diff options
Diffstat (limited to 'compiler/rustc_parse/src/lexer/tokentrees.rs')
| -rw-r--r-- | compiler/rustc_parse/src/lexer/tokentrees.rs | 150 |
1 files changed, 53 insertions, 97 deletions
diff --git a/compiler/rustc_parse/src/lexer/tokentrees.rs b/compiler/rustc_parse/src/lexer/tokentrees.rs index b2701817d..36fd1e37d 100644 --- a/compiler/rustc_parse/src/lexer/tokentrees.rs +++ b/compiler/rustc_parse/src/lexer/tokentrees.rs @@ -1,47 +1,31 @@ -use super::{StringReader, UnmatchedBrace}; +use super::diagnostics::report_suspicious_mismatch_block; +use super::diagnostics::same_identation_level; +use super::diagnostics::TokenTreeDiagInfo; +use super::{StringReader, UnmatchedDelim}; use rustc_ast::token::{self, Delimiter, Token}; use rustc_ast::tokenstream::{DelimSpan, Spacing, TokenStream, TokenTree}; use rustc_ast_pretty::pprust::token_to_string; -use rustc_data_structures::fx::FxHashMap; use rustc_errors::{PErr, PResult}; -use rustc_span::Span; pub(super) struct TokenTreesReader<'a> { string_reader: StringReader<'a>, /// The "next" token, which has been obtained from the `StringReader` but /// not yet handled by the `TokenTreesReader`. token: Token, - /// Stack of open delimiters and their spans. Used for error message. - open_braces: Vec<(Delimiter, Span)>, - unmatched_braces: Vec<UnmatchedBrace>, - /// The type and spans for all braces - /// - /// Used only for error recovery when arriving to EOF with mismatched braces. - matching_delim_spans: Vec<(Delimiter, Span, Span)>, - last_unclosed_found_span: Option<Span>, - /// Collect empty block spans that might have been auto-inserted by editors. - last_delim_empty_block_spans: FxHashMap<Delimiter, Span>, - /// Collect the spans of braces (Open, Close). Used only - /// for detecting if blocks are empty and only braces. - matching_block_spans: Vec<(Span, Span)>, + diag_info: TokenTreeDiagInfo, } impl<'a> TokenTreesReader<'a> { pub(super) fn parse_all_token_trees( string_reader: StringReader<'a>, - ) -> (PResult<'a, TokenStream>, Vec<UnmatchedBrace>) { + ) -> (PResult<'a, TokenStream>, Vec<UnmatchedDelim>) { let mut tt_reader = TokenTreesReader { string_reader, token: Token::dummy(), - open_braces: Vec::new(), - unmatched_braces: Vec::new(), - matching_delim_spans: Vec::new(), - last_unclosed_found_span: None, - last_delim_empty_block_spans: FxHashMap::default(), - matching_block_spans: Vec::new(), + diag_info: TokenTreeDiagInfo::default(), }; let res = tt_reader.parse_token_trees(/* is_delimited */ false); - (res, tt_reader.unmatched_braces) + (res, tt_reader.diag_info.unmatched_delims) } // Parse a stream of tokens into a list of `TokenTree`s. @@ -50,7 +34,7 @@ impl<'a> TokenTreesReader<'a> { let mut buf = Vec::new(); loop { match self.token.kind { - token::OpenDelim(delim) => buf.push(self.parse_token_tree_open_delim(delim)), + token::OpenDelim(delim) => buf.push(self.parse_token_tree_open_delim(delim)?), token::CloseDelim(delim) => { return if is_delimited { Ok(TokenStream::new(buf)) @@ -59,10 +43,11 @@ impl<'a> TokenTreesReader<'a> { }; } token::Eof => { - if is_delimited { - self.eof_err().emit(); - } - return Ok(TokenStream::new(buf)); + return if is_delimited { + Err(self.eof_err()) + } else { + Ok(TokenStream::new(buf)) + }; } _ => { // Get the next normal token. This might require getting multiple adjacent @@ -92,9 +77,9 @@ impl<'a> TokenTreesReader<'a> { fn eof_err(&mut self) -> PErr<'a> { let msg = "this file contains an unclosed delimiter"; let mut err = self.string_reader.sess.span_diagnostic.struct_span_err(self.token.span, msg); - for &(_, sp) in &self.open_braces { + for &(_, sp) in &self.diag_info.open_braces { err.span_label(sp, "unclosed delimiter"); - self.unmatched_braces.push(UnmatchedBrace { + self.diag_info.unmatched_delims.push(UnmatchedDelim { expected_delim: Delimiter::Brace, found_delim: None, found_span: self.token.span, @@ -103,69 +88,53 @@ impl<'a> TokenTreesReader<'a> { }); } - if let Some((delim, _)) = self.open_braces.last() { - if let Some((_, open_sp, close_sp)) = - self.matching_delim_spans.iter().find(|(d, open_sp, close_sp)| { - let sm = self.string_reader.sess.source_map(); - if let Some(close_padding) = sm.span_to_margin(*close_sp) { - if let Some(open_padding) = sm.span_to_margin(*open_sp) { - return delim == d && close_padding != open_padding; - } - } - false - }) - // these are in reverse order as they get inserted on close, but - { - // we want the last open/first close - err.span_label(*open_sp, "this delimiter might not be properly closed..."); - err.span_label(*close_sp, "...as it matches this but it has different indentation"); - } + if let Some((delim, _)) = self.diag_info.open_braces.last() { + report_suspicious_mismatch_block( + &mut err, + &self.diag_info, + &self.string_reader.sess.source_map(), + *delim, + ) } err } - fn parse_token_tree_open_delim(&mut self, open_delim: Delimiter) -> TokenTree { + fn parse_token_tree_open_delim(&mut self, open_delim: Delimiter) -> PResult<'a, TokenTree> { // The span for beginning of the delimited section let pre_span = self.token.span; - self.open_braces.push((open_delim, self.token.span)); + self.diag_info.open_braces.push((open_delim, self.token.span)); // Parse the token trees within the delimiters. // We stop at any delimiter so we can try to recover if the user // uses an incorrect delimiter. - let tts = self.parse_token_trees(/* is_delimited */ true).unwrap(); + let tts = self.parse_token_trees(/* is_delimited */ true)?; // Expand to cover the entire delimited token tree let delim_span = DelimSpan::from_pair(pre_span, self.token.span); + let sm = self.string_reader.sess.source_map(); match self.token.kind { // Correct delimiter. token::CloseDelim(close_delim) if close_delim == open_delim => { - let (open_brace, open_brace_span) = self.open_braces.pop().unwrap(); + let (open_brace, open_brace_span) = self.diag_info.open_braces.pop().unwrap(); let close_brace_span = self.token.span; - if tts.is_empty() { + if tts.is_empty() && close_delim == Delimiter::Brace { let empty_block_span = open_brace_span.to(close_brace_span); - let sm = self.string_reader.sess.source_map(); if !sm.is_multiline(empty_block_span) { // Only track if the block is in the form of `{}`, otherwise it is // likely that it was written on purpose. - self.last_delim_empty_block_spans.insert(open_delim, empty_block_span); + self.diag_info.empty_block_spans.push(empty_block_span); } } - //only add braces + // only add braces if let (Delimiter::Brace, Delimiter::Brace) = (open_brace, open_delim) { - self.matching_block_spans.push((open_brace_span, close_brace_span)); + // Add all the matching spans, we will sort by span later + self.diag_info.matching_block_spans.push((open_brace_span, close_brace_span)); } - if self.open_braces.is_empty() { - // Clear up these spans to avoid suggesting them as we've found - // properly matched delimiters so far for an entire block. - self.matching_delim_spans.clear(); - } else { - self.matching_delim_spans.push((open_brace, open_brace_span, close_brace_span)); - } // Move past the closing