687 lines
29 KiB
Rust
687 lines
29 KiB
Rust
use super::attr::InnerAttrForbiddenReason;
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use super::diagnostics::AttemptLocalParseRecovery;
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use super::expr::LhsExpr;
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use super::pat::RecoverComma;
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use super::path::PathStyle;
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use super::TrailingToken;
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use super::{
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AttrWrapper, BlockMode, FnParseMode, ForceCollect, Parser, Restrictions, SemiColonMode,
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};
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use crate::errors::{
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AssignmentElseNotAllowed, CompoundAssignmentExpressionInLet, ConstLetMutuallyExclusive,
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DocCommentDoesNotDocumentAnything, ExpectedStatementAfterOuterAttr, InvalidCurlyInLetElse,
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InvalidExpressionInLetElse, InvalidIdentiferStartsWithNumber, InvalidVariableDeclaration,
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InvalidVariableDeclarationSub, WrapExpressionInParentheses,
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};
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use crate::maybe_whole;
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use rustc_ast as ast;
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use rustc_ast::ptr::P;
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use rustc_ast::token::{self, Delimiter, TokenKind};
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use rustc_ast::util::classify;
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use rustc_ast::{AttrStyle, AttrVec, LocalKind, MacCall, MacCallStmt, MacStmtStyle};
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use rustc_ast::{Block, BlockCheckMode, Expr, ExprKind, HasAttrs, Local, Stmt};
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use rustc_ast::{StmtKind, DUMMY_NODE_ID};
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use rustc_errors::{Applicability, DiagnosticBuilder, ErrorGuaranteed, PResult};
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use rustc_span::source_map::{BytePos, Span};
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use rustc_span::symbol::{kw, sym};
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use std::mem;
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impl<'a> Parser<'a> {
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/// Parses a statement. This stops just before trailing semicolons on everything but items.
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/// e.g., a `StmtKind::Semi` parses to a `StmtKind::Expr`, leaving the trailing `;` unconsumed.
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// Public for rustfmt usage.
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pub fn parse_stmt(&mut self, force_collect: ForceCollect) -> PResult<'a, Option<Stmt>> {
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Ok(self.parse_stmt_without_recovery(false, force_collect).unwrap_or_else(|mut e| {
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e.emit();
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self.recover_stmt_(SemiColonMode::Break, BlockMode::Ignore);
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None
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}))
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}
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/// If `force_collect` is [`ForceCollect::Yes`], forces collection of tokens regardless of whether
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/// or not we have attributes
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pub(crate) fn parse_stmt_without_recovery(
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&mut self,
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capture_semi: bool,
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force_collect: ForceCollect,
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) -> PResult<'a, Option<Stmt>> {
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let attrs = self.parse_outer_attributes()?;
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let lo = self.token.span;
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// Don't use `maybe_whole` so that we have precise control
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// over when we bump the parser
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if let token::Interpolated(nt) = &self.token.kind && let token::NtStmt(stmt) = &**nt {
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let mut stmt = stmt.clone();
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self.bump();
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stmt.visit_attrs(|stmt_attrs| {
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attrs.prepend_to_nt_inner(stmt_attrs);
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});
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return Ok(Some(stmt.into_inner()));
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}
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if self.token.is_keyword(kw::Mut) && self.is_keyword_ahead(1, &[kw::Let]) {
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self.bump();
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let mut_let_span = lo.to(self.token.span);
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self.sess.emit_err(InvalidVariableDeclaration {
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span: mut_let_span,
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sub: InvalidVariableDeclarationSub::SwitchMutLetOrder(mut_let_span),
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});
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}
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Ok(Some(if self.token.is_keyword(kw::Let) {
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self.parse_local_mk(lo, attrs, capture_semi, force_collect)?
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} else if self.is_kw_followed_by_ident(kw::Mut) && self.may_recover() {
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self.recover_stmt_local_after_let(lo, attrs, InvalidVariableDeclarationSub::MissingLet)?
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} else if self.is_kw_followed_by_ident(kw::Auto) && self.may_recover() {
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self.bump(); // `auto`
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self.recover_stmt_local_after_let(
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lo,
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attrs,
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InvalidVariableDeclarationSub::UseLetNotAuto,
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)?
