diff options
Diffstat (limited to 'compiler/rustc_parse/src/parser/pat.rs')
-rw-r--r-- | compiler/rustc_parse/src/parser/pat.rs | 57 |
1 files changed, 45 insertions, 12 deletions
diff --git a/compiler/rustc_parse/src/parser/pat.rs b/compiler/rustc_parse/src/parser/pat.rs index c317d9636..fdf365178 100644 --- a/compiler/rustc_parse/src/parser/pat.rs +++ b/compiler/rustc_parse/src/parser/pat.rs @@ -938,7 +938,8 @@ impl<'a> Parser<'a> { let mut etc = false; let mut ate_comma = true; let mut delayed_err: Option<DiagnosticBuilder<'a, ErrorGuaranteed>> = None; - let mut etc_span = None; + let mut first_etc_and_maybe_comma_span = None; + let mut last_non_comma_dotdot_span = None; while self.token != token::CloseDelim(Delimiter::Brace) { let attrs = match self.parse_outer_attributes() { @@ -969,12 +970,27 @@ impl<'a> Parser<'a> { { etc = true; let mut etc_sp = self.token.span; + if first_etc_and_maybe_comma_span.is_none() { + if let Some(comma_tok) = self + .look_ahead(1, |t| if *t == token::Comma { Some(t.clone()) } else { None }) + { + let nw_span = self + .sess + .source_map() + .span_extend_to_line(comma_tok.span) + .trim_start(comma_tok.span.shrink_to_lo()) + .map(|s| self.sess.source_map().span_until_non_whitespace(s)); + first_etc_and_maybe_comma_span = nw_span.map(|s| etc_sp.to(s)); + } else { + first_etc_and_maybe_comma_span = + Some(self.sess.source_map().span_until_non_whitespace(etc_sp)); + } + } self.recover_bad_dot_dot(); self.bump(); // `..` || `...` || `_` if self.token == token::CloseDelim(Delimiter::Brace) { - etc_span = Some(etc_sp); break; } let token_str = super::token_descr(&self.token); @@ -996,7 +1012,6 @@ impl<'a> Parser<'a> { ate_comma = true; } - etc_span = Some(etc_sp.until(self.token.span)); if self.token == token::CloseDelim(Delimiter::Brace) { // If the struct looks otherwise well formed, recover and continue. if let Some(sp) = comma_sp { @@ -1040,6 +1055,9 @@ impl<'a> Parser<'a> { } }?; ate_comma = this.eat(&token::Comma); + + last_non_comma_dotdot_span = Some(this.prev_token.span); + // We just ate a comma, so there's no need to use // `TrailingToken::Comma` Ok((field, TrailingToken::None)) @@ -1049,15 +1067,30 @@ impl<'a> Parser<'a> { } if let Some(mut err) = delayed_err { - if let Some(etc_span) = etc_span { - err.multipart_suggestion( - "move the `..` to the end of the field list", - vec![ - (etc_span, String::new()), - (self.token.span, format!("{}.. }}", if ate_comma { "" } else { ", " })), - ], - Applicability::MachineApplicable, - ); + if let Some(first_etc_span) = first_etc_and_maybe_comma_span { + if self.prev_token == token::DotDot { + // We have `.., x, ..`. + err.multipart_suggestion( + "remove the starting `..`", + vec![(first_etc_span, String::new())], + Applicability::MachineApplicable, + ); + } else { + if let Some(last_non_comma_dotdot_span) = last_non_comma_dotdot_span { + // We have `.., x`. + err.multipart_suggestion( + "move the `..` to the end of the field list", + vec![ + (first_etc_span, String::new()), + ( + self.token.span.to(last_non_comma_dotdot_span.shrink_to_hi()), + format!("{} .. }}", if ate_comma { "" } else { "," }), + ), + ], + Applicability::MachineApplicable, + ); + } + } } err.emit(); } |