { span, .. } => *span,
|
||
InvocationKind::Attr { attr, .. } => attr.span,
|
||
InvocationKind::Derive { path, .. } => path.span,
|
||
InvocationKind::DeriveContainer { item, .. } => item.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);
|
||
|
||
let orig_mod_span = krate.module.inner;
|
||
|
||
let krate_item = AstFragment::Items(smallvec![P(ast::Item {
|
||
attrs: krate.attrs,
|
||
span: krate.span,
|
||
kind: 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.fully_expand_fragment(krate_item).make_items().pop().map(P::into_inner) {
|
||
Some(ast::Item { attrs, kind: 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 };
|
||
}
|
||
Some(ast::Item { span, kind, .. }) => {
|
||
krate.attrs = vec![];
|
||
krate.module = ast::Mod { inner: orig_mod_span, items: vec![], inline: true };
|
||
self.cx.span_err(
|
||
span,
|
||
&format!(
|
||
"expected crate top-level item to be a module after macro expansion, found {} {}",
|
||
kind.article(), kind.descr()
|
||
),
|
||
);
|
||
}
|
||
};
|
||
self.cx.trace_macros_diag();
|
||
krate
|
||
}
|
||
|
||
// Recursively expand all macro invocations in this AST fragment.
|
||
pub fn fully_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 undetermined_invocations = Vec::new();
|
||
let (mut progress, mut force) = (false, !self.monotonic);
|
||
loop {
|
||
let (invoc, res) = if let Some(invoc) = invocations.pop() {
|
||
invoc
|
||
} else {
|
||
self.resolve_imports();
|
||
if undetermined_invocations.is_empty() {
|
||
break;
|
||
}
|
||
invocations = mem::take(&mut undetermined_invocations);
|
||
force = !mem::replace(&mut progress, false);
|
||
continue;
|
||
};
|
||
|
||
let res = match res {
|
||
Some(res) => res,
|
||
None => {
|
||
let eager_expansion_root = if self.monotonic {
|
||
invoc.expansion_data.id
|
||
} else {
|
||
orig_expansion_data.id
|
||
};
|
||
match self.cx.resolver.resolve_macro_invocation(
|
||
&invoc,
|
||
eager_expansion_root,
|
||
force,
|
||
) {
|
||
Ok(res) => res,
|
||
Err(Indeterminate) => {
|
||
// Cannot resolve, will retry this invocation later.
|
||
undetermined_invocations.push((invoc, None));
|
||
continue;
|
||
}
|
||
}
|
||
}
|
||
};
|
||
|
||
let ExpansionData { depth, id: expn_id, .. } = invoc.expansion_data;
|
||
self.cx.current_expansion = invoc.expansion_data.clone();
|
||
|
||
// FIXME(jseyfried): Refactor out the following logic
|
||
let (expanded_fragment, new_invocations) = match res {
|
||
InvocationRes::Single(ext) => match self.expand_invoc(invoc, &ext.kind) {
|
||
ExpandResult::Ready(fragment) => self.collect_invocations(fragment, &[]),
|
||
ExpandResult::Retry(invoc, explanation) => {
|
||
if force {
|
||
// We are stuck, stop retrying and produce a dummy fragment.
|
||
let span = invoc.span();
|
||
self.cx.span_err(span, &explanation);
|
||
let fragment = invoc.fragment_kind.dummy(span);
|
||
self.collect_invocations(fragment, &[])
|
||
} else {
|
||
// Cannot expand, will retry this invocation later.
|
||
undetermined_invocations
|
||
.push((invoc, Some(InvocationRes::Single(ext))));
|
||
continue;
|
||
}
|
||
}
|
||
},
|
||
InvocationRes::DeriveContainer(_exts) => {
|
||
// FIXME: Consider using the derive resolutions (`_exts`) immediately,
|
||
// instead of enqueuing the derives to be resolved again later.
|
||
let (derives, item) = match invoc.kind {
|
||
InvocationKind::DeriveContainer { derives, item } => (derives, item),
|
||
_ => unreachable!(),
|
||
};
|
||
if !item.derive_allowed() {
|
||
self.error_derive_forbidden_on_non_adt(&derives, &item);
|
||
}
|
||
|
||
let mut item = self.fully_configure(item);
|
||
item.visit_attrs(|attrs| attrs.retain(|a| !a.has_name(sym::derive)));
|
||
|
||
let mut derive_placeholders = Vec::with_capacity(derives.len());
|
||
invocations.reserve(derives.len());
|
||
for path in derives {
|
||
let expn_id = ExpnId::fresh(None);
|
||
derive_placeholders.push(NodeId::placeholder_from_expn_id(expn_id));
|
||
invocations.push((
|
||
Invocation {
|
||
kind: InvocationKind::Derive { path, item: item.clone() },
|
||
fragment_kind: invoc.fragment_kind,
|
||
expansion_data: ExpansionData {
|
||
id: expn_id,
|
||
..invoc.expansion_data.clone()
|
||
},
|
||
},
|
||
None,
|
||
));
|
||
}
|
||
let fragment =
|
||
invoc.fragment_kind.expect_from_annotatables(::std::iter::once(item));
|
||
self.collect_invocations(fragment, &derive_placeholders)
|
||
}
|
||
};
|
||
|
||
progress = true;
|
||
if expanded_fragments.len() < depth {
|
||
expanded_fragments.push(Vec::new());
|
||
}
|
||
expanded_fragments[depth - 1].push((expn_id, expanded_fragment));
|
||
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 (expn_id, expanded_fragment) in expanded_fragments.into_iter().rev() {
|
||
placeholder_expander
|
||
.add(NodeId::placeholder_from_expn_id(expn_id), expanded_fragment);
|
||
}
|
||
}
|
||
fragment_with_placeholders.mut_visit_with(&mut placeholder_expander);
|
||
fragment_with_placeholders
|
||
}
|
||
|
||
fn error_derive_forbidden_on_non_adt(&self, derives: &[Path], item: &Annotatable) {
|
||
let attr = attr::find_by_name(item.attrs(), sym::derive);
|
||
let span = attr.map_or(item.span(), |attr| attr.span);
|
||
let mut err = self
|
||
.cx
|
||
.struct_span_err(span, "`derive` may only be applied to structs, enums and unions");
|
||
if let Some(ast::Attribute { style: ast::AttrStyle::Inner, .. }) = attr {
|
||
let trait_list = derives.iter().map(|t| pprust::path_to_string(t)).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();
|
||
}
|
||
|
||
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,
|
||
extra_placeholders: &[NodeId],
|
||
) -> (AstFragment, Vec<(Invocation, Option<InvocationRes>)>) {
|
||
// Resolve `$crate`s in the fragment for pretty-printing.
