[cfe-dev] libclang: Spelling on typedefs lacks namespaces

[Michael via cfe-dev]

Cool, sounds good. It's a few more tests to fix than expected, but stay 
tuned for a patch.

Thanks

Michael

On 02/10/2017 03:25 PM, Alex L wrote:
> Hi Michael,
>
> Thanks for the detailed report! I believe you're
> correct, clang_getTypeSpelling should return the fully qualified name
> for the typedefs since it does so for the other types.
>
> It looks like you're on the right track with the diff that you've shown.
> I would encourage you to submit it as a patch (with tests)
> to cfe-commits, either by using Phabricator
> (http://llvm.org/docs/Phabricator.html) or by emailing the patch
> directly to the list.
>
> Cheers,
> Alex
>
>
> On 10 February 2017 at 12:39, Michael via cfe-dev
> <cfe-dev at lists.llvm.org <mailto:cfe-dev at lists.llvm.org>> wrote:
>
>     Hi
>
>     I'm using libclang to parse header files and generate code from
>     them. I found that clang_getTypeSpelling() usually includes the
>     namespace(s) a type was declared in. However with the exception
>     being typedefs (and same for "using A = B"). Not sure if this is a
>     bug or intended behavior, but it seems at least inconsistent. I also
>     couldn't really find a good workaround for this. I'd have to
>     manually figure out all typedefs (not just pure typedefs, they could
>     also be nested template arguments or whatever) and then their
>     originating namespaces. This is a bit cumbersome and not really
>     straight forward. Getting the canonical type is also not really a
>     solution as I would like to keep the typedefs.
>
>     Minimal example:
>
>     namespace foo {
>     class Bar {
>     };
>     typedef Bar BarDef;
>     }
>
>     clang_getTypeSpelling on "Bar" (kind "Record") gives: "foo::Bar"
>     clang_getTypeSpelling on "BarDef" (kind "Typedef") gives: "BarDef"
>     (<== missing "foo::")
>
>
>     I had a look into the clang sources. It seems this little patch
>     would fix the problem. This was pure guess work, I don't know what
>     deeper consequences this might have.
>
>     Index: lib/AST/TypePrinter.cpp
>     ===================================================================
>     --- lib/AST/TypePrinter.cpp     (revision 294732)
>     +++ lib/AST/TypePrinter.cpp     (working copy)
>     @@ -96,7 +96,7 @@
>
>          static bool canPrefixQualifiers(const Type *T, bool
>     &NeedARCStrongQualifier);
>          void spaceBeforePlaceHolder(raw_ostream &OS);
>     -    void printTypeSpec(const NamedDecl *D, raw_ostream &OS);
>     +    void printTypeSpec(NamedDecl *D, raw_ostream &OS);
>
>          void printBefore(const Type *ty, Qualifiers qs, raw_ostream &OS);
>          void printBefore(QualType T, raw_ostream &OS);
>     @@ -798,7 +798,14 @@
>        printAfter(T->getReturnType(), OS);
>      }
>
>     -void TypePrinter::printTypeSpec(const NamedDecl *D, raw_ostream &OS) {
>     +void TypePrinter::printTypeSpec(NamedDecl *D, raw_ostream &OS) {
>     +
>     +  // Compute the full nested-name-specifier for this type.
>     +  // In C, this will always be empty except when the type
>     +  // being printed is anonymous within other Record.
>     +  if (!Policy.SuppressScope)
>     +    AppendScope(D->getDeclContext(), OS);
>     +
>        IdentifierInfo *II = D->getIdentifier();
>        OS << II->getName();
>        spaceBeforePlaceHolder(OS);
>
>     (I would of course also fix the unit tests if needed)
>
>     Please let me know what you think.
>
>     Thanks
>
>     Michael
>
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