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 4e3af45334d..5ff6656e5ab 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
@@ -194,26 +194,31 @@ abstract class BaseGradleIT {
     fun CompiledProject.assertSameFiles(expected: Iterable<String>, actual: Iterable<String>, messagePrefix: String = ""): CompiledProject {
         val expectedSet = expected.toSortedSet()
         val actualSet = actual.toSortedSet()
-        assertTrue(actualSet == expectedSet, messagePrefix + "expected files: ${expectedSet.joinToString()}\n  actual files: ${actualSet.joinToString()}")
+        assertTrue(actualSet == expectedSet, messagePrefix + "expected files: ${expectedSet.joinToString()}\n  != actual files: ${actualSet.joinToString()}")
         return this
     }
 
     fun CompiledProject.assertContainFiles(expected: Iterable<String>, actual: Iterable<String>, messagePrefix: String = ""): CompiledProject {
-        val expectedSet = expected.toSortedSet()
-        assertTrue(expectedSet.containsAll(actual.toList()), messagePrefix + "expected files: ${expectedSet.joinToString()}\n  actual files: ${actual.toSortedSet().joinToString()}")
+        val actualSet = actual.toSortedSet()
+        assertTrue(actualSet.containsAll(expected.toList()), messagePrefix + "expected files: ${expected.toSortedSet().joinToString()}\n  !in actual files: ${actualSet.joinToString()}")
         return this
     }
 
-    fun CompiledProject.assertCompiledKotlinSources(sources: Iterable<String>): CompiledProject = assertSameFiles(sources, compiledKotlinSources.projectRelativePaths(this.project), "Compiled Kotlin files differ:\n  ")
-    fun CompiledProject.assertCompiledKotlinSources(vararg sources: String): CompiledProject = assertCompiledKotlinSources(sources.asIterable())
+    fun CompiledProject.assertCompiledKotlinSources(sources: Iterable<String>, weakTesting: Boolean = false): CompiledProject =
+            if (weakTesting)
+                assertContainFiles(sources, compiledKotlinSources.projectRelativePaths(this.project), "Compiled Kotlin files differ:\n  ")
+            else
+                assertSameFiles(sources, compiledKotlinSources.projectRelativePaths(this.project), "Compiled Kotlin files differ:\n  ")
 
-    fun CompiledProject.assertCompiledKotlinSourcesContain(vararg sources: String): CompiledProject = assertContainFiles(sources.asIterable(), compiledKotlinSources.projectRelativePaths(this.project), "Compiled Kotlin files differ:\n  ")
+    fun CompiledProject.assertCompiledKotlinSources(vararg sources: String, weakTesting: Boolean = false): CompiledProject = assertCompiledKotlinSources(sources.asIterable(), weakTesting)
 
-    fun CompiledProject.assertCompiledJavaSources(sources: Iterable<String>): CompiledProject = assertSameFiles(sources, compiledJavaSources.projectRelativePaths(this.project), "Compiled Java files differ:\n  ")
-    fun CompiledProject.assertCompiledJavaSources(vararg sources: String): CompiledProject = assertCompiledJavaSources(sources.asIterable())
-
-    fun CompiledProject.assertCompiledJavaSourcesContain(vararg sources: String): CompiledProject = assertContainFiles(sources.asIterable(), compiledJavaSources.projectRelativePaths(this.project), "Compiled Java files differ:\n  ")
+    fun CompiledProject.assertCompiledJavaSources(sources: Iterable<String>, weakTesting: Boolean = false): CompiledProject =
+            if (weakTesting)
+                assertContainFiles(sources, compiledJavaSources.projectRelativePaths(this.project), "Compiled Java files differ:\n  ")
+            else
+                assertSameFiles(sources, compiledJavaSources.projectRelativePaths(this.project), "Compiled Java files differ:\n  ")
 
