Prepend "Get" to method name if method name conflicts with return type name.

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 4e86a88fc1c474a9a7b3a3be4d8b95e3e5c48a1e..267f617258d5e23e1edd491c175af87160939f15 100644
--- a/tools/clang/rewrite_to_chrome_style/RewriteToChromeStyle.cpp
+++ b/tools/clang/rewrite_to_chrome_style/RewriteToChromeStyle.cpp
@@ -337,15 +337,24 @@ bool IsProbablyConst(const clang::VarDecl& decl,
 }
 
 bool GetNameForDecl(const clang::FunctionDecl& decl,
-                    const clang::ASTContext& context,
+                    clang::ASTContext& context,

[Łukasz Anforowicz, 2016/08/24 18:09:49]

|match| function call below takes a non-const ASTContext& as an argument.

                     std::string& name) {
   name = decl.getName().str();
   name[0] = clang::toUppercase(name[0]);
+
+  // https://crbug.com/582312: Prepend "Get" if method name conflicts with type.
+  auto base_matcher =
+      hasCanonicalType(hasDeclaration(namedDecl(hasName(name))));

[dcheng, 2016/08/25 17:36:00]

Can we just pull the return type out of the FunctionDecl rather than running a
matcher?

I think we can just do:
  decl.getReturnType()->getBaseTypeIdentifier()->getName()

Which has the advantage that it'll work with multiple layers of indirection.

[Łukasz Anforowicz, 2016/08/25 18:30:40]

Thanks - done.  I didn't know about getBaseTypeIdentifier - I was using the
matcher mainly to strip pointers+references, but your suggestion is obviously
better.

RE: multiple layers of indirection - this might also be a problem in
https://codereview.chromium.org/2256913002 - I've left a comment there.

+  auto conflict_matcher = qualType(
+      anyOf(pointsTo(base_matcher), references(base_matcher), base_matcher));
+  if (!match(conflict_matcher, decl.getReturnType(), context).empty())
+    name = "Get" + name;
+
   return true;
 }
 
 bool GetNameForDecl(const clang::EnumConstantDecl& decl,
-                    const clang::ASTContext& context,
+                    clang::ASTContext& context,

[Łukasz Anforowicz, 2016/08/24 18:09:49]

Best to be consistent here (i.e. use non-const in all overloads) - otherwise
overload resolution + templates is very confusing (at one point I had non-const
only in 2 places - it resulted in a warning that one of the GetNameForDecl
overloads is unused... :-/ ).

                     std::string& name) {
   StringRef original_name = decl.getName();
 
@@ -372,7 +381,7 @@ bool GetNameForDecl(const clang::EnumConstantDecl& decl,
 }
 
 bool GetNameForDecl(const clang::FieldDecl& decl,
-                    const clang::ASTContext& context,
+                    clang::ASTContext& context,
                     std::string& name) {
   StringRef original_name = decl.getName();
   bool member_prefix = original_name.startswith(kBlinkFieldPrefix);
@@ -403,7 +412,7 @@ bool GetNameForConstant(const std::string& original_name, std::string& name) {
 }
 
 bool GetNameForDecl(const clang::VarDecl& decl,
-                    const clang::ASTContext& context,
+                    clang::ASTContext& context,
                     std::string& name) {
   StringRef original_name = decl.getName();
 
@@ -466,14 +475,14 @@ bool GetNameForDecl(const clang::VarDecl& decl,
 }
 
 bool GetNameForDecl(const clang::FunctionTemplateDecl& decl,
-                    const clang::ASTContext& context,
+                    clang::ASTContext& context,
                     std::string& name) {
   clang::FunctionDecl* templated_function = decl.getTemplatedDecl();
   return GetNameForDecl(*templated_function, context, name);
 }
 
 bool GetNameForDecl(const clang::NamedDecl& decl,
-                    const clang::ASTContext& context,
+                    clang::ASTContext& context,
                     std::string& name) {
   if (auto* function = clang::dyn_cast<clang::FunctionDecl>(&decl))
     return GetNameForDecl(*function, context, name);
@@ -491,7 +500,7 @@ bool GetNameForDecl(const clang::NamedDecl& decl,
 }
 
 bool GetNameForDecl(const clang::UsingDecl& decl,
-                    const clang::ASTContext& context,
+                    clang::ASTContext& context,
                     std::string& name) {
   assert(decl.shadow_size() > 0);