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} else if self.is_kw_followed_by_ident(sym::var) && self.may_recover() {
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self.bump(); // `var`
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self.recover_stmt_local_after_let(
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lo,
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attrs,
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InvalidVariableDeclarationSub::UseLetNotVar,
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)?
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} else if self.check_path() && !self.token.is_qpath_start() && !self.is_path_start_item() {
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// We have avoided contextual keywords like `union`, items with `crate` visibility,
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// or `auto trait` items. We aim to parse an arbitrary path `a::b` but not something
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// that starts like a path (1 token), but it fact not a path.
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// Also, we avoid stealing syntax from `parse_item_`.
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if force_collect == ForceCollect::Yes {
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self.collect_tokens_no_attrs(|this| this.parse_stmt_path_start(lo, attrs))
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} else {
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self.parse_stmt_path_start(lo, attrs)
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}?
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} else if let Some(item) = self.parse_item_common(
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attrs.clone(),
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false,
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true,
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FnParseMode { req_name: |_| true, req_body: true },
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force_collect,
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)? {
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// FIXME: Bad copy of attrs
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self.mk_stmt(lo.to(item.span), StmtKind::Item(P(item)))
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} else if self.eat(&token::Semi) {
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// Do not attempt to parse an expression if we're done here.
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self.error_outer_attrs(attrs);
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self.mk_stmt(lo, StmtKind::Empty)
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} else if self.token != token::CloseDelim(Delimiter::Brace) {
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// Remainder are line-expr stmts.
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let e = if force_collect == ForceCollect::Yes {
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self.collect_tokens_no_attrs(|this| {
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this.parse_expr_res(Restrictions::STMT_EXPR, Some(attrs))
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})
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} else {
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self.parse_expr_res(Restrictions::STMT_EXPR, Some(attrs))
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}?;
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if matches!(e.kind, ExprKind::Assign(..)) && self.eat_keyword(kw::Else) {
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let bl = self.parse_block()?;
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// Destructuring assignment ... else.
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// This is not allowed, but point it out in a nice way.
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self.sess.emit_err(AssignmentElseNotAllowed { span: e.span.to(bl.span) });
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}
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self.mk_stmt(lo.to(e.span), StmtKind::Expr(e))
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} else {
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self.error_outer_attrs(attrs);
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return Ok(None);
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}))
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}
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fn parse_stmt_path_start(&mut self, lo: Span, attrs: AttrWrapper) -> PResult<'a, Stmt> {
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let stmt = self.collect_tokens_trailing_token(attrs, ForceCollect::No, |this, attrs| {
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let path = this.parse_path(PathStyle::Expr)?;
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if this.eat(&token::Not) {
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let stmt_mac = this.parse_stmt_mac(lo, attrs, path)?;
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if this.token == token::Semi {
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return Ok((stmt_mac, TrailingToken::Semi));
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} else {
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return Ok((stmt_mac, TrailingToken::None));
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}
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}
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let expr = if this.eat(&token::OpenDelim(Delimiter::Brace)) {
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this.parse_struct_expr(None, path, true)?
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} else {
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let hi = this.prev_token.span;
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this.mk_expr(lo.to(hi), ExprKind::Path(None, path))
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};
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let expr = this.with_res(Restrictions::STMT_EXPR, |this| {
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this.parse_dot_or_call_expr_with(expr, lo, attrs)
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})?;
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// `DUMMY_SP` will get overwritten later in this function
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Ok((this.mk_stmt(rustc_span::DUMMY_SP, StmtKind::Expr(expr)), TrailingToken::None))
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})?;
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if let StmtKind::Expr(expr) = stmt.kind {
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// Perform this outside of the `collect_tokens_trailing_token` closure,
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// since our outer attributes do not apply to this part of the expression
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let expr = self.with_res(Restrictions::STMT_EXPR, |this| {
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this.parse_assoc_expr_with(
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0,
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LhsExpr::AlreadyParsed { expr, starts_statement: true },
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)
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})?;
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Ok(self.mk_stmt(lo.to(self.prev_token.span), StmtKind::Expr(expr)))
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} else {
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Ok(stmt)
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}
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}
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/// Parses a statement macro `mac!(args)` provided a `path` representing `mac`.
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/// At this point, the `!` token after the path has already been eaten.