+    fun CompiledProject.assertCompiledJavaSources(vararg sources: String, weakTesting: Boolean = false): CompiledProject = assertCompiledJavaSources(sources.asIterable(), weakTesting)
 
     private fun Project.createBuildCommand(params: Array<out String>, options: BuildOptions): List<String> =
             createGradleCommand(createGradleTailParameters(options, params))
diff --git a/libraries/tools/kotlin-gradle-plugin/src/test/kotlin/org/jetbrains/kotlin/gradle/BaseIncrementalGradleIT.kt b/libraries/tools/kotlin-gradle-plugin/src/test/kotlin/org/jetbrains/kotlin/gradle/BaseIncrementalGradleIT.kt
index d8a42f38f0f..a20ce17a412 100644
--- a/libraries/tools/kotlin-gradle-plugin/src/test/kotlin/org/jetbrains/kotlin/gradle/BaseIncrementalGradleIT.kt
+++ b/libraries/tools/kotlin-gradle-plugin/src/test/kotlin/org/jetbrains/kotlin/gradle/BaseIncrementalGradleIT.kt
@@ -134,7 +134,7 @@ dependencies {
     }
 
 
-    fun IncrementalTestProject.performAndAssertBuildStages(options: BuildOptions = defaultBuildOptions()) {
+    fun IncrementalTestProject.performAndAssertBuildStages(options: BuildOptions = defaultBuildOptions(), weakTesting: Boolean = false) {
 
         val checkKnown = testIsKnownJpsTestProject(resourcesRoot)
         Assume.assumeTrue(checkKnown.second ?: "", checkKnown.first)
@@ -157,22 +157,22 @@ dependencies {
 
         if (buildLog.size == 1) {
             modify()
-            buildAndAssertStageResults(buildLog.first())
+            buildAndAssertStageResults(buildLog.first(), weakTesting = weakTesting)
         }
         else {
             buildLog.forEachIndexed { stage, stageResults ->
                 modify(stage + 1)
-                buildAndAssertStageResults(stageResults)
+                buildAndAssertStageResults(stageResults, weakTesting = weakTesting)
             }
         }
     }
 
-    fun IncrementalTestProject.buildAndAssertStageResults(expected: StageResults, options: BuildOptions = defaultBuildOptions()) {
+    fun IncrementalTestProject.buildAndAssertStageResults(expected: StageResults, options: BuildOptions = defaultBuildOptions(), weakTesting: Boolean = false) {
         build("build", options = options) {
             if (expected.compileSucceeded) {
                 assertSuccessful()
-                assertCompiledJavaSources(expected.compiledJavaFiles)
-                assertCompiledKotlinSources(expected.compiledKotlinFiles)
+                assertCompiledJavaSources(expected.compiledJavaFiles, weakTesting)
+                assertCompiledKotlinSources(expected.compiledKotlinFiles, weakTesting)
             }
             else {
                 assertFailed()
diff --git a/libraries/tools/kotlin-gradle-plugin/src/test/kotlin/org/jetbrains/kotlin/gradle/KotlinGradlePluginParametrizedIT.kt b/libraries/tools/kotlin-gradle-plugin/src/test/kotlin/org/jetbrains/kotlin/gradle/KotlinGradlePluginParametrizedIT.kt
index 979252535dc..405dad3c1f8 100644
--- a/libraries/tools/kotlin-gradle-plugin/src/test/kotlin/org/jetbrains/kotlin/gradle/KotlinGradlePluginParametrizedIT.kt
+++ b/libraries/tools/kotlin-gradle-plugin/src/test/kotlin/org/jetbrains/kotlin/gradle/KotlinGradlePluginParametrizedIT.kt
@@ -17,7 +17,7 @@ class KotlinGradlePluginJpsParametrizedIT : BaseIncrementalGradleIT() {
     @Test
     fun testFromJps() {
         try {
-            JpsTestProject(jpsResourcesPath, relativePath).performAndAssertBuildStages()
+            JpsTestProject(jpsResourcesPath, relativePath).performAndAssertBuildStages(weakTesting = true)
         }
         finally {
             if (defaultBuildOptions().withDaemon)