CandidateApplicability: add K1/K2 prefixes when applicable

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

@@ -408,7 +408,7 @@ class FirCallResolver(
             noSuccessfulCandidates -> {
                 val errorReference = buildErrorReference(
                     info,
-                    if (applicability == CandidateApplicability.UNSUPPORTED) {
+                    if (applicability == CandidateApplicability.K2_UNSUPPORTED) {
                         val unsupportedResolutionDiagnostic = reducedCandidates.firstOrNull()?.diagnostics?.firstOrNull() as? Unsupported
                         ConeUnsupported(unsupportedResolutionDiagnostic?.message ?: "", unsupportedResolutionDiagnostic?.source)
                     } else {

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

@@ -571,9 +571,9 @@ fun createConeDiagnosticForCandidateWithError(
 ): ConeDiagnostic {
     return when (applicability) {
         CandidateApplicability.HIDDEN -> ConeHiddenCandidateError(candidate)
-        CandidateApplicability.VISIBILITY_ERROR -> ConeVisibilityError(candidate.symbol)
+        CandidateApplicability.K2_VISIBILITY_ERROR -> ConeVisibilityError(candidate.symbol)
         CandidateApplicability.INAPPLICABLE_WRONG_RECEIVER -> ConeInapplicableWrongReceiver(listOf(candidate))
-        CandidateApplicability.NO_COMPANION_OBJECT -> ConeNoCompanionObject(candidate)
+        CandidateApplicability.K2_NO_COMPANION_OBJECT -> ConeNoCompanionObject(candidate)
         else -> ConeInapplicableCandidateError(applicability, candidate)
     }
 }

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

@@ -8,7 +8,7 @@ package org.jetbrains.kotlin.fir.resolve.calls
 import org.jetbrains.kotlin.fir.resolve.BodyResolveComponents
 import org.jetbrains.kotlin.fir.resolve.calls.tower.TowerGroup
 import org.jetbrains.kotlin.resolve.calls.tower.CandidateApplicability
-import org.jetbrains.kotlin.resolve.calls.tower.CandidateApplicability.DSL_SCOPE_VIOLATION
+import org.jetbrains.kotlin.resolve.calls.tower.CandidateApplicability.K2_DSL_SCOPE_VIOLATION
 import org.jetbrains.kotlin.resolve.calls.tower.CandidateApplicability.K2_SYNTHETIC_RESOLVED
 import org.jetbrains.kotlin.resolve.calls.tower.isSuccess
 
@@ -53,7 +53,7 @@ open class CandidateCollector(
         shouldStopResolve && bestGroup < group
 
     private val shouldStopResolve: Boolean
-        get() = currentApplicability == DSL_SCOPE_VIOLATION || currentApplicability >= K2_SYNTHETIC_RESOLVED
+        get() = currentApplicability == K2_DSL_SCOPE_VIOLATION || currentApplicability >= K2_SYNTHETIC_RESOLVED
 
     val isSuccess: Boolean
         get() = currentApplicability.isSuccess

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/providers/impl/FirTypeResolverImpl.kt

@@ -123,7 +123,7 @@ class FirTypeResolverImpl(private val session: FirSession) : FirTypeResolver() {
             var diagnostic: ConeDiagnostic? = null
 
             if (!symbol.isVisible(useSiteFile, containingDeclarations, supertypeSupplier)) {
-                symbolApplicability = minOf(CandidateApplicability.VISIBILITY_ERROR, symbolApplicability)
+                symbolApplicability = minOf(CandidateApplicability.K2_VISIBILITY_ERROR, symbolApplicability)
                 diagnostic = ConeVisibilityError(symbol)
             }
 

compiler/fir/semantics/src/org/jetbrains/kotlin/fir/resolve/calls/ResolutionDiagnostic.kt

@@ -80,7 +80,7 @@ object InapplicableCandidate : ResolutionDiagnostic(INAPPLICABLE)
 
 object HiddenCandidate : ResolutionDiagnostic(HIDDEN)
 
-object VisibilityError : ResolutionDiagnostic(VISIBILITY_ERROR)
+object VisibilityError : ResolutionDiagnostic(K2_VISIBILITY_ERROR)
 
 object ResolvedWithLowPriority : ResolutionDiagnostic(RESOLVED_LOW_PRIORITY)
 
@@ -91,7 +91,7 @@ class InapplicableWrongReceiver(
     val actualType: ConeKotlinType? = null,
 ) : ResolutionDiagnostic(INAPPLICABLE_WRONG_RECEIVER)
 