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fn parse_stmt_mac(&mut self, lo: Span, attrs: AttrVec, path: ast::Path) -> PResult<'a, Stmt> {
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let args = self.parse_delim_args()?;
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let delim = args.delim.to_token();
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let hi = self.prev_token.span;
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let style = match delim {
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Delimiter::Brace => MacStmtStyle::Braces,
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_ => MacStmtStyle::NoBraces,
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};
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let mac = P(MacCall { path, args, prior_type_ascription: self.last_type_ascription });
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let kind = if (style == MacStmtStyle::Braces
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&& self.token != token::Dot
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&& self.token != token::Question)
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|| self.token == token::Semi
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|| self.token == token::Eof
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{
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StmtKind::MacCall(P(MacCallStmt { mac, style, attrs, tokens: None }))
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} else {
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// Since none of the above applied, this is an expression statement macro.
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let e = self.mk_expr(lo.to(hi), ExprKind::MacCall(mac));
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let e = self.maybe_recover_from_bad_qpath(e)?;
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let e = self.parse_dot_or_call_expr_with(e, lo, attrs)?;
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let e = self.parse_assoc_expr_with(
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0,
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LhsExpr::AlreadyParsed { expr: e, starts_statement: false },
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)?;
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StmtKind::Expr(e)
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};
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Ok(self.mk_stmt(lo.to(hi), kind))
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}
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/// Error on outer attributes in this context.
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/// Also error if the previous token was a doc comment.
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fn error_outer_attrs(&self, attrs: AttrWrapper) {
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if !attrs.is_empty()
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&& let attrs = attrs.take_for_recovery(self.sess)
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&& let attrs @ [.., last] = &*attrs {
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if last.is_doc_comment() {
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self.sess.emit_err(DocCommentDoesNotDocumentAnything {
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span: last.span,
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missing_comma: None,
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});
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} else if attrs.iter().any(|a| a.style == AttrStyle::Outer) {
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self.sess.emit_err(ExpectedStatementAfterOuterAttr { span: last.span });
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}
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}
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}
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fn recover_stmt_local_after_let(
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&mut self,
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lo: Span,
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attrs: AttrWrapper,
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subdiagnostic: fn(Span) -> InvalidVariableDeclarationSub,
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) -> PResult<'a, Stmt> {
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let stmt =
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self.collect_tokens_trailing_token(attrs, ForceCollect::Yes, |this, attrs| {
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let local = this.parse_local(attrs)?;
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// FIXME - maybe capture semicolon in recovery?
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Ok((
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this.mk_stmt(lo.to(this.prev_token.span), StmtKind::Local(local)),
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TrailingToken::None,
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))
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})?;
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self.sess.emit_err(InvalidVariableDeclaration { span: lo, sub: subdiagnostic(lo) });
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Ok(stmt)
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}
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fn parse_local_mk(
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&mut self,
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lo: Span,
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attrs: AttrWrapper,
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capture_semi: bool,
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force_collect: ForceCollect,
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) -> PResult<'a, Stmt> {
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self.collect_tokens_trailing_token(attrs, force_collect, |this, attrs| {
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this.expect_keyword(kw::Let)?;
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let local = this.parse_local(attrs)?;
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let trailing = if capture_semi && this.token.kind == token::Semi {
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TrailingToken::Semi
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} else {
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TrailingToken::None
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};
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Ok((this.mk_stmt(lo.to(this.prev_token.span), StmtKind::Local(local)), trailing))
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})
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}
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/// Parses a local variable declaration.
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fn parse_local(&mut self, attrs: AttrVec) -> PResult<'a, P<Local>> {
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let lo = self.prev_token.span;
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if self.token.is_keyword(kw::Const) && self.look_ahead(1, |t| t.is_ident()) {
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self.sess.emit_err(ConstLetMutuallyExclusive { span: lo.to(self.token.span) });
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self.bump();
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}
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self.report_invalid_identifier_error()?;
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let (pat, colon) = self.parse_pat_before_ty(None, RecoverComma::Yes, "`let` bindings")?;
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let (err, ty) = if colon {
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// Save the state of the parser before parsing type normally, in case there is a `:`
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// instead of an `=` typo.
