Fix class run configuration applicability (KT-33787)

The bug appeared when we turned “ultra light classes” on by default.
  The difference with the old implementation is that
  PsiClass.getTextRange() returns the correct non-null value.
  This triggers JavaExecutionUtil#stepIntoSingleClass() to return
  a light class instead of the original location (of a PsiIdentifier).
  So AbstractJavaTestConfigurationProducer#isConfigurationFromContext()
  returns true, and the wrong configuration is reused instead of
  creating the new one.

By the way, for Java it also returns an identifier because of the
  PsiTreeUtil.getParentOfType(element, PsiClass.class) != null check.

The proper fix should land in the newer versions of IDEA, however this
  (hopefully, temporary) hack will fix test method gutters for
  all platform versions.

compiler/light-classes/src/org/jetbrains/kotlin/asJava/classes/KtLightClassForSourceDeclaration.kt

@@ -81,7 +81,7 @@ abstract class KtLightClassForSourceDeclaration(
 
     override fun getText() = kotlinOrigin.text ?: ""
 
-    override fun getTextRange(): TextRange = kotlinOrigin.textRange ?: TextRange.EMPTY_RANGE
+    override fun getTextRange(): TextRange? = kotlinOrigin.textRange ?: TextRange.EMPTY_RANGE
 
     override fun getTextOffset() = kotlinOrigin.textOffset
 

compiler/light-classes/src/org/jetbrains/kotlin/asJava/classes/ultraLightClass.kt

@@ -5,6 +5,8 @@
 
 package org.jetbrains.kotlin.asJava.classes
 
+import com.intellij.openapi.util.TextRange
+import com.intellij.openapi.util.registry.Registry
 import com.intellij.psi.*
 import com.intellij.psi.impl.InheritanceImplUtil
 import com.intellij.psi.impl.PsiClassImplUtil
@@ -475,4 +477,12 @@ open class KtUltraLightClass(classOrObject: KtClassOrObject, internal val suppor
     override fun isDeprecated(): Boolean = _deprecated
 
     override fun copy(): KtLightClassImpl = KtUltraLightClass(classOrObject.copy() as KtClassOrObject, support)
+
+    override fun getTextRange(): TextRange? {
+        if (Registry.`is`("kotlin.ultra.light.classes.empty.text.range", true)) {
+            return null
+        }
+
+        return super.getTextRange()
+    }
 }

idea/idea-gradle/tests/org/jetbrains/kotlin/idea/codeInsight/gradle/GradleTestRunConfigurationCustomTest.kt

@@ -34,20 +34,20 @@ class GradleTestRunConfigurationCustomTest : GradleImportingTestCase() {
                 val kotlinFile = files.first { it.name == "MyKotlinTest.kt" }
 
                 val javaClassConfiguration = getConfiguration(javaFile, myProject, "MyTest")
-                javaClassConfiguration.isProducedBy(TestClassGradleConfigurationProducer::class.java)
+                assert(javaClassConfiguration.isProducedBy(TestClassGradleConfigurationProducer::class.java))
-                assert(javaClassConfiguration.configuration !is KotlinGradleRunConfiguration)
+                assert(javaClassConfiguration.configuration.name == "MyTest")
 
                 val javaMethodConfiguration = getConfiguration(javaFile, myProject, "testA")
-                javaMethodConfiguration.isProducedBy(TestMethodGradleConfigurationProducer::class.java)
+                assert(javaMethodConfiguration.isProducedBy(TestMethodGradleConfigurationProducer::class.java))
-                assert(javaMethodConfiguration.configuration !is KotlinGradleRunConfiguration)
+                assert(javaMethodConfiguration.configuration.name == "MyTest.testA")
 
                 val kotlinClassConfiguration = getConfiguration(kotlinFile, myProject, "MyKotlinTest")
-                kotlinClassConfiguration.isProducedBy(KotlinJvmTestClassGradleConfigurationProducer::class.java)
+                assert(kotlinClassConfiguration.isProducedBy(KotlinJvmTestClassGradleConfigurationProducer::class.java))
-                assert(kotlinClassConfiguration.configuration is KotlinGradleRunConfiguration)
+                assert(kotlinClassConfiguration.configuration.name == "MyKotlinTest")
 
