[clang] [clang] NestedNameSpecifier typo correction fix (PR #181239)

[Shafik Yaghmour via cfe-commits]

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@@ -381,11 +381,17 @@ namespace {
 class NestedNameSpecifierValidatorCCC final
     : public CorrectionCandidateCallback {
 public:
-  explicit NestedNameSpecifierValidatorCCC(Sema &SRef)
-      : SRef(SRef) {}
+  explicit NestedNameSpecifierValidatorCCC(Sema &SRef, bool HasQualifier)
+      : SRef(SRef), HasQualifier(HasQualifier) {}
 
   bool ValidateCandidate(const TypoCorrection &candidate) override {
-    return SRef.isAcceptableNestedNameSpecifier(candidate.getCorrectionDecl());
+    const NamedDecl *ND = candidate.getCorrectionDecl();
+    if (!SRef.isAcceptableNestedNameSpecifier(ND))
+      return false;
+    // A template type parameter cannot have a nested name specifier.
+    if (HasQualifier && isa<TemplateTypeParmDecl>(ND))
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shafik wrote:

This has four cases but we only have one test, we should really have four tests that cover all combinations to ensure it works as expected. 

https://github.com/llvm/llvm-project/pull/181239