FIR: Clarify contracts for two versions FirClass<*>::scope

- One of them really creates a scope a specific type
- Another one is used for supertypes and includes creation of FirDelegatedMemberScope wrapper

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/ScopeUtils.kt

@@ -15,7 +15,7 @@ import org.jetbrains.kotlin.fir.resolve.transformers.ensureResolved
 import org.jetbrains.kotlin.fir.scopes.FirTypeScope
 import org.jetbrains.kotlin.fir.scopes.impl.FirStandardOverrideChecker
 import org.jetbrains.kotlin.fir.scopes.impl.FirTypeIntersectionScope
-import org.jetbrains.kotlin.fir.scopes.scope
+import org.jetbrains.kotlin.fir.scopes.scopeForClass
 import org.jetbrains.kotlin.fir.symbols.impl.FirTypeParameterSymbol
 import org.jetbrains.kotlin.fir.typeContext
 import org.jetbrains.kotlin.fir.types.*
@@ -39,7 +39,7 @@ private fun ConeKotlinType.scope(useSiteSession: FirSession, scopeSession: Scope
 
             val substitution = createSubstitution(fir.typeParameters, fullyExpandedType, useSiteSession)
 
-            fir.scope(substitutorByMap(substitution), useSiteSession, scopeSession, skipPrivateMembers = false)
+            fir.scopeForClass(substitutorByMap(substitution), useSiteSession, scopeSession)
         }
         is ConeTypeParameterType -> {
             val symbol = lookupTag.toSymbol()

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/calls/ConstructorProcessing.kt

@@ -16,7 +16,7 @@ import org.jetbrains.kotlin.fir.resolve.substitution.substitutorByMap
 import org.jetbrains.kotlin.fir.resolve.transformers.ensureResolved
 import org.jetbrains.kotlin.fir.scopes.FirScope
 import org.jetbrains.kotlin.fir.scopes.impl.FirClassSubstitutionScope
-import org.jetbrains.kotlin.fir.scopes.scope
+import org.jetbrains.kotlin.fir.scopes.scopeForClass
 import org.jetbrains.kotlin.fir.symbols.impl.*
 import org.jetbrains.kotlin.fir.types.*
 import org.jetbrains.kotlin.name.Name
@@ -153,8 +153,8 @@ private fun processConstructors(
                     } else basicScope
                 }
                 is FirClassSymbol ->
-                    (matchedSymbol.fir as FirClass<*>).scope(
-                        substitutor, session, scopeSession, skipPrivateMembers = false,
+                    (matchedSymbol.fir as FirClass<*>).scopeForClass(
+                        substitutor, session, scopeSession
                     )
             }
 

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/scopes/KotlinScopeProvider.kt

@@ -13,6 +13,7 @@ import org.jetbrains.kotlin.fir.resolve.substitution.ConeSubstitutor
 import org.jetbrains.kotlin.fir.resolve.substitution.substitutorByMap
 import org.jetbrains.kotlin.fir.scopes.impl.*
 import org.jetbrains.kotlin.fir.symbols.CallableId
+import org.jetbrains.kotlin.fir.symbols.ConeClassLikeLookupTag
 import org.jetbrains.kotlin.fir.symbols.impl.FirRegularClassSymbol
 import org.jetbrains.kotlin.fir.types.ConeClassErrorType
 import org.jetbrains.kotlin.fir.types.ConeClassLikeType
@@ -44,12 +45,10 @@ class KotlinScopeProvider(
                     val symbol = useSiteSuperType.lookupTag.toSymbol(useSiteSession)
                     if (symbol is FirRegularClassSymbol) {
                         val delegateField = delegateFields.find { it.returnTypeRef.coneType == useSiteSuperType }
-                        symbol.fir.scope(
+                        symbol.fir.scopeForSupertype(
                             substitutor(symbol, useSiteSuperType, useSiteSession),
                             useSiteSession, scopeSession, delegateField,
-                            skipPrivateMembers = true,
-                            classId = klass.classId,
-                            isFromExpectClass = (klass as? FirRegularClass)?.isExpect == true
+                            subClass = klass
                         ).let {
                             it as? FirTypeScope ?: error("$it is expected to be FirOverrideAwareScope")
                         }
@@ -101,32 +100,58 @@ fun FirClass<*>.unsubstitutedScope(useSiteSession: FirSession, scopeSession: Sco
     return scopeProvider.getUseSiteMemberScope(this, useSiteSession, scopeSession)
 }
 
-internal fun FirClass<*>.scope(
+fun FirClass<*>.scopeForClass(
+    substitutor: ConeSubstitutor,
+    useSiteSession: FirSession,
+    scopeSession: ScopeSession
+): FirTypeScope = scopeForClassImpl(
+    substitutor, useSiteSession, scopeSession,
+    skipPrivateMembers = false,
+    containingClassForAdditionalMembers = symbol.toLookupTag(),
+    // TODO: why it's always false?
+    isFromExpectClass = false
+)
+
+private fun FirClass<*>.scopeForSupertype(
     substitutor: ConeSubstitutor,
     useSiteSession: FirSession,
     scopeSession: ScopeSession,
-    delegateField: FirField? = null,
-    skipPrivateMembers: Boolean,
-    classId: ClassId? = this.classId,
-    isFromExpectClass: Boolean = false
-): FirTypeScope {
-    val basicScope = unsubstitutedScope(useSiteSession, scopeSession).let {
-        if (delegateField != null) {
-            scopeSession.getOrBuild(delegateField, DelegatedMemberScopeKey(delegateField.symbol.callableId)) {
-                FirDelegatedMemberScope(it, useSiteSession)
-            }
-        } else {
-            it
+    delegateField: FirField?,
+    subClass: FirClass<*>
+): FirTypeScope = scopeForClassImpl(
+    substitutor,
+    useSiteSession,
+    scopeSession,
+    skipPrivateMembers = true,
+    containingClassForAdditionalMembers = subClass.symbol.toLookupTag(),
+    isFromExpectClass = (subClass as? FirRegularClass)?.isExpect == true
+).let {
+    if (delegateField != null) {
+        scopeSession.getOrBuild(delegateField, DelegatedMemberScopeKey(delegateField.symbol.callableId)) {
+            FirDelegatedMemberScope(it, useSiteSession, subClass.symbol.toLookupTag(), delegateField)
         }
+    } else {
+        it
     }
+}
+
+private fun FirClass<*>.scopeForClassImpl(
+    substitutor: ConeSubstitutor,
+    useSiteSession: FirSession,
+    scopeSession: ScopeSession,
+    skipPrivateMembers: Boolean,
+    containingClassForAdditionalMembers: ConeClassLikeLookupTag,
+    isFromExpectClass: Boolean
+): FirTypeScope {
+    val basicScope = unsubstitutedScope(useSiteSession, scopeSession)
     if (substitutor == ConeSubstitutor.Empty) return basicScope
 
     return scopeSession.getOrBuild(
-        this, ConeSubstitutionScopeKey(classId, isFromExpectClass, substitutor)
+        this, ConeSubstitutionScopeKey(containingClassForAdditionalMembers.classId, isFromExpectClass, substitutor)
     ) {
         FirClassSubstitutionScope(
             useSiteSession, basicScope, scopeSession, substitutor,
-            skipPrivateMembers, classId, makeExpect = isFromExpectClass
+            skipPrivateMembers, containingClassForAdditionalMembers.classId, makeExpect = isFromExpectClass
         )
     }
 }