-object NoCompanionObject : ResolutionDiagnostic(NO_COMPANION_OBJECT)
+object NoCompanionObject : ResolutionDiagnostic(K2_NO_COMPANION_OBJECT)
 
 class UnsafeCall(val actualType: ConeKotlinType) : ResolutionDiagnostic(UNSAFE_CALL)
 
@@ -123,11 +123,11 @@ class InfixCallOfNonInfixFunction(val function: FirNamedFunctionSymbol) : Resolu
 class OperatorCallOfNonOperatorFunction(val function: FirNamedFunctionSymbol) : ResolutionDiagnostic(CONVENTION_ERROR)
 
 class InferenceError(val constraintError: ConstraintSystemError) : ResolutionDiagnostic(constraintError.applicability)
-class Unsupported(val message: String, val source: KtSourceElement? = null) : ResolutionDiagnostic(UNSUPPORTED)
+class Unsupported(val message: String, val source: KtSourceElement? = null) : ResolutionDiagnostic(K2_UNSUPPORTED)
 
 object PropertyAsOperator : ResolutionDiagnostic(K2_PROPERTY_AS_OPERATOR)
 
-class DslScopeViolation(val calleeSymbol: FirBasedSymbol<*>) : ResolutionDiagnostic(DSL_SCOPE_VIOLATION)
+class DslScopeViolation(val calleeSymbol: FirBasedSymbol<*>) : ResolutionDiagnostic(K2_DSL_SCOPE_VIOLATION)
 
 class MultipleContextReceiversApplicableForExtensionReceivers : ResolutionDiagnostic(INAPPLICABLE)
 

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/util/resolvedCallUtil.kt

@@ -124,7 +124,7 @@ fun ResolvedCall<*>.hasInferredReturnType(): Boolean {
 fun CandidateApplicability.toResolutionStatus(): ResolutionStatus = when (this) {
     CandidateApplicability.RESOLVED,
     CandidateApplicability.RESOLVED_LOW_PRIORITY,
-    CandidateApplicability.RESOLVED_WITH_ERROR,
+    CandidateApplicability.K1_RESOLVED_WITH_ERROR,
     CandidateApplicability.RESOLVED_NEED_PRESERVE_COMPATIBILITY -> ResolutionStatus.SUCCESS
     CandidateApplicability.INAPPLICABLE_WRONG_RECEIVER -> ResolutionStatus.RECEIVER_TYPE_ERROR
     CandidateApplicability.UNSAFE_CALL -> ResolutionStatus.UNSAFE_CALL_ERROR

compiler/resolution.common/src/org/jetbrains/kotlin/resolve/calls/tower/CandidateApplicability.kt

@@ -6,29 +6,31 @@
 package org.jetbrains.kotlin.resolve.calls.tower
 
 enum class CandidateApplicability {
-    RESOLVED_TO_SAM_WITH_VARARG, // migration warning up to 1.5 (when resolve to function with SAM conversion and array without spread as vararg)
+    K1_RESOLVED_TO_SAM_WITH_VARARG, // migration warning up to 1.5 (when resolve to function with SAM conversion and array without spread as vararg)
-    HIDDEN, // removed from resolve
+    HIDDEN, // removed from resolve (should get UNRESOLVED_REFERENCE, used for HIDDEN deprecations and similar things)
-    VISIBILITY_ERROR, // problems with visibility
+    K2_VISIBILITY_ERROR, // problems with visibility (should get INVISIBLE_REFERENCE)
-    UNSUPPORTED, // unsupported feature
+    K2_UNSUPPORTED, // unsupported feature
     INAPPLICABLE_WRONG_RECEIVER, // receiver not matched
     INAPPLICABLE_ARGUMENTS_MAPPING_ERROR, // arguments not mapped to parameters (i.e. different size of arguments and parameters)
     INAPPLICABLE, // arguments have wrong types
-    NO_COMPANION_OBJECT, // Classifier does not have a companion object
+    K2_NO_COMPANION_OBJECT, // Classifier does not have a companion object
-    IMPOSSIBLE_TO_GENERATE, // access to outer class from nested
+    K1_IMPOSSIBLE_TO_GENERATE, // access to outer class from nested
-    RUNTIME_ERROR, // TODO: FE 1.0 uses this as catch-all for all other errors. Consider re-assigning those diagnostics.
+    K1_RUNTIME_ERROR, // TODO: FE 1.0 uses this as catch-all for all other errors. Consider re-assigning those diagnostics.
     UNSAFE_CALL, // receiver or argument nullability doesn't match
     UNSTABLE_SMARTCAST, // unstable smart cast
     CONVENTION_ERROR, // missing infix, operator etc (= no expected modifier)
 
-    // Below has shouldStopResolve = true
+    K2_DSL_SCOPE_VIOLATION, // Skip other levels for DSL_SCOPE_VIOLATION because if the candidate is marked DSL_SCOPE_VIOLATION with an inner receiver, one should not keep going to outer receivers.
-    DSL_SCOPE_VIOLATION, // Skip other levels for DSL_SCOPE_VIOLATION because if the candidate is marked DSL_SCOPE_VIOLATION with an inner receiver, one should not keep going to outer receivers.
 
