1 files changed, 33 insertions, 0 deletions
diff --git a/clang-tools-extra/unittests/clang-tidy/ClangTidyOptionsTest.cpp b/clang-tools-extra/unittests/clang-tidy/ClangTidyOptionsTest.cpp
index 5a7da5acce1..36105a24cba 100644
--- a/clang-tools-extra/unittests/clang-tidy/ClangTidyOptionsTest.cpp
+++ b/clang-tools-extra/unittests/clang-tidy/ClangTidyOptionsTest.cpp
@@ -1,5 +1,6 @@
 #include "ClangTidyOptions.h"
 #include "gtest/gtest.h"
+#include "llvm/ADT/StringExtras.h"
 
 namespace clang {
 namespace tidy {
@@ -66,6 +67,38 @@ TEST(ParseConfiguration, ValidConfiguration) {
   EXPECT_EQ("some.user", *Options->User);
 }
 
+TEST(ParseConfiguration, MergeConfigurations) {
+  llvm::ErrorOr<ClangTidyOptions> Options1 = parseConfiguration(R"(
+      Checks: "check1,check2"
+      HeaderFilterRegex: "filter1"
+      AnalyzeTemporaryDtors: true
+      User: user1
+      ExtraArgs: ['arg1', 'arg2']
+      ExtraArgsBefore: ['arg-before1', 'arg-before2']
+  )");
+  ASSERT_TRUE(!!Options1);
+  llvm::ErrorOr<ClangTidyOptions> Options2 = parseConfiguration(R"(
+      Checks: "check3,check4"
+      HeaderFilterRegex: "filter2"
+      AnalyzeTemporaryDtors: false
+      User: user2
+      ExtraArgs: ['arg3', 'arg4']
+      ExtraArgsBefore: ['arg-before3', 'arg-before4']
+  )");
+  ASSERT_TRUE(!!Options2);
+  ClangTidyOptions Options = Options1->mergeWith(*Options2);
+  EXPECT_EQ("check1,check2,check3,check4", *Options.Checks);
+  EXPECT_EQ("filter2", *Options.HeaderFilterRegex);
+  EXPECT_FALSE(*Options.AnalyzeTemporaryDtors);
+  EXPECT_EQ("user2", *Options.User);
+  ASSERT_TRUE(Options.ExtraArgs.hasValue());
+  EXPECT_EQ("arg1,arg2,arg3,arg4", llvm::join(Options.ExtraArgs->begin(),
+                                              Options.ExtraArgs->end(), ","));
+  ASSERT_TRUE(Options.ExtraArgsBefore.hasValue());
+  EXPECT_EQ("arg-before1,arg-before2,arg-before3,arg-before4",
+            llvm::join(Options.ExtraArgsBefore->begin(),
+                       Options.ExtraArgsBefore->end(), ","));
+}
 } // namespace test
 } // namespace tidy
 } // namespace clang