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let parser_snapshot_before_type = self.clone();
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let colon_sp = self.prev_token.span;
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match self.parse_ty() {
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Ok(ty) => (None, Some(ty)),
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Err(mut err) => {
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if let Ok(snip) = self.span_to_snippet(pat.span) {
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err.span_label(pat.span, format!("while parsing the type for `{}`", snip));
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}
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// we use noexpect here because we don't actually expect Eq to be here
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// but we are still checking for it in order to be able to handle it if
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// it is there
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let err = if self.check_noexpect(&token::Eq) {
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err.emit();
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None
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} else {
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// Rewind to before attempting to parse the type and continue parsing.
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let parser_snapshot_after_type =
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mem::replace(self, parser_snapshot_before_type);
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Some((parser_snapshot_after_type, colon_sp, err))
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};
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(err, None)
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}
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}
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} else {
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(None, None)
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};
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let init = match (self.parse_initializer(err.is_some()), err) {
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(Ok(init), None) => {
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// init parsed, ty parsed
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init
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}
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(Ok(init), Some((_, colon_sp, mut err))) => {
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// init parsed, ty error
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// Could parse the type as if it were the initializer, it is likely there was a
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// typo in the code: `:` instead of `=`. Add suggestion and emit the error.
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err.span_suggestion_short(
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colon_sp,
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"use `=` if you meant to assign",
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" =",
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Applicability::MachineApplicable,
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);
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err.emit();
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// As this was parsed successfully, continue as if the code has been fixed for the
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// rest of the file. It will still fail due to the emitted error, but we avoid
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// extra noise.
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init
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}
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(Err(init_err), Some((snapshot, _, ty_err))) => {
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// init error, ty error
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init_err.cancel();
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// Couldn't parse the type nor the initializer, only raise the type error and
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// return to the parser state before parsing the type as the initializer.
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// let x: <parse_error>;
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*self = snapshot;
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return Err(ty_err);
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}
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(Err(err), None) => {
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// init error, ty parsed
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// Couldn't parse the initializer and we're not attempting to recover a failed
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// parse of the type, return the error.
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return Err(err);
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}
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};
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let kind = match init {
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None => LocalKind::Decl,
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Some(init) => {
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if self.eat_keyword(kw::Else) {
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if self.token.is_keyword(kw::If) {
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// `let...else if`. Emit the same error that `parse_block()` would,
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// but explicitly point out that this pattern is not allowed.
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let msg = "conditional `else if` is not supported for `let...else`";
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return Err(self.error_block_no_opening_brace_msg(msg));
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}
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let els = self.parse_block()?;
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self.check_let_else_init_bool_expr(&init);
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self.check_let_else_init_trailing_brace(&init);
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LocalKind::InitElse(init, els)
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} else {
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LocalKind::Init(init)
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}
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}
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};
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let hi = if self.token == token::Semi { self.token.span } else { self.prev_token.span };
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Ok(P(ast::Local { ty, pat, kind, id: DUMMY_NODE_ID, span: lo.to(hi), attrs, tokens: None }))
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}
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/// report error for `let 1x = 123`
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pub fn report_invalid_identifier_error(&mut self) -> PResult<'a, ()> {
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if let token::Literal(lit) = self.token.uninterpolate().kind &&
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rustc_ast::MetaItemLit::from_token(&self.token).is_none() &&
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(lit.kind == token::LitKind::Integer || lit.kind == token::LitKind::Float) &&
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self.look_ahead(1, |t| matches!(t.kind, token::Eq) || matches!(t.kind, token::Colon ) ) {
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return Err(self.sess.create_err(InvalidIdentiferStartsWithNumber { span: self.token.span }));
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}
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Ok(())
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}
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fn check_let_else_init_bool_expr(&self, init: &ast::Expr) {
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if let ast::ExprKind::Binary(op, ..) = init.kind {
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if op.node.lazy() {
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self.sess.emit_err(InvalidExpressionInLetElse {
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span: init.span,
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operator: op.node.to_string(),
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sugg: WrapExpressionInParentheses {
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left: init.span.shrink_to_lo(),
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right: init.span.shrink_to_hi(),
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},
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});
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}
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}
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}
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fn check_let_else_init_trailing_brace(&self, init: &ast::Expr) {
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if let Some(trailing) = classify::expr_trailing_brace(init) {
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self.sess.emit_err(InvalidCurlyInLetElse {
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span: trailing.span.with_lo(trailing.span.hi() - BytePos(1)),
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sugg: WrapExpressionInParentheses {
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left: trailing.span.shrink_to_lo(),
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right: trailing.span.shrink_to_hi(),
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},
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});
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}
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}
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/// Parses the RHS of a local variable declaration (e.g., `= 14;`).
