[FIR] ensure that status is resolved when we create fake overrides

We should create the fake override only when we
already have resolved status.

Otherwise, the fake override declaration will be created
with unresolved status, and its status will never be computed
as we do not resolve fake override declarations.

^KT-56543

compiler/fir/providers/src/org/jetbrains/kotlin/fir/scopes/impl/FirFakeOverrideGenerator.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2022 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Copyright 2010-2023 JetBrains s.r.o. and Kotlin Programming Language contributors.
  * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
  */
 
@@ -112,6 +112,8 @@ object FirFakeOverrideGenerator {
         newVisibility: Visibility? = null,
         fakeOverrideSubstitution: FakeOverrideSubstitution? = null
     ): FirSimpleFunction {
+        checkStatusIsResolved(baseFunction)
+
         return buildSimpleFunction {
             source = baseFunction.source
             moduleData = session.nullableModuleData ?: baseFunction.moduleData
@@ -147,6 +149,8 @@ object FirFakeOverrideGenerator {
         isExpect: Boolean,
         fakeOverrideSubstitution: FakeOverrideSubstitution?
     ): FirConstructor {
+        checkStatusIsResolved(baseConstructor)
+
         // TODO: consider using here some light-weight functions instead of pseudo-real FirMemberFunctionImpl
         // As second alternative, we can invent some light-weight kind of FirRegularClass
         return buildConstructor {
@@ -350,6 +354,8 @@ object FirFakeOverrideGenerator {
         newVisibility: Visibility? = null,
         fakeOverrideSubstitution: FakeOverrideSubstitution? = null
     ): FirProperty {
+        checkStatusIsResolved(baseProperty)
+
         return buildProperty {
             source = baseProperty.source
             moduleData = session.moduleData
@@ -724,4 +730,12 @@ object FirFakeOverrideGenerator {
         class Value<out A>(val value: A) : Maybe<A>()
         object Nothing : Maybe<kotlin.Nothing>()
     }
+
+    private fun checkStatusIsResolved(member: FirCallableDeclaration) {
+        check(member.status is FirResolvedDeclarationStatus) {
+            "Status should be resolved for a declaration to create it fake override, " +
+                    "otherwise the status of the fake override will never be resolved." +
+                    "The status was unresolved for ${member::class.java.simpleName}"
+        }
+    }
 }