[clang] [clang][TypePrinter] Replace AppendScope with printNestedNameSpecifier (PR #168534)

[Vlad Serebrennikov via cfe-commits]

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@@ -1241,7 +1241,7 @@ namespace cwg686 { // cwg686: 3.0
 #endif
     struct N {
       operator struct O{}(){};
-      // expected-error at -1 {{'N::O' cannot be defined in a type specifier}}
+      // expected-error at -1 {{'cwg686::f()::N::O' cannot be defined in a type specifier}}
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Endilll wrote:

Sorry, I meant a test elsewhere, e.g. in `clang/AST` directory. DR test here is not a good fit to test compiler behavior per se, because its contents are derived from the Standard wording. In other words, your new `f2` could easily be deleted in the future as a duplicate case, and no one will notice reduction in coverage.

https://github.com/llvm/llvm-project/pull/168534