Override/Implement: Do not generate bodies for header class members

#KT-15659 Fixed

idea/idea-completion/src/org/jetbrains/kotlin/idea/completion/OverridesCompletion.kt

@@ -119,7 +119,7 @@ class OverridesCompletion(
                     // keep original modifiers
                     val modifierList = KtPsiFactory(context.project).createModifierList(dummyMember.modifierList!!.text)
 
-                    val prototype = memberObject.generateMember(context.project, false)
+                    val prototype = memberObject.generateMember(classOrObject, false)
                     prototype.modifierList!!.replace(modifierList)
                     val insertedMember = dummyMember.replaced(prototype)
 

idea/idea-core/src/org/jetbrains/kotlin/idea/core/overrideImplement/OverrideImplementMembersHandler.kt

@@ -106,8 +106,7 @@ abstract class OverrideImplementMembersHandler : LanguageCodeInsightActionHandle
                 selectedElements: Collection<OverrideMemberChooserObject>,
                 copyDoc: Boolean
         ) {
-            val project = classOrObject.project
+            insertMembersAfter(editor, classOrObject, selectedElements.map { it.generateMember(classOrObject, copyDoc) })
-            insertMembersAfter(editor, classOrObject, selectedElements.map { it.generateMember(project, copyDoc) })
         }
     }
 }

idea/idea-core/src/org/jetbrains/kotlin/idea/core/overrideImplement/OverrideMemberChooserObject.kt

@@ -32,6 +32,7 @@ import org.jetbrains.kotlin.idea.j2k.IdeaDocCommentConverter
 import org.jetbrains.kotlin.idea.kdoc.KDocElementFactory
 import org.jetbrains.kotlin.idea.util.IdeDescriptorRenderers
 import org.jetbrains.kotlin.idea.util.approximateFlexibleTypes
+import org.jetbrains.kotlin.lexer.KtTokens
 import org.jetbrains.kotlin.psi.*
 import org.jetbrains.kotlin.psi.findDocComment.findDocComment
 import org.jetbrains.kotlin.renderer.*
@@ -95,7 +96,11 @@ interface OverrideMemberChooserObject : ClassMember {
     }
 }
 
-fun OverrideMemberChooserObject.generateMember(project: Project, copyDoc: Boolean): KtCallableDeclaration {
+fun OverrideMemberChooserObject.generateMember(targetClass: KtClassOrObject, copyDoc: Boolean): KtCallableDeclaration {
+    val project = targetClass.project
+
+    val bodyType = if (targetClass.hasModifier(KtTokens.HEADER_KEYWORD)) OverrideMemberChooserObject.BodyType.NO_BODY else bodyType
+
     val descriptor = immediateSuper
     if (preferConstructorParameter && descriptor is PropertyDescriptor) return generateConstructorParameter(project, descriptor)
 

idea/src/org/jetbrains/kotlin/idea/actions/generate/KotlinGenerateEqualsAndHashcodeAction.kt

@@ -164,7 +164,7 @@ class KotlinGenerateEqualsAndHashcodeAction : KotlinGenerateMemberActionBase<Kot
             if (!needEquals) return null
 
             val superEquals = classDescriptor.getSuperClassOrAny().findDeclaredEquals(true)!!
-            val equalsFun = generateFunctionSkeleton(superEquals, project)
+            val equalsFun = generateFunctionSkeleton(superEquals, targetClass)
 
             val paramName = equalsFun.valueParameters.first().name!!.quoteIfNeeded()
             var typeForCast = IdeDescriptorRenderers.SOURCE_CODE.renderClassifierName(classDescriptor)
@@ -249,7 +249,7 @@ class KotlinGenerateEqualsAndHashcodeAction : KotlinGenerateMemberActionBase<Kot
             if (!needHashCode) return null
 
             val superHashCode = classDescriptor.getSuperClassOrAny().findDeclaredHashCode(true)!!
-            val hashCodeFun = generateFunctionSkeleton(superHashCode, project)
+            val hashCodeFun = generateFunctionSkeleton(superHashCode, targetClass)
             val builtins = superHashCode.builtIns
 
             val propertyIterator = variablesForHashCode.iterator()

idea/src/org/jetbrains/kotlin/idea/actions/generate/KotlinGenerateToStringAction.kt

