[clang-tidy] Ignore namespaced and C++ member functions in google-objc-function-naming check 🙈

Summary: The google-objc-function-naming check applies to functions that are not namespaced and should not be applied to C++ member functions. Such function declarations should be ignored by the check to avoid false positives in Objective-C++ sources.

Reviewers: benhamilton, aaron.ballman

Reviewed By: aaron.ballman

Subscribers: xazax.hun, cfe-commits

Differential Revision: https://reviews.llvm.org/D55101

2 files changed, 33 insertions, 2 deletions

diff --git a/clang-tools-extra/clang-tidy/google/FunctionNamingCheck.cpp b/clang-tools-extra/clang-tidy/google/FunctionNamingCheck.cpp
index 7aeadd38c02..6d07472ef54 100644
--- a/clang-tools-extra/clang-tidy/google/FunctionNamingCheck.cpp
+++ b/clang-tools-extra/clang-tidy/google/FunctionNamingCheck.cpp
@@ -98,8 +98,9 @@ void FunctionNamingCheck::registerMatchers(MatchFinder *Finder) {
   // main.
   Finder->addMatcher(
       functionDecl(
-          unless(isExpansionInSystemHeader()),
-          unless(anyOf(isMain(), matchesName(validFunctionNameRegex(true)),
+          unless(anyOf(isExpansionInSystemHeader(), cxxMethodDecl(),
+                       hasAncestor(namespaceDecl()), isMain(),
+                       matchesName(validFunctionNameRegex(true)),
                        allOf(isStaticStorageClass(),
                              matchesName(validFunctionNameRegex(false))))))
           .bind("function"),
diff --git a/clang-tools-extra/test/clang-tidy/google-objc-function-naming.mm b/clang-tools-extra/test/clang-tidy/google-objc-function-naming.mm
new file mode 100644
index 00000000000..2e894575528
--- /dev/null
+++ b/clang-tools-extra/test/clang-tidy/google-objc-function-naming.mm
@@ -0,0 +1,30 @@
+// RUN: %check_clang_tidy %s google-objc-function-naming %t
+
+void printSomething() {}
+// CHECK-MESSAGES: :[[@LINE-1]]:6: warning: function name 'printSomething' not
+// using function naming conventions described by Google Objective-C style guide
+
+void PrintSomething() {}
+// CHECK-MESSAGES: :[[@LINE-1]]:6: warning: function name 'PrintSomething' not
+// using function naming conventions described by Google Objective-C style guide
+
+void ABCBad_Name() {}
+// CHECK-MESSAGES: :[[@LINE-1]]:6: warning: function name 'ABCBad_Name' not
+// using function naming conventions described by Google Objective-C style guide
+
+namespace {
+
+int foo() { return 0; }
+
+}
+
+namespace bar {
+
+int convert() { return 0; }
+
+}
+
+class Baz {
+public:
+  int value() { return 0; }
+};