|
||
self.cx.resolver.resolve_dollar_crates();
|
||
|
||
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);
|
||
fragment.add_placeholders(extra_placeholders);
|
||
collector.invocations
|
||
};
|
||
|
||
if self.monotonic {
|
||
self.cx
|
||
.resolver
|
||
.visit_ast_fragment_with_placeholders(self.cx.current_expansion.id, &fragment);
|
||
}
|
||
|
||
(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(cfg.flat_map_trait_item(item).pop().unwrap())
|
||
}
|
||
Annotatable::ImplItem(item) => {
|
||
Annotatable::ImplItem(cfg.flat_map_impl_item(item).pop().unwrap())
|
||
}
|
||
Annotatable::ForeignItem(item) => {
|
||
Annotatable::ForeignItem(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
|
||
}),
|
||
Annotatable::Arm(arm) => Annotatable::Arm(cfg.flat_map_arm(arm).pop().unwrap()),
|
||
Annotatable::Field(field) => {
|
||
Annotatable::Field(cfg.flat_map_field(field).pop().unwrap())
|
||
}
|
||
Annotatable::FieldPat(fp) => {
|
||
Annotatable::FieldPat(cfg.flat_map_field_pattern(fp).pop().unwrap())
|
||
}
|
||
Annotatable::GenericParam(param) => {
|
||
Annotatable::GenericParam(cfg.flat_map_generic_param(param).pop().unwrap())
|
||
}
|
||
Annotatable::Param(param) => {
|
||
Annotatable::Param(cfg.flat_map_param(param).pop().unwrap())
|
||
}
|
||
Annotatable::StructField(sf) => {
|
||
Annotatable::StructField(cfg.flat_map_struct_field(sf).pop().unwrap())
|
||
}
|
||
Annotatable::Variant(v) => Annotatable::Variant(cfg.flat_map_variant(v).pop().unwrap()),
|
||
}
|
||
}
|
||
|
||
fn error_recursion_limit_reached(&mut self) {
|
||
let expn_data = self.cx.current_expansion.id.expn_data();
|
||
let suggested_limit = self.cx.ecfg.recursion_limit * 2;
|
||
self.cx
|
||
.struct_span_err(
|
||
expn_data.call_site,
|
||
&format!("recursion limit reached while expanding `{}`", expn_data.kind.descr()),
|
||
)
|
||
.help(&format!(
|
||
"consider adding a `#![recursion_limit=\"{}\"]` attribute to your crate (`{}`)",
|
||
suggested_limit, self.cx.ecfg.crate_name,
|
||
))
|
||
.emit();
|
||
self.cx.trace_macros_diag();
|
||
}
|
||
|
||
/// A macro's expansion does not fit in this fragment kind.
|
||
/// For example, a non-type macro in a type position.
|
||
fn error_wrong_fragment_kind(&mut self, kind: AstFragmentKind, mac: &ast::MacCall, span: Span) {
|
||
let msg = format!(
|
||
"non-{kind} macro in {kind} position: {path}",
|
||
kind = kind.name(),
|
||
path = pprust::path_to_string(&mac.path),
|
||
);
|
||
self.cx.span_err(span, &msg);
|
||
self.cx.trace_macros_diag();
|
||
}
|
||
|
||
fn expand_invoc(
|
||
&mut self,
|
||
invoc: Invocation,
|
||
ext: &SyntaxExtensionKind,
|
||
) -> ExpandResult<AstFragment, Invocation> {
|
||
let recursion_limit =
|
||
self.cx.reduced_recursion_limit.unwrap_or(self.cx.ecfg.recursion_limit);
|
||
if self.cx.current_expansion.depth > recursion_limit {
|
||
if self.cx.reduced_recursion_limit.is_none() {
|
||
self.error_recursion_limit_reached();
|
||
}
|
||
|
||
// Reduce the recursion limit by half each time it triggers.