delimiter. self.token = self.string_reader.next_token().0; } @@ -174,28 +143,25 @@ impl<'a> TokenTreesReader<'a> { let mut unclosed_delimiter = None; let mut candidate = None; - if self.last_unclosed_found_span != Some(self.token.span) { + if self.diag_info.last_unclosed_found_span != Some(self.token.span) { // do not complain about the same unclosed delimiter multiple times - self.last_unclosed_found_span = Some(self.token.span); + self.diag_info.last_unclosed_found_span = Some(self.token.span); // This is a conservative error: only report the last unclosed // delimiter. The previous unclosed delimiters could actually be // closed! The parser just hasn't gotten to them yet. - if let Some(&(_, sp)) = self.open_braces.last() { + if let Some(&(_, sp)) = self.diag_info.open_braces.last() { unclosed_delimiter = Some(sp); }; - let sm = self.string_reader.sess.source_map(); - if let Some(current_padding) = sm.span_to_margin(self.token.span) { - for (brace, brace_span) in &self.open_braces { - if let Some(padding) = sm.span_to_margin(*brace_span) { - // high likelihood of these two corresponding - if current_padding == padding && brace == &close_delim { - candidate = Some(*brace_span); - } - } + for (brace, brace_span) in &self.diag_info.open_braces { + if same_identation_level(&sm, self.token.span, *brace_span) + && brace == &close_delim + { + // high likelihood of these two corresponding + candidate = Some(*brace_span); } } - let (tok, _) = self.open_braces.pop().unwrap(); - self.unmatched_braces.push(UnmatchedBrace { + let (tok, _) = self.diag_info.open_braces.pop().unwrap(); + self.diag_info.unmatched_delims.push(UnmatchedDelim { expected_delim: tok, found_delim: Some(close_delim), found_span: self.token.span, @@ -203,7 +169,7 @@ impl<'a> TokenTreesReader<'a> { candidate_span: candidate, }); } else { - self.open_braces.pop(); + self.diag_info.open_braces.pop(); } // If the incorrect delimiter matches an earlier opening @@ -213,7 +179,7 @@ impl<'a> TokenTreesReader<'a> { // fn foo() { // bar(baz( // } // Incorrect delimiter but matches the earlier `{` - if !self.open_braces.iter().any(|&(b, _)| b == close_delim) { + if !self.diag_info.open_braces.iter().any(|&(b, _)| b == close_delim) { self.token = self.string_reader.next_token().0; } } @@ -225,7 +191,7 @@ impl<'a> TokenTreesReader<'a> { _ => unreachable!(), } - TokenTree::Delimited(delim_span, open_delim, tts) + Ok(TokenTree::Delimited(delim_span, open_delim, tts)) } fn close_delim_err(&mut self, delim: Delimiter) -> PErr<'a> { @@ -236,22 +202,12 @@ impl<'a> TokenTreesReader<'a> { let mut err = self.string_reader.sess.span_diagnostic.struct_span_err(self.token.span, &msg); - // Braces are added at the end, so the last element is the biggest block - if let Some(parent) = self.matching_block_spans.last() { - if let Some(span) = self.last_delim_empty_block_spans.remove(&delim) { - // Check if the (empty block) is in the last properly closed block - if (parent.0.to(parent.1)).contains(span) { - err.span_label(span, "block is empty, you might have not meant to close it"); - } else { - err.span_label(parent.0, "this opening brace..."); - err.span_label(parent.1, "...matches this closing brace"); - } - } else { - err.span_label(parent.0, "this opening brace..."); - err.span_label(parent.1, "...matches this closing brace"); - } - } - + report_suspicious_mismatch_block( + &mut err, + &self.diag_info, + &self.string_reader.sess.source_map(), + delim, + ); err.span_label(self.token.span, "unexpected closing delimiter"); err } |