Write help for unexpected =>. Fixes rust-lang#98128

GKFX · GKFX · commit cc6c774a5a51 · 2022-06-18T22:07:14.000+01:00
diff --git a/compiler/rustc_parse/src/parser/diagnostics.rs b/compiler/rustc_parse/src/parser/diagnostics.rs
@@ -606,6 +606,8 @@ impl<'a> Parser<'a> {
             && expected.iter().any(|tok| matches!(tok, TokenType::Token(TokenKind::Gt)))
         {
             err.span_label(self.prev_token.span, "maybe try to close unmatched angle bracket");
+        } else if self.token == token::FatArrow {
+            err.help("closures are written `|a, b| a + b` and greater-than-or-equal is `>=`.");
         }
 
         let sp = if self.token == token::Eof {

Original file line number	Diff line number	Diff line change
`@@ -606,6 +606,8 @@ impl<'a> Parser<'a> {`
`606`	`606`	`&& expected.iter().any(\|tok\| matches!(tok, TokenType::Token(TokenKind::Gt)))`
`607`	`607`	`{`
`608`	`608`	`err.span_label(self.prev_token.span, "maybe try to close unmatched angle bracket");`
	`609`	`+ } else if self.token == token::FatArrow {`
	`610`	+ err.help("closures are written `\|a, b\| a + b` and greater-than-or-equal is `>=`.");
`609`	`611`	`}`
`610`	`612`
`611`	`613`	`let sp = if self.token == token::Eof {`