|
||
self.cx.reduced_recursion_limit = Some(recursion_limit / 2);
|
||
|
||
return ExpandResult::Ready(invoc.fragment_kind.dummy(invoc.span()));
|
||
}
|
||
|
||
let (fragment_kind, span) = (invoc.fragment_kind, invoc.span());
|
||
ExpandResult::Ready(match invoc.kind {
|
||
InvocationKind::Bang { mac, .. } => match ext {
|
||
SyntaxExtensionKind::Bang(expander) => {
|
||
self.gate_proc_macro_expansion_kind(span, fragment_kind);
|
||
let tok_result = match expander.expand(self.cx, span, mac.args.inner_tokens()) {
|
||
Err(_) => return ExpandResult::Ready(fragment_kind.dummy(span)),
|
||
Ok(ts) => ts,
|
||
};
|
||
self.parse_ast_fragment(tok_result, fragment_kind, &mac.path, span)
|
||
}
|
||
SyntaxExtensionKind::LegacyBang(expander) => {
|
||
let prev = self.cx.current_expansion.prior_type_ascription;
|
||
self.cx.current_expansion.prior_type_ascription = mac.prior_type_ascription;
|
||
let tok_result = expander.expand(self.cx, span, mac.args.inner_tokens());
|
||
let result = if let Some(result) = fragment_kind.make_from(tok_result) {
|
||
result
|
||
} else {
|
||
self.error_wrong_fragment_kind(fragment_kind, &mac, span);
|
||
fragment_kind.dummy(span)
|
||
};
|
||
self.cx.current_expansion.prior_type_ascription = prev;
|
||
result
|
||
}
|
||
_ => unreachable!(),
|
||
},
|
||
InvocationKind::Attr { attr, mut item, derives, after_derive } => match ext {
|
||
SyntaxExtensionKind::Attr(expander) => {
|
||
self.gate_proc_macro_input(&item);
|
||
self.gate_proc_macro_attr_item(span, &item);
|
||
let tokens = item.into_tokens();
|
||
let attr_item = attr.unwrap_normal_item();
|
||
if let MacArgs::Eq(..) = attr_item.args {
|
||
self.cx.span_err(span, "key-value macro attributes are not supported");
|
||
}
|
||
let inner_tokens = attr_item.args.inner_tokens();
|
||
let tok_result = match expander.expand(self.cx, span, inner_tokens, tokens) {
|
||
Err(_) => return ExpandResult::Ready(fragment_kind.dummy(span)),
|
||
Ok(ts) => ts,
|
||
};
|
||
self.parse_ast_fragment(tok_result, fragment_kind, &attr_item.path, span)
|
||
}
|
||
SyntaxExtensionKind::LegacyAttr(expander) => {
|
||
match validate_attr::parse_meta(self.cx.parse_sess, &attr) {
|
||
Ok(meta) => {
|
||
let items = match expander.expand(self.cx, span, &meta, item) {
|
||
ExpandResult::Ready(items) => items,
|
||
ExpandResult::Retry(item, explanation) => {
|
||
// Reassemble the original invocation for retrying.
|
||
return ExpandResult::Retry(
|
||
Invocation {
|
||
kind: InvocationKind::Attr {
|
||
attr,
|
||
item,
|
||
derives,
|
||
after_derive,
|
||
},
|
||
..invoc
|
||
},
|
||
explanation,
|
||
);
|
||
}
|
||
};
|
||
fragment_kind.expect_from_annotatables(items)
|
||
}
|
||
Err(mut err) => {
|
||
err.emit();
|
||
fragment_kind.dummy(span)
|
||
}
|
||
}
|
||
}
|
||
SyntaxExtensionKind::NonMacroAttr { mark_used } => {
|
||
attr::mark_known(&attr);
|
||
if *mark_used {
|
||
attr::mark_used(&attr);
|
||
}
|
||
item.visit_attrs(|attrs| attrs.push(attr));
|
||
fragment_kind.expect_from_annotatables(iter::once(item))
|
||
}
|
||
_ => unreachable!(),
|
||
},
|
||
InvocationKind::Derive { path, item } => match ext {
|
||
SyntaxExtensionKind::Derive(expander)
|
||
| SyntaxExtensionKind::LegacyDerive(expander) => {
|
||
if !item.derive_allowed() {
|
||
return ExpandResult::Ready(fragment_kind.dummy(span));
|
||
}
|
||
if let SyntaxExtensionKind::Derive(..) = ext {
|
||
self.gate_proc_macro_input(&item);
|
||
}
|
||
let meta = ast::MetaItem { kind: ast::MetaItemKind::Word, span, path };
|
||
let items = match expander.expand(self.cx, span, &meta, item) {
|
||
ExpandResult::Ready(items) => items,
|
||
ExpandResult::Retry(item, explanation) => {
|
||
// Reassemble the original invocation for retrying.
|
||
return ExpandResult::Retry(
|
||
Invocation {
|
||
kind: InvocationKind::Derive { path: meta.path, item },
|
||
..invoc
|
||
},
|
||
explanation,
|
||
);
|
||
}
|
||
};
|
||
fragment_kind.expect_from_annotatables(items)
|
||
}
|
||
_ => unreachable!(),
|
||
},
|
||
InvocationKind::DeriveContainer { .. } => unreachable!(),
|
||
})
|
||
}
|
||
|
||
fn gate_proc_macro_attr_item(&self, span: Span, item: &Annotatable) {
|
||
let kind = match item {
|
||
Annotatable::Item(_)
|
||
| Annotatable::TraitItem(_)
|
||
| Annotatable::ImplItem(_)
|
||
| Annotatable::ForeignItem(_) => return,
|
||
Annotatable::Stmt(_) => "statements",
|
||
Annotatable::Expr(_) => "expressions",
|
||
Annotatable::Arm(..)
