Prepending "Get" when type with conflicting name is hidden inside return type.

tools/clang/rewrite_to_chrome_style/RewriteToChromeStyle.cpp

Index: tools/clang/rewrite_to_chrome_style/RewriteToChromeStyle.cpp
diff --git a/tools/clang/rewrite_to_chrome_style/RewriteToChromeStyle.cpp b/tools/clang/rewrite_to_chrome_style/RewriteToChromeStyle.cpp
index 600adeb807171fb69775d72155cf35aa883edac9..da3945dd1af6d22dd196cf5e98d40837ca3f10c7 100644
--- a/tools/clang/rewrite_to_chrome_style/RewriteToChromeStyle.cpp
+++ b/tools/clang/rewrite_to_chrome_style/RewriteToChromeStyle.cpp
@@ -290,6 +290,10 @@ bool IsProbablyConst(const clang::VarDecl& decl,
   return initializer->isEvaluatable(context);
 }
 
+AST_MATCHER_P(clang::QualType, hasString, std::string, ExpectedString) {
+  return ExpectedString == Node.getAsString();
+}
+
 bool GetNameForDecl(const clang::FunctionDecl& decl,
                     clang::ASTContext& context,
                     std::string& name) {
@@ -297,9 +301,14 @@ bool GetNameForDecl(const clang::FunctionDecl& decl,
   name[0] = clang::toUppercase(name[0]);
 
   // https://crbug.com/582312: Prepend "Get" if method name conflicts with type.
-  const clang::IdentifierInfo* return_type =
-      decl.getReturnType().getBaseTypeIdentifier();
-  if (return_type && return_type->getName() == name)
+  auto type_with_same_name_as_function = qualType(
+      anyOf(hasDeclaration(namedDecl(hasName(name))), hasString(name)));

[Łukasz Anforowicz, 2016/09/07 23:14:28]

Without |hasString| we wouldn't properly handle the new test case from
functions-xxx.cc that goes through a typedef/using declaration:

class Foo582312 {};
using Bar = Foo582312;
static Bar* bar() {
  return nullptr;
}

I am not happy with |hasString| but I have tried various other things and I was
not able to work around the fact that QualType's -> goes directly to the final
type (so hasDeclaration matches the final type and not the intermediate types).

[danakj, 2016/09/08 23:30:40]

Can you leave a comment here saying that hasName() gives the true name, which
can differ from how it's written (ie typedefs) and hasString() gives the true
way it is written?

[Łukasz Anforowicz, 2016/09/09 00:20:35]

Done.

+  auto type_containing_same_name_as_function =
+      qualType(anyOf(type_with_same_name_as_function,
+                     hasDescendant(type_with_same_name_as_function)));

[Łukasz Anforowicz, 2016/09/07 23:14:28]

|hasDescendant| helps catch the RefPtr<SameNameAsFunction> case.

+  auto conflict_matcher =
+      functionDecl(returns(type_containing_same_name_as_function));
+  if (!match(conflict_matcher, decl, context).empty())
     name = "Get" + name;
 
   return true;