     // Below has isSuccess = true
     RESOLVED_LOW_PRIORITY,
     K2_PROPERTY_AS_OPERATOR, // using property of functional type as an operator. From resolution perspective, this is considered successful.
     RESOLVED_NEED_PRESERVE_COMPATIBILITY, // call resolved successfully, but using new features that changes resolve
+
+    // Tower resolve does not go to further scopes if candidate with applicability below is found
+
     K2_SYNTHETIC_RESOLVED, // used in K2 for (Java) synthetic discrimination at the same level
-    RESOLVED_WITH_ERROR, // call has error, but it is still successful from resolution perspective
+    K1_RESOLVED_WITH_ERROR, // call has error, but it is still successful from resolution perspective
     RESOLVED, // call success or has uncompleted inference or in other words possible successful candidate
 }
 

compiler/resolution/src/org/jetbrains/kotlin/resolve/calls/model/KotlinCallDiagnostics.kt

@@ -157,7 +157,7 @@ class NotCallableExpectedType(
 ) : CallableReferenceInapplicableDiagnostic(argument)
 
 class AdaptedCallableReferenceIsUsedWithReflection(val argument: CallableReferenceResolutionAtom) :
-    CallableReferenceInapplicableDiagnostic(argument, RESOLVED_WITH_ERROR)
+    CallableReferenceInapplicableDiagnostic(argument, K1_RESOLVED_WITH_ERROR)
 
 // SmartCasts
 class SmartCastDiagnostic(
@@ -194,7 +194,7 @@ class UnstableSmartCastResolutionError(
 class UnstableSmartCastDiagnosticError(
     argument: ExpressionKotlinCallArgument,
     targetType: UnwrappedType,
-) : UnstableSmartCast(argument, targetType, RESOLVED_WITH_ERROR)
+) : UnstableSmartCast(argument, targetType, K1_RESOLVED_WITH_ERROR)
 
 class UnsafeCallError(
     val receiver: SimpleKotlinCallArgument,
@@ -204,23 +204,23 @@ class UnsafeCallError(
 }
 
 // Other
-object InstantiationOfAbstractClass : KotlinCallDiagnostic(RUNTIME_ERROR) {
+object InstantiationOfAbstractClass : KotlinCallDiagnostic(K1_RUNTIME_ERROR) {
     override fun report(reporter: DiagnosticReporter) = reporter.onCall(this)
 }
 
-class AbstractSuperCall(val receiver: SimpleKotlinCallArgument) : KotlinCallDiagnostic(RUNTIME_ERROR) {
+class AbstractSuperCall(val receiver: SimpleKotlinCallArgument) : KotlinCallDiagnostic(K1_RUNTIME_ERROR) {
     override fun report(reporter: DiagnosticReporter) {
         reporter.onCall(this)
     }
 }
 
-object AbstractFakeOverrideSuperCall : KotlinCallDiagnostic(RUNTIME_ERROR) {
+object AbstractFakeOverrideSuperCall : KotlinCallDiagnostic(K1_RUNTIME_ERROR) {
     override fun report(reporter: DiagnosticReporter) {
         reporter.onCall(this)
     }
 }
 
-class SuperAsExtensionReceiver(val receiver: SimpleKotlinCallArgument) : KotlinCallDiagnostic(RUNTIME_ERROR) {
+class SuperAsExtensionReceiver(val receiver: SimpleKotlinCallArgument) : KotlinCallDiagnostic(K1_RUNTIME_ERROR) {
     override fun report(reporter: DiagnosticReporter) {
         reporter.onCallReceiver(receiver, this)
     }
@@ -273,7 +273,7 @@ class ArgumentNullabilityWarningDiagnostic(
     }
 }
 
