diff --git a/libraries/tools/kotlin-gradle-plugin/src/test/kotlin/org/jetbrains/kotlin/gradle/BaseGradleIT.kt b/libraries/tools/kotlin-gradle-plugin/src/test/kotlin/org/jetbrains/kotlin/gradle/BaseGradleIT.kt
index 2a348226ba5..7bc6bc616b9 100644
--- a/libraries/tools/kotlin-gradle-plugin/src/test/kotlin/org/jetbrains/kotlin/gradle/BaseGradleIT.kt
+++ b/libraries/tools/kotlin-gradle-plugin/src/test/kotlin/org/jetbrains/kotlin/gradle/BaseGradleIT.kt
@@ -127,14 +127,14 @@ abstract class BaseGradleIT {
 
     fun CompiledProject.assertContains(vararg expected: String): CompiledProject {
         for (str in expected) {
-            assertTrue(output.contains(str.normalize()), "Should contain '$str', actual output: $output")
+            assertTrue(output.contains(str.normalize()), "Output should contain '$str'")
         }
         return this
     }
 
     fun CompiledProject.assertNotContains(vararg expected: String): CompiledProject {
         for (str in expected) {
-            assertFalse(output.contains(str.normalize()), "Should not contain '$str', actual output: $output")
+            assertFalse(output.contains(str.normalize()), "Output should not contain '$str'")
         }
         return this
     }