|
||
| Annotatable::Field(..)
|
||
| Annotatable::FieldPat(..)
|
||
| Annotatable::GenericParam(..)
|
||
| Annotatable::Param(..)
|
||
| Annotatable::StructField(..)
|
||
| Annotatable::Variant(..) => panic!("unexpected annotatable"),
|
||
};
|
||
if self.cx.ecfg.proc_macro_hygiene() {
|
||
return;
|
||
}
|
||
feature_err(
|
||
self.cx.parse_sess,
|
||
sym::proc_macro_hygiene,
|
||
span,
|
||
&format!("custom attributes cannot be applied to {}", kind),
|
||
)
|
||
.emit();
|
||
}
|
||
|
||
fn gate_proc_macro_input(&self, annotatable: &Annotatable) {
|
||
struct GateProcMacroInput<'a> {
|
||
parse_sess: &'a ParseSess,
|
||
}
|
||
|
||
impl<'ast, 'a> Visitor<'ast> for GateProcMacroInput<'a> {
|
||
fn visit_item(&mut self, item: &'ast ast::Item) {
|
||
match &item.kind {
|
||
ast::ItemKind::Mod(module) if !module.inline => {
|
||
feature_err(
|
||
self.parse_sess,
|
||
sym::proc_macro_hygiene,
|
||
item.span,
|
||
"non-inline modules in proc macro input are unstable",
|
||
)
|
||
.emit();
|
||
}
|
||
_ => {}
|
||
}
|
||
|
||
visit::walk_item(self, item);
|
||
}
|
||
|
||
fn visit_mac(&mut self, _: &'ast ast::MacCall) {}
|
||
}
|
||
|
||
if !self.cx.ecfg.proc_macro_hygiene() {
|
||
annotatable.visit_with(&mut GateProcMacroInput { parse_sess: self.cx.parse_sess });
|
||
}
|
||
}
|
||
|
||
fn gate_proc_macro_expansion_kind(&self, span: Span, kind: AstFragmentKind) {
|
||
let kind = match kind {
|
||
AstFragmentKind::Expr | AstFragmentKind::OptExpr => "expressions",
|
||
AstFragmentKind::Pat => "patterns",
|
||
AstFragmentKind::Stmts => "statements",
|
||
AstFragmentKind::Ty
|
||
| AstFragmentKind::Items
|
||
| AstFragmentKind::TraitItems
|
||
| AstFragmentKind::ImplItems
|
||
| AstFragmentKind::ForeignItems => return,
|
||
AstFragmentKind::Arms
|
||
| AstFragmentKind::Fields
|
||
| AstFragmentKind::FieldPats
|
||
| AstFragmentKind::GenericParams
|
||
| AstFragmentKind::Params
|
||
| AstFragmentKind::StructFields
|
||
| AstFragmentKind::Variants => panic!("unexpected AST fragment kind"),
|
||
};
|
||
if self.cx.ecfg.proc_macro_hygiene() {
|
||
return;
|
||
}
|
||
feature_err(
|
||
self.cx.parse_sess,
|
||
sym::proc_macro_hygiene,
|
||
span,
|
||
&format!("procedural macros cannot be expanded to {}", kind),
|
||
)
|
||
.emit();
|
||
}
|
||
|
||
fn parse_ast_fragment(
|
||
&mut self,
|
||
toks: TokenStream,
|
||
kind: AstFragmentKind,
|
||
path: &Path,
|
||
span: Span,
|
||
) -> AstFragment {
|
||
let mut parser = self.cx.new_parser_from_tts(toks);
|
||
match parse_ast_fragment(&mut parser, kind) {
|
||
Ok(fragment) => {
|
||
ensure_complete_parse(&mut parser, path, kind.name(), span);
|
||
fragment
|
||
}
|
||
Err(mut err) => {
|
||
err.set_span(span);
|
||
annotate_err_with_kind(&mut err, kind, span);
|
||
err.emit();
|
||
self.cx.trace_macros_diag();
|
||
kind.dummy(span)
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
pub fn parse_ast_fragment<'a>(
|
||
this: &mut Parser<'a>,
|
||
kind: AstFragmentKind,
|
||
) -> PResult<'a, AstFragment> {
|
||
Ok(match kind {
|
||
AstFragmentKind::Items => {
|
||
let mut items = SmallVec::new();
|
||
while let Some(item) = this.parse_item()? {
|
||
items.push(item);
|
||
}
|
||
AstFragment::Items(items)
|
||
}
|
||
AstFragmentKind::TraitItems => {
|
||
let mut items = SmallVec::new();
|
||
while let Some(item) = this.parse_trait_item()? {
|
||
items.extend(item);
|
||
}
|
||
AstFragment::TraitItems(items)
|
||
}
|
||
AstFragmentKind::ImplItems => {
|
||
let mut items = SmallVec::new();
|
||
while let Some(item) = this.parse_impl_item()? {
|
||
items.extend(item);
|
||
}
|
||
AstFragment::ImplItems(items)
|
||
}
|
||
AstFragmentKind::ForeignItems => {
|
||
let mut items = SmallVec::new();
|
||
while let Some(item) = this.parse_foreign_item()? {
|
||
items.extend(item);
|
||
}
|
||
AstFragment::ForeignItems(items)
|
||
}
|
||
AstFragmentKind::Stmts => {
|
||
let mut stmts = SmallVec::new();
|
||
// Won't make progress on a `}`.