@@ -178,16 +178,16 @@ class KotlinGenerateToStringAction : KotlinGenerateMemberActionBase<KotlinGenera
                     project)
     }
 
-    private fun generateToString(project: Project, info: Info): KtNamedFunction? {
+    private fun generateToString(targetClass: KtClassOrObject, info: Info): KtNamedFunction? {
         val superToString = info.classDescriptor.getSuperClassOrAny().findDeclaredToString(true)!!
-        return generateFunctionSkeleton(superToString, project).apply {
+        return generateFunctionSkeleton(superToString, targetClass).apply {
-            bodyExpression!!.replace(KtPsiFactory(project).createExpression("{\n${info.generator.generate(info)}\n}"))
+            bodyExpression!!.replace(KtPsiFactory(targetClass).createExpression("{\n${info.generator.generate(info)}\n}"))
         }
     }
 
     override fun generateMembers(project: Project, editor: Editor?, info: Info): List<KtDeclaration> {
         val targetClass = info.classDescriptor.source.getPsi() as KtClass
-        val prototype = generateToString(project, info) ?: return emptyList()
+        val prototype = generateToString(targetClass, info) ?: return emptyList()
         val anchor = with(targetClass.declarations) { lastIsInstanceOrNull<KtNamedFunction>() ?: lastOrNull() }
         return insertMembersAfter(editor, targetClass, listOf(prototype), anchor)
     }

idea/src/org/jetbrains/kotlin/idea/actions/generate/utils.kt

@@ -79,8 +79,8 @@ fun confirmMemberRewrite(targetClass: KtClass, vararg descriptors: FunctionDescr
                                     Messages.getQuestionIcon()) == Messages.YES
 }
 
-fun generateFunctionSkeleton(descriptor: FunctionDescriptor, project: Project): KtNamedFunction {
+fun generateFunctionSkeleton(descriptor: FunctionDescriptor, targetClass: KtClassOrObject): KtNamedFunction {
     return OverrideMemberChooserObject
-            .create(project, descriptor, descriptor, OverrideMemberChooserObject.BodyType.EMPTY)
+            .create(targetClass.project, descriptor, descriptor, OverrideMemberChooserObject.BodyType.EMPTY)
-            .generateMember(project, false) as KtNamedFunction
+            .generateMember(targetClass, false) as KtNamedFunction
 }

idea/src/org/jetbrains/kotlin/idea/quickfix/SpecifyOverrideExplicitlyFix.kt

@@ -82,7 +82,7 @@ class SpecifyOverrideExplicitlyFix(
                         project, delegatedDescriptor, overriddenDescriptor,
                         OverrideMemberChooserObject.BodyType.Delegate(delegateTargetDescriptor.name.asString())
                 )
-                val member = overrideMemberChooserObject.generateMember(project, copyDoc = false)
+                val member = overrideMemberChooserObject.generateMember(element, copyDoc = false)
                 val insertedMember = element.addDeclaration(member)
                 ShortenReferences.DEFAULT.process(insertedMember)
                 return

idea/testData/multiModuleQuickFix/implementMembersInHeaderClass/header/header.kt

@@ -0,0 +1,8 @@
+// "Implement members" "true"
+// DISABLE-ERRORS
+
+interface I {
+    fun foo()
+}
+
+header class <caret>Bar : I

idea/testData/multiModuleQuickFix/implementMembersInHeaderClass/header/header.kt.after

@@ -0,0 +1,10 @@
+// "Implement members" "true"
+// DISABLE-ERRORS
+
+interface I {
+    fun foo()
+}
+
+header class <caret>Bar : I {
+    override fun foo()
+}

idea/tests/org/jetbrains/kotlin/idea/quickfix/QuickFixMultiModuleTest.kt

@@ -153,4 +153,7 @@ class QuickFixMultiModuleTest : AbstractQuickFixMultiModuleTest() {
 
     @Test
     fun testFunctionTypeReceiverToParameterByImpl() = doTestHeaderWithJvmAndJs()
+
+    @Test
+    fun testImplementMembersInHeaderClass() = doMultiPlatformTest(impls = *arrayOf())
 }