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fn parse_initializer(&mut self, eq_optional: bool) -> PResult<'a, Option<P<Expr>>> {
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let eq_consumed = match self.token.kind {
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token::BinOpEq(..) => {
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// Recover `let x <op>= 1` as `let x = 1`
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self.sess.emit_err(CompoundAssignmentExpressionInLet { span: self.token.span });
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self.bump();
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true
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}
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_ => self.eat(&token::Eq),
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};
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Ok(if eq_consumed || eq_optional { Some(self.parse_expr()?) } else { None })
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}
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/// Parses a block. No inner attributes are allowed.
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pub(super) fn parse_block(&mut self) -> PResult<'a, P<Block>> {
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let (attrs, block) = self.parse_inner_attrs_and_block()?;
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if let [.., last] = &*attrs {
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self.error_on_forbidden_inner_attr(
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last.span,
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super::attr::InnerAttrPolicy::Forbidden(Some(
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InnerAttrForbiddenReason::InCodeBlock,
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)),
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);
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}
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Ok(block)
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}
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|
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fn error_block_no_opening_brace_msg(
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&mut self,
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msg: &str,
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) -> DiagnosticBuilder<'a, ErrorGuaranteed> {
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let sp = self.token.span;
|
|
let mut e = self.struct_span_err(sp, msg);
|
|
let do_not_suggest_help = self.token.is_keyword(kw::In) || self.token == token::Colon;
|
|
|
|
// Check to see if the user has written something like
|
|
//
|
|
// if (cond)
|
|
// bar;
|
|
//
|
|
// which is valid in other languages, but not Rust.
|
|
match self.parse_stmt_without_recovery(false, ForceCollect::No) {
|
|
// If the next token is an open brace, e.g., we have:
|
|
//
|
|
// if expr other_expr {
|
|
// ^ ^ ^- lookahead(1) is a brace
|
|
// | |- current token is not "else"
|
|
// |- (statement we just parsed)
|
|
//
|
|
// the place-inside-a-block suggestion would be more likely wrong than right.
|
|
//
|
|
// FIXME(compiler-errors): this should probably parse an arbitrary expr and not
|
|
// just lookahead one token, so we can see if there's a brace after _that_,
|
|
// since we want to protect against:
|
|
// `if 1 1 + 1 {` being suggested as `if { 1 } 1 + 1 {`
|
|
// + +
|
|
Ok(Some(_))
|
|
if (!self.token.is_keyword(kw::Else)
|
|
&& self.look_ahead(1, |t| t == &token::OpenDelim(Delimiter::Brace)))
|
|
|| do_not_suggest_help => {}
|
|
// Do not suggest `if foo println!("") {;}` (as would be seen in test for #46836).
|
|
Ok(Some(Stmt { kind: StmtKind::Empty, .. })) => {}
|
|
Ok(Some(stmt)) => {
|
|
let stmt_own_line = self.sess.source_map().is_line_before_span_empty(sp);
|
|
let stmt_span = if stmt_own_line && self.eat(&token::Semi) {
|
|
// Expand the span to include the semicolon.
|
|
stmt.span.with_hi(self.prev_token.span.hi())
|
|
} else {
|
|
stmt.span
|
|
};
|
|
e.multipart_suggestion(
|
|
"try placing this code inside a block",
|
|
vec![
|
|
(stmt_span.shrink_to_lo(), "{ ".to_string()),
|
|
(stmt_span.shrink_to_hi(), " }".to_string()),
|
|
],
|
|
// Speculative; has been misleading in the past (#46836).
|
|
Applicability::MaybeIncorrect,
|
|
);
|
|
}
|
|
Err(e) => {
|
|
self.recover_stmt_(SemiColonMode::Break, BlockMode::Ignore);
|
|
e.cancel();
|
|
}
|
|
_ => {}
|
|
}
|
|
e.span_label(sp, "expected `{`");
|
|
e
|
|
}
|
|
|
|
fn error_block_no_opening_brace<T>(&mut self) -> PResult<'a, T> {
|
|
let tok = super::token_descr(&self.token);
|
|
let msg = format!("expected `{{`, found {}", tok);
|
|
Err(self.error_block_no_opening_brace_msg(&msg))
|
|
}
|
|
|
|
/// Parses a block. Inner attributes are allowed.