|
||
while this.token != token::Eof && this.token != token::CloseDelim(token::Brace) {
|
||
if let Some(stmt) = this.parse_full_stmt()? {
|
||
stmts.push(stmt);
|
||
}
|
||
}
|
||
AstFragment::Stmts(stmts)
|
||
}
|
||
AstFragmentKind::Expr => AstFragment::Expr(this.parse_expr()?),
|
||
AstFragmentKind::OptExpr => {
|
||
if this.token != token::Eof {
|
||
AstFragment::OptExpr(Some(this.parse_expr()?))
|
||
} else {
|
||
AstFragment::OptExpr(None)
|
||
}
|
||
}
|
||
AstFragmentKind::Ty => AstFragment::Ty(this.parse_ty()?),
|
||
AstFragmentKind::Pat => AstFragment::Pat(this.parse_pat(None)?),
|
||
AstFragmentKind::Arms
|
||
| AstFragmentKind::Fields
|
||
| AstFragmentKind::FieldPats
|
||
| AstFragmentKind::GenericParams
|
||
| AstFragmentKind::Params
|
||
| AstFragmentKind::StructFields
|
||
| AstFragmentKind::Variants => panic!("unexpected AST fragment kind"),
|
||
})
|
||
}
|
||
|
||
pub fn ensure_complete_parse<'a>(
|
||
this: &mut Parser<'a>,
|
||
macro_path: &Path,
|
||
kind_name: &str,
|
||
span: Span,
|
||
) {
|
||
if this.token != token::Eof {
|
||
let token = pprust::token_to_string(&this.token);
|
||
let msg = format!("macro expansion ignores token `{}` and any following", token);
|
||
// Avoid emitting backtrace info twice.
|
||
let def_site_span = this.token.span.with_ctxt(SyntaxContext::root());
|
||
let mut err = this.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",
|
||
pprust::path_to_string(macro_path),
|
||
kind_name,
|
||
);
|
||
err.note(&msg);
|
||
let semi_span = this.sess.source_map().next_point(span);
|
||
|
||
let semi_full_span = semi_span.to(this.sess.source_map().next_point(semi_span));
|
||
match this.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, Option<InvocationRes>)>,
|
||
monotonic: bool,
|
||
}
|
||
|
||
impl<'a, 'b> InvocationCollector<'a, 'b> {
|
||
fn collect(&mut self, fragment_kind: AstFragmentKind, kind: InvocationKind) -> AstFragment {
|
||
// Expansion data for all the collected invocations is set upon their resolution,
|
||
// with exception of the derive container case which is not resolved and can get
|
||
// its expansion data immediately.
|
||
let expn_data = match &kind {
|
||
InvocationKind::DeriveContainer { item, .. } => Some(ExpnData {
|
||
parent: self.cx.current_expansion.id,
|
||
..ExpnData::default(
|
||
ExpnKind::Macro(MacroKind::Attr, sym::derive),
|
||
item.span(),
|
||
self.cx.parse_sess.edition,
|
||
)
|
||
}),
|
||
_ => None,
|
||
};
|
||
let expn_id = ExpnId::fresh(expn_data);
|
||
let vis = kind.placeholder_visibility();
|
||
self.invocations.push((
|
||
Invocation {
|
||
kind,
|
||
fragment_kind,
|
||
expansion_data: ExpansionData {
|
||
id: expn_id,
|
||
depth: self.cx.current_expansion.depth + 1,
|
||
..self.cx.current_expansion.clone()
|
||
},
|
||
},
|
||
None,
|
||
));
|
||
placeholder(fragment_kind, NodeId::placeholder_from_expn_id(expn_id), vis)
|
||
}
|
||
|
||
fn collect_bang(
|
||
&mut self,
|
||
mac: ast::MacCall,
|
||
span: Span,
|
||
kind: AstFragmentKind,
|
||
) -> AstFragment {
|
||
self.collect(kind, InvocationKind::Bang { mac, span })
|
||
}
|
||
|
||
fn collect_attr(
|
||
&mut self,
|
||
attr: Option<ast::Attribute>,
|
||
derives: Vec<Path>,
|
||
item: Annotatable,
|
||
kind: AstFragmentKind,
|
||
after_derive: bool,
|
||
) -> AstFragment {
|
||
self.collect(
|
||
kind,
|
||
match attr {
|
||
Some(attr) => InvocationKind::Attr { attr, item, derives, after_derive },
|
||
None => InvocationKind::DeriveContainer { derives, item },
|
||
},
|
||
)
|
||
}
|
||
|
||
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.has_name(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.custom_inner_attributes()
|
||
&& attr.style == ast::AttrStyle::Inner
|
||
&& !attr.has_name(sym::test)
|
||
{
|
||
feature_err(
|
||
&self.cx.parse_sess,
|
||
sym::custom_inner_attributes,
|
||
attr.span,
|
||
"non-builtin inner attributes are unstable",
|
||
)
|
||
.emit();
|
||
}
|
||
}
|
||
attr
|
||
}
|
||
|
||
/// If `item` is an attr invocation, remove and return the macro attribute and derive traits.