                 val kotlinFunctionConfiguration = getConfiguration(kotlinFile, myProject, "testA")
-                kotlinFunctionConfiguration.isProducedBy(KotlinJvmTestMethodGradleConfigurationProducer::class.java)
+                assert(kotlinFunctionConfiguration.isProducedBy(KotlinJvmTestMethodGradleConfigurationProducer::class.java))
-                assert(kotlinFunctionConfiguration.configuration is KotlinGradleRunConfiguration)
+                assert(kotlinFunctionConfiguration.configuration.name == "MyKotlinTest.testA")
             }
         }
     }

idea/resources/META-INF/jvm.xml

@@ -175,6 +175,11 @@
                    defaultValue="true"
                    restartRequired="false"/>
 
+      <registryKey key="kotlin.ultra.light.classes.empty.text.range"
+                   description="Return 'null' text range as in old light class implementation"
+                   defaultValue="true"
+                   restartRequired="false"/>
+
       <registryKey key="kotlin.uast.force.uinjectionhost"
                    description="Whether to convert `KtStringTemplateExpression` to `KotlinStringTemplateUPolyadicExpression` in all cases"
                    defaultValue="true"

idea/tests/org/jetbrains/kotlin/asJava/LightClassFromTextTest.kt

@@ -43,7 +43,7 @@ class LightClassFromTextTest : KotlinLightCodeInsightFixtureTestCase() {
         val classC = classes[0]
         assertEquals("C", classC.qualifiedName)
         assertEquals("class C", classC.text)
-        assertEquals(TextRange(17, 24), classC.textRange)
+        assertEquals(null, classC.textRange)
         assertEquals(23, classC.textOffset)
         assertEquals(17, classC.startOffsetInParent)
         assertTrue(classC.isWritable)

idea/tests/org/jetbrains/kotlin/idea/run/KotlinJUnitRunConfigurationTest.kt

@@ -44,20 +44,20 @@ class KotlinJUnitRunConfigurationTest : AbstractRunConfigurationTest() {
             val kotlinFile = testDir.findChild("MyKotlinTest.kt")!!
 
             val javaClassConfiguration = getConfiguration(javaFile, project, "MyTest")
-            javaClassConfiguration.isProducedBy(TestInClassConfigurationProducer::class.java)
+            assert(javaClassConfiguration.isProducedBy(TestInClassConfigurationProducer::class.java))
-            assert(javaClassConfiguration.configuration !is KotlinJUnitConfiguration)
+            assert(javaClassConfiguration.configuration.name == "MyJavaTest")
 
             val javaMethodConfiguration = getConfiguration(javaFile, project, "testA")
-            javaMethodConfiguration.isProducedBy(TestInClassConfigurationProducer::class.java)
+            assert(javaMethodConfiguration.isProducedBy(TestInClassConfigurationProducer::class.java))
-            assert(javaMethodConfiguration.configuration !is KotlinJUnitConfiguration)
+            assert(javaMethodConfiguration.configuration.name == "MyJavaTest.testA")
 
             val kotlinClassConfiguration = getConfiguration(kotlinFile, project, "MyKotlinTest")
-            kotlinClassConfiguration.isProducedBy(KotlinJUnitRunConfigurationProducer::class.java)
+            assert(kotlinClassConfiguration.isProducedBy(KotlinJUnitRunConfigurationProducer::class.java))
-            assert(kotlinClassConfiguration.configuration is KotlinJUnitConfiguration)
+            assert(kotlinClassConfiguration.configuration.name == "MyKotlinTest")
 
             val kotlinFunctionConfiguration = getConfiguration(kotlinFile, project, "testA")
-            kotlinFunctionConfiguration.isProducedBy(KotlinJUnitRunConfigurationProducer::class.java)
+            assert(kotlinFunctionConfiguration.isProducedBy(KotlinJUnitRunConfigurationProducer::class.java))
-            assert(kotlinFunctionConfiguration.configuration is KotlinJUnitConfiguration)
+            assert(kotlinFunctionConfiguration.configuration.name == "MyKotlinTest.testA")
         } finally {
             detachJUnitLibrary()
         }