CreateExpect: shouldn't generate expect declaration from actual function with default implementation from interface

#KT-32737 Fixed

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

@@ -30,11 +30,13 @@ import org.jetbrains.kotlin.idea.quickfix.TypeAccessibilityChecker
 import org.jetbrains.kotlin.idea.refactoring.createKotlinFile
 import org.jetbrains.kotlin.idea.refactoring.fqName.fqName
 import org.jetbrains.kotlin.idea.refactoring.introduce.showErrorHint
+import org.jetbrains.kotlin.idea.refactoring.isInterfaceClass
 import org.jetbrains.kotlin.idea.util.*
 import org.jetbrains.kotlin.idea.util.application.runWriteAction
 import org.jetbrains.kotlin.lexer.KtTokens
 import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.psi.*
+import org.jetbrains.kotlin.psi.psiUtil.containingClassOrObject
 import org.jetbrains.kotlin.psi.psiUtil.hasActualModifier
 import org.jetbrains.kotlin.resolve.BindingContext
 import org.jetbrains.kotlin.resolve.checkers.ExpectedActualDeclarationChecker
@@ -389,6 +391,11 @@ fun TypeAccessibilityChecker.isCorrectAndHaveNonPrivateModifier(declaration: KtN
         return false
     }
 
+    if (declaration is KtFunction && declaration.hasBody() && declaration.containingClassOrObject?.isInterfaceClass() == true) {
+        if (showErrorHint) showInaccessibleDeclarationError(declaration, "The function declaration shouldn't have a default implementation")
+        return false
+    }
+
     if (!showErrorHint) return checkAccessibility(declaration)
 
     val types = incorrectTypes(declaration).ifEmpty { return true }

idea/testData/multiModuleQuickFix/createExpect/functionInInterface/common/My.kt

@@ -0,0 +1,3 @@
+// DISABLE-ERRORS
+
+expect interface My

idea/testData/multiModuleQuickFix/createExpect/functionInInterface/common/My.kt.after

@@ -0,0 +1,5 @@
+// DISABLE-ERRORS
+
+expect interface My {
+    fun foo(param: String)
+}

idea/testData/multiModuleQuickFix/createExpect/functionInInterface/jvm/My.kt

@@ -0,0 +1,6 @@
+// "Create expected function in common module testModule_Common" "true"
+// DISABLE-ERRORS
+
+actual interface My {
+    actual fun <caret>foo(param: String)
+}

idea/testData/multiModuleQuickFix/createExpect/functionInInterface/jvm/My.kt.after

@@ -0,0 +1,6 @@
+// "Create expected function in common module testModule_Common" "true"
+// DISABLE-ERRORS
+
+actual interface My {
+    actual fun <caret>foo(param: String)
+}

idea/testData/multiModuleQuickFix/createExpect/functionWithImplementationInInterface/common/My.kt

@@ -0,0 +1,3 @@
+// DISABLE-ERRORS
+
+expect interface My

idea/testData/multiModuleQuickFix/createExpect/functionWithImplementationInInterface/common/My.kt.after

@@ -0,0 +1,3 @@
+// DISABLE-ERRORS
+
+expect interface My

idea/testData/multiModuleQuickFix/createExpect/functionWithImplementationInInterface/jvm/My.kt

@@ -0,0 +1,7 @@
+// "Create expected function in common module testModule_Common" "true"
+// SHOULD_FAIL_WITH: "The function declaration shouldn't have a default implementation"
+// DISABLE-ERRORS
+
+actual interface My {
+    actual fun <caret>foo(param: String) = param.length
+}

idea/testData/multiModuleQuickFix/createExpect/functionWithImplementationInInterface/jvm/My.kt.after

@@ -0,0 +1,7 @@
+// "Create expected function in common module testModule_Common" "true"
+// SHOULD_FAIL_WITH: "The function declaration shouldn't have a default implementation"
+// DISABLE-ERRORS
+
+actual interface My {
+    actual fun <caret>foo(param: String) = param.length
+}

idea/testData/multiModuleQuickFix/createExpect/functionWithImplementationInInterface2/common/My.kt

@@ -0,0 +1,3 @@
+// DISABLE-ERRORS
+
+expect interface My

idea/testData/multiModuleQuickFix/createExpect/functionWithImplementationInInterface2/common/My.kt.after

@@ -0,0 +1,3 @@
+// DISABLE-ERRORS
+
+expect interface My

idea/testData/multiModuleQuickFix/createExpect/functionWithImplementationInInterface2/jvm/My.kt

@@ -0,0 +1,9 @@
+// "Create expected function in common module testModule_Common" "true"
+// SHOULD_FAIL_WITH: "The function declaration shouldn't have a default implementation"
+// DISABLE-ERRORS
+
+actual interface My {
+    actual fun <caret>foo(param: String) {
+
+    }
+}

idea/testData/multiModuleQuickFix/createExpect/functionWithImplementationInInterface2/jvm/My.kt.after

@@ -0,0 +1,9 @@
+// "Create expected function in common module testModule_Common" "true"
+// SHOULD_FAIL_WITH: "The function declaration shouldn't have a default implementation"
+// DISABLE-ERRORS
+
+actual interface My {
+    actual fun <caret>foo(param: String) {
+
+    }
+}

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

@@ -553,6 +553,21 @@ public class QuickFixMultiModuleTestGenerated extends AbstractQuickFixMultiModul
             runTest("idea/testData/multiModuleQuickFix/createExpect/function2/");
         }
 
+        @TestMetadata("functionInInterface")
+        public void testFunctionInInterface() throws Exception {
+            runTest("idea/testData/multiModuleQuickFix/createExpect/functionInInterface/");
+        }
+
+        @TestMetadata("functionWithImplementationInInterface")
+        public void testFunctionWithImplementationInInterface() throws Exception {
+            runTest("idea/testData/multiModuleQuickFix/createExpect/functionWithImplementationInInterface/");
+        }
+
+        @TestMetadata("functionWithImplementationInInterface2")
+        public void testFunctionWithImplementationInInterface2() throws Exception {
+            runTest("idea/testData/multiModuleQuickFix/createExpect/functionWithImplementationInInterface2/");
+        }
+
         @TestMetadata("inlineClass")
         public void testInlineClass() throws Exception {
             runTest("idea/testData/multiModuleQuickFix/createExpect/inlineClass/");