-class ResolvedToSamWithVarargDiagnostic(val argument: KotlinCallArgument) : KotlinCallDiagnostic(RESOLVED_TO_SAM_WITH_VARARG) {
+class ResolvedToSamWithVarargDiagnostic(val argument: KotlinCallArgument) : KotlinCallDiagnostic(K1_RESOLVED_TO_SAM_WITH_VARARG) {
     override fun report(reporter: DiagnosticReporter) {
         reporter.onCallArgument(argument, this)
     }
@@ -282,7 +282,7 @@ class ResolvedToSamWithVarargDiagnostic(val argument: KotlinCallArgument) : Kotl
 class NotEnoughInformationForLambdaParameter(
     val lambdaArgument: LambdaKotlinCallArgument,
     val parameterIndex: Int
-) : KotlinCallDiagnostic(RESOLVED_WITH_ERROR) {
+) : KotlinCallDiagnostic(K1_RESOLVED_WITH_ERROR) {
     override fun report(reporter: DiagnosticReporter) {
         reporter.onCallArgument(lambdaArgument, this)
     }

compiler/resolution/src/org/jetbrains/kotlin/resolve/calls/tower/ImplicitScopeTower.kt

@@ -114,20 +114,20 @@ abstract class ResolutionDiagnostic(candidateApplicability: CandidateApplicabili
     }
 }
 
-class ContextReceiverAmbiguity : ResolutionDiagnostic(RESOLVED_WITH_ERROR) {
+class ContextReceiverAmbiguity : ResolutionDiagnostic(K1_RESOLVED_WITH_ERROR) {
     override fun report(reporter: DiagnosticReporter) {
         reporter.onCall(this)
     }
 }
 
-class UnsupportedContextualDeclarationCall : ResolutionDiagnostic(RESOLVED_WITH_ERROR) {
+class UnsupportedContextualDeclarationCall : ResolutionDiagnostic(K1_RESOLVED_WITH_ERROR) {
     override fun report(reporter: DiagnosticReporter) {
         reporter.onCall(this)
     }
 }
 
 // todo error for this access from nested class
-class VisibilityError(val invisibleMember: DeclarationDescriptorWithVisibility) : ResolutionDiagnostic(RUNTIME_ERROR) {
+class VisibilityError(val invisibleMember: DeclarationDescriptorWithVisibility) : ResolutionDiagnostic(K1_RUNTIME_ERROR) {
     override fun report(reporter: DiagnosticReporter) {
         reporter.onCall(this)
     }
@@ -136,15 +136,15 @@ class VisibilityError(val invisibleMember: DeclarationDescriptorWithVisibility)
 class VisibilityErrorOnArgument(
     val argument: KotlinCallArgument,
     val invisibleMember: DeclarationDescriptorWithVisibility
-) : ResolutionDiagnostic(RUNTIME_ERROR) {
+) : ResolutionDiagnostic(K1_RUNTIME_ERROR) {
     override fun report(reporter: DiagnosticReporter) {
         reporter.onCallArgument(argument, this)
     }
 }
 
-class NestedClassViaInstanceReference(val classDescriptor: ClassDescriptor) : ResolutionDiagnostic(IMPOSSIBLE_TO_GENERATE)
+class NestedClassViaInstanceReference(val classDescriptor: ClassDescriptor) : ResolutionDiagnostic(K1_IMPOSSIBLE_TO_GENERATE)
-class InnerClassViaStaticReference(val classDescriptor: ClassDescriptor) : ResolutionDiagnostic(IMPOSSIBLE_TO_GENERATE)
+class InnerClassViaStaticReference(val classDescriptor: ClassDescriptor) : ResolutionDiagnostic(K1_IMPOSSIBLE_TO_GENERATE)
-class UnsupportedInnerClassCall(val message: String) : ResolutionDiagnostic(IMPOSSIBLE_TO_GENERATE)
+class UnsupportedInnerClassCall(val message: String) : ResolutionDiagnostic(K1_IMPOSSIBLE_TO_GENERATE)
 class UsedSmartCastForDispatchReceiver(val smartCastType: KotlinType) : ResolutionDiagnostic(RESOLVED)
 
 object ErrorDescriptorDiagnostic : ResolutionDiagnostic(RESOLVED) // todo discuss and change to INAPPLICABLE

compiler/resolution/src/org/jetbrains/kotlin/resolve/calls/tower/TowerResolver.kt

@@ -457,7 +457,7 @@ class TowerResolver {
 
         private fun isSuccessfulCandidate(candidate: C): Boolean {
             return candidate.resultingApplicability == CandidateApplicability.RESOLVED
-                    || candidate.resultingApplicability == CandidateApplicability.RESOLVED_WITH_ERROR
+                    || candidate.resultingApplicability == CandidateApplicability.K1_RESOLVED_WITH_ERROR
         }
 
         private fun isSuccessfulPreserveCompatibility(candidate: C): Boolean =