diff --git a/clang-tools-extra/unittests/clang-tidy/ModernizeModuleTest.cpp b/clang-tools-extra/unittests/clang-tidy/ModernizeModuleTest.cpp
index 65bf0691372c..b772c0054de4 100644
--- a/clang-tools-extra/unittests/clang-tidy/ModernizeModuleTest.cpp
+++ b/clang-tools-extra/unittests/clang-tidy/ModernizeModuleTest.cpp
@@ -48,6 +48,11 @@ namespace {
 struct Param {
   bool Matched;
   const char *Text;
+
+  friend std::ostream &operator<<(std::ostream &Str, const Param &Value) {
+    return Str << "Matched: " << std::boolalpha << Value.Matched << ", Text: '"
+               << Value.Text << "'";
+  }
 };
 
 class MatcherTest : public ::testing::TestWithParam<Param> {};