|
||
fn classify_item(
|
||
&mut self,
|
||
item: &mut impl HasAttrs,
|
||
) -> (Option<ast::Attribute>, Vec<Path>, /* after_derive */ bool) {
|
||
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(
|
||
&mut self,
|
||
nonitem: &mut impl HasAttrs,
|
||
) -> (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() {
|
||
rustc_ast_passes::feature_gate::check_attribute(attr, self.cx.parse_sess, features);
|
||
validate_attr::check_meta(self.cx.parse_sess, attr);
|
||
|
||
// macros are expanded before any lint passes so this warning has to be hardcoded
|
||
if attr.has_name(sym::derive) {
|
||
self.cx
|
||
.parse_sess()
|
||
.span_diagnostic
|
||
.struct_span_warn(attr.span, "`#[derive]` does nothing on macro invocations")
|
||
.note("this may become a hard error in a future release")
|
||
.emit();
|
||
}
|
||
|
||
if attr.doc_str().is_some() {
|
||
self.cx.parse_sess.buffer_lint_with_diagnostic(
|
||
&UNUSED_DOC_COMMENTS,
|
||
attr.span,
|
||
ast::CRATE_NODE_ID,
|
||
"unused doc comment",
|
||
BuiltinLintDiagnostics::UnusedDocComment(attr.span),
|
||
);
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
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.kind);
|
||
|
||
// ignore derives so they remain unused
|
||
let (attr, after_derive) = self.classify_nonitem(&mut expr);
|
||
|
||
if let Some(ref attr_value) = attr {
|
||
// Collect the invoc regardless of whether or not attributes are permitted here
|
||
// expansion will eat the attribute so it won't error later.
|
||
self.cfg.maybe_emit_expr_attr_err(attr_value);
|
||
|
||
// 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::MacCall(mac) = expr.kind {
|
||
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 flat_map_arm(&mut self, arm: ast::Arm) -> SmallVec<[ast::Arm; 1]> {
|
||
let mut arm = configure!(self, arm);
|
||
|
||
let (attr, traits, after_derive) = self.classify_item(&mut arm);
|
||
if attr.is_some() || !traits.is_empty() {
|
||
return self
|
||
.collect_attr(
|
||
attr,
|
||
traits,
|
||
Annotatable::Arm(arm),
|
||
AstFragmentKind::Arms,
|
||
after_derive,
|
||
)
|
||
.make_arms();
|
||
}
|
||
|
||
noop_flat_map_arm(arm, self)
|
||
}
|
||
|
||
fn flat_map_field(&mut self, field: ast::Field) -> SmallVec<[ast::Field; 1]> {
|
||
let mut field = configure!(self, field);
|
||
|
||
let (attr, traits, after_derive) = self.classify_item(&mut field);
|
||
if attr.is_some() || !traits.is_empty() {
|
||
return self
|
||
.collect_attr(
|
||
attr,
|
||
traits,
|
||
Annotatable::Field(field),
|
||
AstFragmentKind::Fields,
|
||
after_derive,
|
||
)
|
||
.make_fields();
|
||
}
|
||
|
||
noop_flat_map_field(field, self)
|
||
}
|
||
|
||
fn flat_map_field_pattern(&mut self, fp: ast::FieldPat) -> SmallVec<[ast::FieldPat; 1]> {
|
||
let mut fp = configure!(self, fp);
|
||
|
||
let (attr, traits, after_derive) = self.classify_item(&mut fp);
|
||
if attr.is_some() || !traits.is_empty() {
|
||
return self
|
||
.collect_attr(
|
||
attr,
|
||
traits,
|
||
Annotatable::FieldPat(fp),
|
||
AstFragmentKind::FieldPats,
|
||
after_derive,
|
||
)
|
||
.make_field_patterns();
|
||
}
|
||
|
||
noop_flat_map_field_pattern(fp, self)
|
||
}
|
||
|
||
fn flat_map_param(&mut self, p: ast::Param) -> SmallVec<[ast::Param; 1]> {
|
||
let mut p = configure!(self, p);
|
||
|
||
let (attr, traits, after_derive) = self.classify_item(&mut p);
|
||
if attr.is_some() || !traits.is_empty() {
|
||
return self
|
||
.collect_attr(
|
||
attr,
|
||
traits,
|
||
Annotatable::Param(p),
|
||
AstFragmentKind::Params,
|
||
after_derive,
|
||
)
|
||
.make_params();
|
||
}
|
||
|
||
noop_flat_map_param(p, self)
|
||
}
|
||
|
||
fn flat_map_struct_field(&mut self, sf: ast::StructField) -> SmallVec<[ast::StructField; 1]> {
|
||
let mut sf = configure!(self, sf);
|
||
|
||
let (attr, traits, after_derive) = self.classify_item(&mut sf);
|
||
if attr.is_some() || !traits.is_empty() {
|
||
return self
|
||
.collect_attr(
|
||
attr,
|
||
traits,
|
||
Annotatable::StructField(sf),
|
||
AstFragmentKind::StructFields,
|
||
after_derive,
|
||
)
|
||
.make_struct_fields();
|
||
}
|
||
|
||
noop_flat_map_struct_field(sf, self)
|
||
}
|
||
|
||
fn flat_map_variant(&mut self, variant: ast::Variant) -> SmallVec<[ast::Variant; 1]> {
|
||
let mut variant = configure!(self, variant);
|
||
|
||
let (attr, traits, after_derive) = self.classify_item(&mut variant);
|
||
if attr.is_some() || !traits.is_empty() {
|
||
return self
|
||
.collect_attr(
|
||
attr,
|
||
traits,
|
||
Annotatable::Variant(variant),
|
||
AstFragmentKind::Variants,
|
||
after_derive,
|
||
)
|
||
.make_variants();
|
||
}
|
||
|
||
noop_flat_map_variant(variant, self)
|
||
}
|
||
|
||
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.kind);
|
||
|
||
// Ignore derives so they remain unused.
