Index: clang/lib/Format/NamespaceEndCommentsFixer.cpp
===================================================================
--- clang/lib/Format/NamespaceEndCommentsFixer.cpp
+++ clang/lib/Format/NamespaceEndCommentsFixer.cpp
@@ -174,7 +174,8 @@
                   llvm::Regex::IgnoreCase);
   static const llvm::Regex NamespaceMacroCommentPattern =
       llvm::Regex("^/[/*] *(end (of )?)? *(anonymous|unnamed)? *"
-                  "([a-zA-Z0-9_]+)\\(([a-zA-Z0-9:_]*)\\)\\.? *(\\*/)?$",
+                  // NamespaceMacro arguments can also be string literals.
+                  "([a-zA-Z0-9_]+)\\(([a-zA-Z0-9:_]*|\".+\")\\)\\.? *(\\*/)?$",
                   llvm::Regex::IgnoreCase);
 
   SmallVector<StringRef, 8> Groups;
Index: clang/unittests/Format/NamespaceEndCommentsFixerTest.cpp
===================================================================
--- clang/unittests/Format/NamespaceEndCommentsFixerTest.cpp
+++ clang/unittests/Format/NamespaceEndCommentsFixerTest.cpp
@@ -40,8 +40,30 @@
         Code,
         /*Ranges=*/{1, tooling::Range(0, Code.size())}, Style);
   }
+
+  bool isFormatted(StringRef Code, const std::vector<tooling::Range> &Ranges,
+                   const FormatStyle &Style = getLLVMStyle()) const {
+    return clang::format::fixNamespaceEndComments(Style, Code, Ranges,
+                                                  "<stdin>")
+        .empty();
+  }
+
+  bool isFormatted(StringRef Code,
+                   const FormatStyle &Style = getLLVMStyle()) const {
+    return isFormatted(Code, {1, tooling::Range(0, Code.size())}, Style);
+  }
 };
 
+TEST_F(NamespaceEndCommentsFixerTest, IsFormatted) {
+  auto Style = getLLVMStyle();
+  Style.NamespaceMacros.push_back("SUITE");
+  EXPECT_TRUE(isFormatted("SUITE(\"foo\") {\n"
+                          "int i;\n"
+                          "int j;\n"
+                          "} // SUITE(\"foo\")",
+                          Style));
+}
+
 TEST_F(NamespaceEndCommentsFixerTest, AddsEndComment) {
   EXPECT_EQ("namespace {\n"
             "int i;\n"