|
|
pub(super) fn parse_inner_attrs_and_block(&mut self) -> PResult<'a, (AttrVec, P<Block>)> {
|
|
self.parse_block_common(self.token.span, BlockCheckMode::Default, true)
|
|
}
|
|
|
|
/// Parses a block. Inner attributes are allowed.
|
|
pub(super) fn parse_block_common(
|
|
&mut self,
|
|
lo: Span,
|
|
blk_mode: BlockCheckMode,
|
|
can_be_struct_literal: bool,
|
|
) -> PResult<'a, (AttrVec, P<Block>)> {
|
|
maybe_whole!(self, NtBlock, |x| (AttrVec::new(), x));
|
|
|
|
let maybe_ident = self.prev_token.clone();
|
|
self.maybe_recover_unexpected_block_label();
|
|
if !self.eat(&token::OpenDelim(Delimiter::Brace)) {
|
|
return self.error_block_no_opening_brace();
|
|
}
|
|
|
|
let attrs = self.parse_inner_attributes()?;
|
|
let tail = match self.maybe_suggest_struct_literal(
|
|
lo,
|
|
blk_mode,
|
|
maybe_ident,
|
|
can_be_struct_literal,
|
|
) {
|
|
Some(tail) => tail?,
|
|
None => self.parse_block_tail(lo, blk_mode, AttemptLocalParseRecovery::Yes)?,
|
|
};
|
|
Ok((attrs, tail))
|
|
}
|
|
|
|
/// Parses the rest of a block expression or function body.
|
|
/// Precondition: already parsed the '{'.
|
|
pub(crate) fn parse_block_tail(
|
|
&mut self,
|
|
lo: Span,
|
|
s: BlockCheckMode,
|
|
recover: AttemptLocalParseRecovery,
|
|
) -> PResult<'a, P<Block>> {
|
|
let mut stmts = vec![];
|
|
let mut snapshot = None;
|
|
while !self.eat(&token::CloseDelim(Delimiter::Brace)) {
|
|
if self.token == token::Eof {
|
|
break;
|
|
}
|
|
if self.is_diff_marker(&TokenKind::BinOp(token::Shl), &TokenKind::Lt) {
|
|
// Account for `<<<<<<<` diff markers. We can't proactively error here because
|
|
// that can be a valid path start, so we snapshot and reparse only we've
|
|
// encountered another parse error.
|
|
snapshot = Some(self.create_snapshot_for_diagnostic());
|
|
}
|
|
let stmt = match self.parse_full_stmt(recover) {
|
|
Err(mut err) if recover.yes() => {
|
|
self.maybe_annotate_with_ascription(&mut err, false);
|
|
if let Some(ref mut snapshot) = snapshot {
|
|
snapshot.recover_diff_marker();
|
|
}
|
|
err.emit();
|
|
self.recover_stmt_(SemiColonMode::Ignore, BlockMode::Ignore);
|
|
Some(self.mk_stmt_err(self.token.span))
|
|
}
|
|
Ok(stmt) => stmt,
|
|
Err(err) => return Err(err),
|
|
};
|
|
if let Some(stmt) = stmt {
|
|
stmts.push(stmt);
|
|
} else {
|
|
// Found only `;` or `}`.
|
|
continue;
|
|
};
|
|
}
|
|
Ok(self.mk_block(stmts, s, lo.to(self.prev_token.span)))
|
|
}
|
|
|
|
/// Parses a statement, including the trailing semicolon.
|
|
pub fn parse_full_stmt(
|
|
&mut self,
|
|
recover: AttemptLocalParseRecovery,
|
|
) -> PResult<'a, Option<Stmt>> {
|
|
// Skip looking for a trailing semicolon when we have an interpolated statement.
|
|
maybe_whole!(self, NtStmt, |x| Some(x.into_inner()));
|
|
|
|
let Some(mut stmt) = self.parse_stmt_without_recovery(true, ForceCollect::No)? else {
|
|
return Ok(None);
|
|
};
|
|
|
|
let mut eat_semi = true;
|
|
match &mut stmt.kind {
|
|
// Expression without semicolon.