|
||
let (attr, after_derive) = self.classify_nonitem(&mut expr);
|
||
|
||
if let Some(ref attr_value) = attr {
|
||
self.cfg.maybe_emit_expr_attr_err(attr_value);
|
||
|
||
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::MacCall(mac) = expr.kind {
|
||
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.kind {
|
||
PatKind::MacCall(_) => {}
|
||
_ => return noop_visit_pat(pat, self),
|
||
}
|
||
|
||
visit_clobber(pat, |mut pat| match mem::replace(&mut pat.kind, PatKind::Wild) {
|
||
PatKind::MacCall(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::MacCall(mac) = stmt.kind {
|
||
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, kind, span } = stmt;
|
||
noop_flat_map_stmt_kind(kind, self)
|
||
.into_iter()
|
||
.map(|kind| ast::Stmt { id, kind, 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();
|
||
}
|
||
|
||
let mut attrs = mem::take(&mut item.attrs); // We do this to please borrowck.
|
||
let ident = item.ident;
|
||
let span = item.span;
|
||
|
||
match item.kind {
|
||
ast::ItemKind::MacCall(..) => {
|
||
item.attrs = attrs;
|
||
self.check_attributes(&item.attrs);
|
||
item.and_then(|item| match item.kind {
|
||
ItemKind::MacCall(mac) => self
|
||
.collect(AstFragmentKind::Items, InvocationKind::Bang { mac, span })
|
||
.make_items(),
|
||
_ => unreachable!(),
|
||
})
|
||
}
|
||
ast::ItemKind::Mod(ref mut old_mod @ ast::Mod { .. }) if ident != Ident::invalid() => {
|
||
let sess = self.cx.parse_sess;
|
||
let orig_ownership = self.cx.current_expansion.directory_ownership;
|
||
let mut module = (*self.cx.current_expansion.module).clone();
|
||
|
||
let pushed = &mut false; // Record `parse_external_mod` pushing so we can pop.
|
||
let dir = Directory { ownership: orig_ownership, path: module.directory };
|
||
let Directory { ownership, path } = if old_mod.inline {
|
||
// Inline `mod foo { ... }`, but we still need to push directories.
|
||
item.attrs = attrs;
|
||
push_directory(ident, &item.attrs, dir)
|
||
} else {
|
||
// We have an outline `mod foo;` so we need to parse the file.
|
||
let (new_mod, dir) =
|
||
parse_external_mod(sess, ident, span, dir, &mut attrs, pushed);
|
||
|
||
let krate = ast::Crate {
|
||
span: new_mod.inner,
|
||
module: new_mod,
|
||
attrs,
|
||
proc_macros: vec![],
|
||
};
|
||
if let Some(extern_mod_loaded) = self.cx.extern_mod_loaded {
|
||
extern_mod_loaded(&krate);
|
||
}
|
||
|
||
*old_mod = krate.module;
|
||
item.attrs = krate.attrs;
|
||
// File can have inline attributes, e.g., `#![cfg(...)]` & co. => Reconfigure.
|
||
item = match self.configure(item) {
|
||
Some(node) => node,
|
||
None => {
|
||
if *pushed {
|
||
sess.included_mod_stack.borrow_mut().pop();
|
||
}
|
||
return Default::default();
|
||
}
|
||
};
|
||
dir
|
||
};
|
||
|
||
// Set the module info before we flat map.
|
||
self.cx.current_expansion.directory_ownership = ownership;
|
||
module.directory = path;
|
||
module.mod_path.push(ident);
|
||
let orig_module =
|
||
mem::replace(&mut self.cx.current_expansion.module, Rc::new(module));
|
||
|
||
let result = noop_flat_map_item(item, self);
|
||
|
||
// Restore the module info.
