1 files changed, 27 insertions, 0 deletions
diff --git a/clang/unittests/Tooling/ToolingTest.cpp b/clang/unittests/Tooling/ToolingTest.cpp
index 34f68a6aeb6..f9f4de3d9a1 100644
--- a/clang/unittests/Tooling/ToolingTest.cpp
+++ b/clang/unittests/Tooling/ToolingTest.cpp
@@ -400,6 +400,33 @@ TEST(ClangToolTest, ArgumentAdjusters) {
   EXPECT_FALSE(Found);
 }
 
+TEST(ClangToolTest, NoDoubleSyntaxOnly) {
+  FixedCompilationDatabase Compilations("/", {"-fsyntax-only"});
+
+  ClangTool Tool(Compilations, std::vector<std::string>(1, "/a.cc"));
+  Tool.mapVirtualFile("/a.cc", "void a() {}");
+
+  std::unique_ptr<FrontendActionFactory> Action(
+      newFrontendActionFactory<SyntaxOnlyAction>());
+
+  size_t SyntaxOnlyCount = 0;
+  ArgumentsAdjuster CheckSyntaxOnlyAdjuster =
+      [&SyntaxOnlyCount](const CommandLineArguments &Args,
+                         StringRef /*unused*/) {
+        for (llvm::StringRef Arg : Args) {
+          if (Arg == "-fsyntax-only")
+            ++SyntaxOnlyCount;
+        }
+        return Args;
+      };
+
+  Tool.clearArgumentsAdjusters();
+  Tool.appendArgumentsAdjuster(getClangSyntaxOnlyAdjuster());
+  Tool.appendArgumentsAdjuster(CheckSyntaxOnlyAdjuster);
+  Tool.run(Action.get());
+  EXPECT_EQ(SyntaxOnlyCount, 1U);
+}
+
 TEST(ClangToolTest, BaseVirtualFileSystemUsage) {
   FixedCompilationDatabase Compilations("/", std::vector<std::string>());
   llvm::IntrusiveRefCntPtr<llvm::vfs::OverlayFileSystem> OverlayFileSystem(