From 7239d7717188f6dc2b380a40335a0c8571be6502 Mon Sep 17 00:00:00 2001 From: Esteban Küber Date: Thu, 6 Jul 2017 14:29:55 -0700 Subject: Point at `:` when using it instead of `;` When triggering type ascription in such a way that we can infer a statement end was intended, add a suggestion for the change. Always point out the reason for the expectation of a type is due to type ascription. --- src/libsyntax/parse/parser.rs | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) (limited to 'src/libsyntax/parse') diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs index 74b2ea1df32..1b6c3cf94e4 100644 --- a/src/libsyntax/parse/parser.rs +++ b/src/libsyntax/parse/parser.rs @@ -2798,7 +2798,22 @@ impl<'a> Parser<'a> { lhs = self.parse_assoc_op_cast(lhs, lhs_span, ExprKind::Cast)?; continue } else if op == AssocOp::Colon { - lhs = self.parse_assoc_op_cast(lhs, lhs_span, ExprKind::Type)?; + lhs = match self.parse_assoc_op_cast(lhs, lhs_span, ExprKind::Type) { + Ok(lhs) => lhs, + Err(mut err) => { + err.span_label(self.span, + "expecting a type here because of type ascription"); + let cm = self.sess.codemap(); + let cur_pos = cm.lookup_char_pos(self.span.lo); + let op_pos = cm.lookup_char_pos(cur_op_span.hi); + if cur_pos.line != op_pos.line { + err.span_suggestion(cur_op_span, + "did you mean to end the statement here instead?", + ";".to_string()); + } + return Err(err); + } + }; continue } else if op == AssocOp::DotDot || op == AssocOp::DotDotDot { // If we didn’t have to handle `x..`/`x...`, it would be pretty easy to -- cgit 1.4.1-3-g733a5