|
||
self.cx.current_expansion.module = orig_module;
|
||
self.cx.current_expansion.directory_ownership = orig_ownership;
|
||
if *pushed {
|
||
sess.included_mod_stack.borrow_mut().pop();
|
||
}
|
||
result
|
||
}
|
||
_ => {
|
||
item.attrs = attrs;
|
||
noop_flat_map_item(item, self)
|
||
}
|
||
}
|
||
}
|
||
|
||
fn flat_map_trait_item(&mut self, item: P<ast::AssocItem>) -> SmallVec<[P<ast::AssocItem>; 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(item),
|
||
AstFragmentKind::TraitItems,
|
||
after_derive,
|
||
)
|
||
.make_trait_items();
|
||
}
|
||
|
||
match item.kind {
|
||
ast::AssocItemKind::MacCall(..) => {
|
||
self.check_attributes(&item.attrs);
|
||
item.and_then(|item| match item.kind {
|
||
ast::AssocItemKind::MacCall(mac) => self
|
||
.collect_bang(mac, item.span, AstFragmentKind::TraitItems)
|
||
.make_trait_items(),
|
||
_ => unreachable!(),
|
||
})
|
||
}
|
||
_ => noop_flat_map_assoc_item(item, self),
|
||
}
|
||
}
|
||
|
||
fn flat_map_impl_item(&mut self, item: P<ast::AssocItem>) -> SmallVec<[P<ast::AssocItem>; 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(item),
|
||
AstFragmentKind::ImplItems,
|
||
after_derive,
|
||
)
|
||
.make_impl_items();
|
||
}
|
||
|
||
match item.kind {
|
||
ast::AssocItemKind::MacCall(..) => {
|
||
self.check_attributes(&item.attrs);
|
||
item.and_then(|item| match item.kind {
|
||
ast::AssocItemKind::MacCall(mac) => self
|
||
.collect_bang(mac, item.span, AstFragmentKind::ImplItems)
|
||
.make_impl_items(),
|
||
_ => unreachable!(),
|
||
})
|
||
}
|
||
_ => noop_flat_map_assoc_item(item, self),
|
||
}
|
||
}
|
||
|
||
fn visit_ty(&mut self, ty: &mut P<ast::Ty>) {
|
||
match ty.kind {
|
||
ast::TyKind::MacCall(_) => {}
|
||
_ => return noop_visit_ty(ty, self),
|
||
};
|
||
|
||
visit_clobber(ty, |mut ty| match mem::replace(&mut ty.kind, ast::TyKind::Err) {
|
||
ast::TyKind::MacCall(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: P<ast::ForeignItem>,
|
||
) -> SmallVec<[P<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(foreign_item),
|
||
AstFragmentKind::ForeignItems,
|
||
after_derive,
|
||
)
|
||
.make_foreign_items();
|
||
}
|
||
|
||
match foreign_item.kind {
|
||
ast::ForeignItemKind::MacCall(..) => {
|
||
self.check_attributes(&foreign_item.attrs);
|
||
foreign_item.and_then(|item| match item.kind {
|
||
ast::ForeignItemKind::MacCall(mac) => self
|
||
.collect_bang(mac, item.span, AstFragmentKind::ForeignItems)
|
||
.make_foreign_items(),
|
||
_ => unreachable!(),
|
||
})
|
||
}
|
||
_ => 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 flat_map_generic_param(
|
||
&mut self,
|
||
param: ast::GenericParam,
|
||
) -> SmallVec<[ast::GenericParam; 1]> {
|
||
let mut param = configure!(self, param);
|
||
|
||
let (attr, traits, after_derive) = self.classify_item(&mut param);
|
||
if attr.is_some() || !traits.is_empty() {
|
||
return self
|
||
.collect_attr(
|
||
attr,
|
||
traits,
|
||
Annotatable::GenericParam(param),
|
||
AstFragmentKind::GenericParams,
|
||
after_derive,
|
||
)
|
||
.make_generic_params();
|
||
}
|
||
|
||
noop_flat_map_generic_param(param, 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_attributes(slice::from_ref(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 = match self.cx.resolve_path(&*file.as_str(), it.span()) {
|
||
Ok(filename) => filename,
|
||
Err(mut err) => {
|
||
err.emit();
|
||
continue;
|
||
}
|
||
};
|
||
|
||
match self.cx.source_map().load_file(&filename) {
|
||
Ok(source_file) => {
|
||
let src = source_file
|
||
.src
|
||
.as_ref()
|
||
.expect("freshly loaded file should have a source");
|
||
let src_interned = Symbol::intern(src.as_str());
|
||
|
||
let include_info = vec![
|
||
ast::NestedMetaItem::MetaItem(attr::mk_name_value_item_str(
|
||
Ident::with_dummy_span(sym::file),
|
||
file,
|
||
DUMMY_SP,
|
||
)),
|
||
ast::NestedMetaItem::MetaItem(attr::mk_name_value_item_str(
|
||
Ident::with_dummy_span(sym::contents),
|
||
src_interned,
|
||
DUMMY_SP,
|
||
)),
|
||
];
|
||
|
||
let include_ident = Ident::with_dummy_span(sym::include);
|
||
let item = attr::mk_list_item(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");
|
||
|
||
err.emit();
|
||
}
|
||
}
|
||
}
|
||
} else {
|
||
let mut err = self
|
||
.cx
|
||
.struct_span_err(it.span(), "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.kind)
|
||
} 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(Ident::with_dummy_span(sym::doc), items);
|
||
*at = ast::Attribute {
|
||
kind: ast::AttrKind::Normal(AttrItem {
|
||
path: meta.path,
|
||
args: meta.kind.mac_args(meta.span),
|
||
}),
|
||
span: at.span,
|
||
id: at.id,
|
||
style: at.style,
|
||
};
|
||
} 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 keep_macs: bool,
|
||
}
|
||
|
||
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,
|
||
keep_macs: false,
|
||
}
|
||
}
|
||
|
||
fn proc_macro_hygiene(&self) -> bool {
|
||
self.features.map_or(false, |features| features.proc_macro_hygiene)
|
||
}
|
||
fn custom_inner_attributes(&self) -> bool {
|
||
self.features.map_or(false, |features| features.custom_inner_attributes)
|
||
}
|
||
}
|