Expand "Create expected..." also to a members if an expect class doesn't exist

#KT-31272 Fixed

idea/src/org/jetbrains/kotlin/idea/quickfix/expectactual/CreateExpectedFix.kt

@@ -74,27 +74,39 @@ sealed class CreateExpectedFix<D : KtNamedDeclaration>(
             // For function we allow it, because overloads are possible
             if (compatibility.isNotEmpty() && declaration !is KtFunction) return emptyList()
 
-            val containingClass = declaration.containingClassOrObject
-            val expectedContainingClass = containingClass?.liftToExpected() as? KtClassOrObject
-            if (containingClass != null && expectedContainingClass == null) {
-                // In this case fix should be invoked on containingClass
-                return emptyList()
-            }
+            val (actualDeclaration, expectedContainingClass) = findFirstActualWithExpectedClass(declaration)
+            if (compatibility.isNotEmpty() && actualDeclaration !is KtFunction) return emptyList()
+
             // If there is already an expected class, we suggest only for its module,
             // otherwise we suggest for all relevant expected modules
             val expectedModules = expectedContainingClass?.module?.let { listOf(it) }
-                ?: declaration.module?.implementedModules
+                ?: actualDeclaration.module?.implementedModules
                 ?: return emptyList()
-            return when (declaration) {
-                is KtClassOrObject -> expectedModules.map { CreateExpectedClassFix(declaration, expectedContainingClass, it) }
-                is KtFunction -> expectedModules.map { CreateExpectedFunctionFix(declaration, expectedContainingClass, it) }
-                is KtProperty, is KtParameter -> expectedModules.map { CreateExpectedPropertyFix(declaration, expectedContainingClass, it) }
+            return when (actualDeclaration) {
+                is KtClassOrObject -> expectedModules.map { CreateExpectedClassFix(actualDeclaration, expectedContainingClass, it) }
+                is KtFunction -> expectedModules.map { CreateExpectedFunctionFix(actualDeclaration, expectedContainingClass, it) }
+                is KtProperty, is KtParameter -> expectedModules.map {
+                    CreateExpectedPropertyFix(
+                        actualDeclaration,
+                        expectedContainingClass,
+                        it
+                    )
+                }
                 else -> emptyList()
             }
         }
     }
 }
 
+private tailrec fun findFirstActualWithExpectedClass(declaration: KtNamedDeclaration): Pair<KtNamedDeclaration, KtClassOrObject?> {
+    val containingClass = declaration.containingClassOrObject
+    val expectedContainingClass = containingClass?.liftToExpected() as? KtClassOrObject
+    return if (containingClass != null && expectedContainingClass == null)
+        findFirstActualWithExpectedClass(containingClass)
+    else
+        declaration to expectedContainingClass
+}
+
 class CreateExpectedClassFix(
     klass: KtClassOrObject,
     outerExpectedClass: KtClassOrObject?,

idea/testData/multiModuleQuickFix/expectClassNoAccessOnMember/jvm/My.kt

@@ -1,6 +1,7 @@
 // "Create expected function in common module testModule_Common" "false"
 // ACTION: Convert member to extension
 // ACTION: Convert to block body
+// ACTION: Create expected class in common module testModule_Common
 // ACTION: Move to companion object
 // ACTION: Remove 'actual' modifier
 // ACTION: Remove explicit type specification

idea/testData/multiModuleQuickFix/expectClassOnMember/header/My.kt.after

@@ -0,0 +1,11 @@
+expect class <caret>My {
+    fun foo(param: String): Int
+    fun String.bar(y: Double): Boolean
+    fun baz()
+
+    constructor(flag: Boolean)
+
+    val isGood: Boolean
+    var status: Int
+
+}

idea/testData/multiModuleQuickFix/expectClassOnMember/jvm/My.kt

@@ -0,0 +1,19 @@
+// "Create expected class in common module testModule_Common" "true"
+// DISABLE-ERRORS
+
+actual class My {
+    actual fun <caret>foo(param: String): Int = 42
+
+    actual fun String.bar(y: Double): Boolean = true
+
+    actual fun baz() {}
+
+    actual constructor(flag: Boolean) {}
+
+    actual val isGood: Boolean
+        get() = true
+    actual var status: Int
+        get() = 0
+        set(value) {}
+
+}

idea/testData/multiModuleQuickFix/expectClassOnMember/jvm/My.kt.after

@@ -0,0 +1,19 @@
+// "Create expected class in common module testModule_Common" "true"
+// DISABLE-ERRORS
+
+actual class My {
+    actual fun <caret>foo(param: String): Int = 42
+
+    actual fun String.bar(y: Double): Boolean = true
+
+    actual fun baz() {}
+
+    actual constructor(flag: Boolean) {}
+
+    actual val isGood: Boolean
+        get() = true
+    actual var status: Int
+        get() = 0
+        set(value) {}
+
+}

idea/tests/org/jetbrains/kotlin/idea/quickfix/QuickFixMultiModuleTestGenerated.java

@@ -299,6 +299,11 @@ public class QuickFixMultiModuleTestGenerated extends AbstractQuickFixMultiModul
         runTest("idea/testData/multiModuleQuickFix/expectClassNoAccessOnMember/");
     }
 
+    @TestMetadata("expectClassOnMember")
+    public void testExpectClassOnMember() throws Exception {
+        runTest("idea/testData/multiModuleQuickFix/expectClassOnMember/");
+    }
+
     @TestMetadata("expectClassProperty")
     public void testExpectClassProperty() throws Exception {
         runTest("idea/testData/multiModuleQuickFix/expectClassProperty/");