|
|
StmtKind::Expr(expr)
|
|
if self.token != token::Eof && classify::expr_requires_semi_to_be_stmt(expr) => {
|
|
// Just check for errors and recover; do not eat semicolon yet.
|
|
// `expect_one_of` returns PResult<'a, bool /* recovered */>
|
|
let replace_with_err =
|
|
match self.expect_one_of(&[], &[token::Semi, token::CloseDelim(Delimiter::Brace)]) {
|
|
// Recover from parser, skip type error to avoid extra errors.
|
|
Ok(true) => true,
|
|
Err(mut e) => {
|
|
if let TokenKind::DocComment(..) = self.token.kind &&
|
|
let Ok(snippet) = self.span_to_snippet(self.token.span) {
|
|
let sp = self.token.span;
|
|
let marker = &snippet[..3];
|
|
let (comment_marker, doc_comment_marker) = marker.split_at(2);
|
|
|
|
e.span_suggestion(
|
|
sp.with_hi(sp.lo() + BytePos(marker.len() as u32)),
|
|
&format!(
|
|
"add a space before `{}` to use a regular comment",
|
|
doc_comment_marker,
|
|
),
|
|
format!("{} {}", comment_marker, doc_comment_marker),
|
|
Applicability::MaybeIncorrect,
|
|
);
|
|
}
|
|
|
|
if let Err(mut e) =
|
|
self.check_mistyped_turbofish_with_multiple_type_params(e, expr)
|
|
{
|
|
if recover.no() {
|
|
return Err(e);
|
|
}
|
|
e.emit();
|
|
self.recover_stmt();
|
|
}
|
|
true
|
|
}
|
|
_ => false
|
|
};
|
|
if replace_with_err {
|
|
// We already emitted an error, so don't emit another type error
|
|
let sp = expr.span.to(self.prev_token.span);
|
|
*expr = self.mk_expr_err(sp);
|
|
}
|
|
}
|
|
StmtKind::Expr(_) | StmtKind::MacCall(_) => {}
|
|
StmtKind::Local(local) if let Err(e) = self.expect_semi() => {
|
|
// We might be at the `,` in `let x = foo<bar, baz>;`. Try to recover.
|
|
match &mut local.kind {
|
|
LocalKind::Init(expr) | LocalKind::InitElse(expr, _) => {
|
|
self.check_mistyped_turbofish_with_multiple_type_params(e, expr)?;
|
|
// We found `foo<bar, baz>`, have we fully recovered?
|
|
self.expect_semi()?;
|
|
}
|
|
LocalKind::Decl => return Err(e),
|
|
}
|
|
eat_semi = false;
|
|
}
|
|
StmtKind::Empty | StmtKind::Item(_) | StmtKind::Local(_) | StmtKind::Semi(_) => eat_semi = false,
|
|
}
|
|
|
|
if eat_semi && self.eat(&token::Semi) {
|
|
stmt = stmt.add_trailing_semicolon();
|
|
}
|
|
stmt.span = stmt.span.to(self.prev_token.span);
|
|
Ok(Some(stmt))
|
|
}
|
|
|
|
pub(super) fn mk_block(&self, stmts: Vec<Stmt>, rules: BlockCheckMode, span: Span) -> P<Block> {
|
|
P(Block {
|
|
stmts,
|
|
id: DUMMY_NODE_ID,
|
|
rules,
|
|
span,
|
|
tokens: None,
|
|
could_be_bare_literal: false,
|
|
})
|
|
}
|
|
|
|
pub(super) fn mk_stmt(&self, span: Span, kind: StmtKind) -> Stmt {
|
|
Stmt { id: DUMMY_NODE_ID, kind, span }
|
|
}
|
|
|
|
pub(super) fn mk_stmt_err(&self, span: Span) -> Stmt {
|
|
self.mk_stmt(span, StmtKind::Expr(self.mk_expr_err(span)))
|
|
}
|
|
|
|
pub(super) fn mk_block_err(&self, span: Span) -> P<Block> {
|
|
self.mk_block(vec![self.mk_stmt_err(span)], BlockCheckMode::Default, span)
|
|
}
|
|
}
|