rewrite_to_chrome_style: Don't rename swap() functions.

These are used for ADL tricks with std::swap, and need to stay
lowercase.

R=dcheng
BUG=584526

Review URL: https://codereview.chromium.org/1676463004

Cr-Commit-Position: refs/heads/master@{#373911}

3 files changed, 27 insertions, 1 deletions

diff --git a/tools/clang/rewrite_to_chrome_style/RewriteToChromeStyle.cpp b/tools/clang/rewrite_to_chrome_style/RewriteToChromeStyle.cpp
index b69732b..6df3096 100644
--- a/tools/clang/rewrite_to_chrome_style/RewriteToChromeStyle.cpp
+++ b/tools/clang/rewrite_to_chrome_style/RewriteToChromeStyle.cpp
@@ -178,7 +178,17 @@ bool IsProbablyConst(const clang::VarDecl& decl,
 bool GetNameForDecl(const clang::FunctionDecl& decl,
                     const clang::ASTContext& context,
                     std::string& name) {
-  name = decl.getName().str();
+  StringRef original_name = decl.getName();
+
+  // Some functions shouldn't be renamed because reasons.
+  // - swap() methods should match the signature of std::swap for ADL tricks.
+  static const char* kBlacklist[] = {"swap"};
+  for (const auto& b : kBlacklist) {
+    if (original_name == b)
+      return false;
+  }
+
+  name = original_name.str();
   name[0] = clang::toUppercase(name[0]);
   return true;
 }
diff --git a/tools/clang/rewrite_to_chrome_style/tests/functions-expected.cc b/tools/clang/rewrite_to_chrome_style/tests/functions-expected.cc
index b218840d..ed8928b 100644
--- a/tools/clang/rewrite_to_chrome_style/tests/functions-expected.cc
+++ b/tools/clang/rewrite_to_chrome_style/tests/functions-expected.cc
@@ -25,6 +25,11 @@ void Begin() {}
 void Trace() {}
 void Lock() {}
 
+class SwapType {};
+
+// swap() functions are not renamed.
+void swap(SwapType& a, SwapType& b) {}
+
 // Note: F is already Google style and should not change.
 void F() {
   // Test referencing a function without calling it.
@@ -37,4 +42,7 @@ using blink::TestFunctionThatTakesTwoInts;
 
 void G() {
   TestFunctionThatTakesTwoInts(1, 2);
+
+  blink::SwapType a, b;
+  swap(a, b);
 }
diff --git a/tools/clang/rewrite_to_chrome_style/tests/functions-original.cc b/tools/clang/rewrite_to_chrome_style/tests/functions-original.cc
index c416d38..14530c6 100644
--- a/tools/clang/rewrite_to_chrome_style/tests/functions-original.cc
+++ b/tools/clang/rewrite_to_chrome_style/tests/functions-original.cc
@@ -25,6 +25,11 @@ void begin() {}
 void trace() {}
 void lock() {}
 
+class SwapType {};
+
+// swap() functions are not renamed.
+void swap(SwapType& a, SwapType& b) {}
+
 // Note: F is already Google style and should not change.
 void F() {
   // Test referencing a function without calling it.
@@ -37,4 +42,7 @@ using blink::testFunctionThatTakesTwoInts;
 
 void G() {
   testFunctionThatTakesTwoInts(1, 2);
+
+  blink::SwapType a, b;
+  swap(a, b);
 }