Implement members: implement functions in the same order as within Java interface

#KT-31760 Fixed

core/descriptors.jvm/src/org/jetbrains/kotlin/load/java/lazy/descriptors/LazyJavaClassMemberScope.kt

@@ -75,7 +75,7 @@ class LazyJavaClassMemberScope(
     override fun computeMemberIndex() = ClassDeclaredMemberIndex(jClass) { !it.isStatic }
 
     override fun computeFunctionNames(kindFilter: DescriptorKindFilter, nameFilter: ((Name) -> Boolean)?) =
-        ownerDescriptor.typeConstructor.supertypes.flatMapTo(hashSetOf()) {
+        ownerDescriptor.typeConstructor.supertypes.flatMapTo(linkedSetOf()) {
             it.memberScope.getFunctionNames()
         }.apply {
             addAll(declaredMemberIndex().getMethodNames())

idea/testData/codeInsight/overrideImplement/javaInterfaceMethodInCorrectOrder/foo/Impl.kt

@@ -0,0 +1,4 @@
+package foo
+
+class <caret>Impl : TestJavaInterface {
+}

idea/testData/codeInsight/overrideImplement/javaInterfaceMethodInCorrectOrder/foo/Impl.kt.after

@@ -0,0 +1,27 @@
+package foo
+
+class Impl : TestJavaInterface {
+    override fun onTextEvent() {
+        TODO("Not yet implemented")
+    }
+
+    override fun onAttachmentEvent() {
+        TODO("Not yet implemented")
+    }
+
+    override fun onEventDeleted() {
+        TODO("Not yet implemented")
+    }
+
+    override fun onSeenReceipt() {
+        TODO("Not yet implemented")
+    }
+
+    override fun onDeliveredReceipt() {
+        TODO("Not yet implemented")
+    }
+
+    override fun onTypingEvent() {
+        TODO("Not yet implemented")
+    }
+}

idea/testData/codeInsight/overrideImplement/javaInterfaceMethodInCorrectOrder/foo/TestJavaInterface.java

@@ -0,0 +1,15 @@
+package foo;
+
+public interface TestJavaInterface {
+    void onTextEvent();
+
+    void onAttachmentEvent();
+
+    void onEventDeleted();
+
+    void onSeenReceipt();
+
+    void onDeliveredReceipt();
+
+    void onTypingEvent();
+}

idea/tests/org/jetbrains/kotlin/idea/codeInsight/AbstractOverrideImplementTest.kt

@@ -63,6 +63,10 @@ abstract class AbstractOverrideImplementTest : KotlinLightCodeInsightFixtureTest
         doDirectoryTest(OverrideMembersHandler(), memberToImplement)
     }
 
+    protected fun doMultiImplementDirectoryTest() {
+        doMultiDirectoryTest(ImplementMembersHandler())
+    }
+
     protected fun doMultiOverrideDirectoryTest() {
         doMultiDirectoryTest(OverrideMembersHandler())
     }

idea/tests/org/jetbrains/kotlin/idea/codeInsight/OverrideImplementTest.kt

@@ -45,6 +45,10 @@ class OverrideImplementTest : AbstractOverrideImplementTest() {
         doImplementDirectoryTest()
     }
 
+    fun testJavaInterfaceMethodInCorrectOrder() {
+        doMultiImplementDirectoryTest()
+    }
+
     fun testJavaParameters() {
         doImplementDirectoryTest()
     }