PR17567: Improve diagnostic for a mistyped constructor name. If we see something

that looks like a function declaration, except that it's missing a return type,
try typo-correcting it to the relevant constructor name.

In passing, fix a bug where the missing-type-specifier recovery codepath would
drop a preceding scope specifier on the floor, leading to follow-on diagnostics
and incorrect recovery for the auto-in-c++98 hack.

llvm-svn: 192644

1 files changed, 26 insertions, 0 deletions

diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp
index 6ec344d1e3c..655c9e2c3d0 100644
--- a/clang/lib/Sema/SemaDeclCXX.cpp
+++ b/clang/lib/Sema/SemaDeclCXX.cpp
@@ -1227,6 +1227,32 @@ bool Sema::isCurrentClassName(const IdentifierInfo &II, Scope *,
   return false;
 }
 
+/// \brief Determine whether the identifier II is a typo for the name of
+/// the class type currently being defined. If so, update it to the identifier
+/// that should have been used.
+bool Sema::isCurrentClassNameTypo(IdentifierInfo *&II, const CXXScopeSpec *SS) {
+  assert(getLangOpts().CPlusPlus && "No class names in C!");
+
+  if (!getLangOpts().SpellChecking)
+    return false;
+
+  CXXRecordDecl *CurDecl;
+  if (SS && SS->isSet() && !SS->isInvalid()) {
+    DeclContext *DC = computeDeclContext(*SS, true);
+    CurDecl = dyn_cast_or_null<CXXRecordDecl>(DC);
+  } else
+    CurDecl = dyn_cast_or_null<CXXRecordDecl>(CurContext);
+
+  if (CurDecl && CurDecl->getIdentifier() && II != CurDecl->getIdentifier() &&
+      3 * II->getName().edit_distance(CurDecl->getIdentifier()->getName())
+          < II->getLength()) {
+    II = CurDecl->getIdentifier();
+    return true;
+  }
+
+  return false;
+}
+
 /// \brief Determine whether the given class is a base class of the given
 /// class, including looking at dependent bases.
 static bool findCircularInheritance(const CXXRecordDecl *Class,