Improve error recovery when we see ':' and expect a ';'.

I, at least, make this typo all the time.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@113243 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 20 insertions, 0 deletions

diff --git a/lib/Parse/Parser.cpp b/lib/Parse/Parser.cpp
index ca06ba72f6..02802773a0 100644
--- a/lib/Parse/Parser.cpp
+++ b/lib/Parse/Parser.cpp
@@ -133,6 +133,13 @@ SourceLocation Parser::MatchRHSPunctuation(tok::TokenKind RHSTok,
   return R;
 }
 
+static bool IsCommonTypo(tok::TokenKind ExpectedTok, const Token &Tok) {
+  switch (ExpectedTok) {
+  case tok::semi: return Tok.is(tok::colon); // : for ;
+  default: return false;
+  }
+}
+
 /// ExpectAndConsume - The parser expects that 'ExpectedTok' is next in the
 /// input.  If so, it is consumed and false is returned.
 ///
@@ -146,6 +153,19 @@ bool Parser::ExpectAndConsume(tok::TokenKind ExpectedTok, unsigned DiagID,
     return false;
   }
 
+  // Detect common single-character typos and resume.
+  if (IsCommonTypo(ExpectedTok, Tok)) {
+    SourceLocation Loc = Tok.getLocation();
+    Diag(Loc, DiagID)
+      << Msg
+      << FixItHint::CreateReplacement(SourceRange(Loc),
+                                      getTokenSimpleSpelling(ExpectedTok));
+    ConsumeAnyToken();
+
+    // Pretend there wasn't a problem.
+    return false;
+  }
+
   const char *Spelling = 0;
   SourceLocation EndLoc = PP.getLocForEndOfToken(PrevTokLocation);
   if (EndLoc.isValid() &&