Refactoring. Support in OverloadingConflictResolver any kind of ResolvedCalls.

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/results/FlatSignature.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2015 JetBrains s.r.o.
+ * Copyright 2010-2016 JetBrains s.r.o.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -19,12 +19,8 @@ package org.jetbrains.kotlin.resolve.calls.results
 import org.jetbrains.kotlin.descriptors.CallableDescriptor
 import org.jetbrains.kotlin.descriptors.TypeParameterDescriptor
 import org.jetbrains.kotlin.descriptors.ValueParameterDescriptor
-import org.jetbrains.kotlin.psi.ValueArgument
-import org.jetbrains.kotlin.resolve.calls.model.DefaultValueArgument
-import org.jetbrains.kotlin.resolve.calls.model.ResolvedCall
 import org.jetbrains.kotlin.types.KotlinType
 import org.jetbrains.kotlin.utils.singletonOrEmptyList
-import java.util.*
 
 class FlatSignature<out T>(
         val origin: T,
@@ -37,34 +33,6 @@ class FlatSignature<out T>(
     val isGeneric = typeParameters.isNotEmpty()
 
     companion object {
-        fun <D : CallableDescriptor, RC : ResolvedCall<D>> createFromResolvedCall(resolvedCall: RC): FlatSignature<RC> {
-            val originalDescriptor = resolvedCall.candidateDescriptor.original
-            val originalValueParameters = originalDescriptor.valueParameters
-
-            var numDefaults = 0
-            val valueArgumentToParameterType = HashMap<ValueArgument, KotlinType>()
-            for ((valueParameter, resolvedValueArgument) in resolvedCall.valueArguments.entries) {
-                if (resolvedValueArgument is DefaultValueArgument) {
-                    numDefaults++
-                }
-                else {
-                    val originalValueParameter = originalValueParameters[valueParameter.index]
-                    val parameterType = originalValueParameter.argumentValueType
-                    for (valueArgument in resolvedValueArgument.arguments) {
-                        valueArgumentToParameterType[valueArgument] = parameterType
-                    }
-                }
-            }
-
-            return FlatSignature(resolvedCall,
-                                 originalDescriptor.typeParameters,
-                                 valueParameterTypes = originalDescriptor.extensionReceiverTypeOrEmpty() +
-                                                       resolvedCall.call.valueArguments.map { valueArgumentToParameterType[it] },
-                                 hasExtensionReceiver = originalDescriptor.extensionReceiverParameter != null,
-                                 hasVarargs = originalDescriptor.valueParameters.any { it.varargElementType != null },
-                                 numDefaults = numDefaults)
-        }
-
         fun <D : CallableDescriptor> createFromCallableDescriptor(descriptor: D): FlatSignature<D> =
                 FlatSignature(descriptor,
                               descriptor.typeParameters,

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/results/FlatSignatureSpecificity.kt

@@ -16,14 +16,24 @@
 
 package org.jetbrains.kotlin.resolve.calls.results
 
+import org.jetbrains.kotlin.builtins.KotlinBuiltIns
+import org.jetbrains.kotlin.psi.ValueArgument
+import org.jetbrains.kotlin.resolve.DescriptorToSourceUtils
 import org.jetbrains.kotlin.resolve.calls.inference.CallHandle
 import org.jetbrains.kotlin.resolve.calls.inference.ConstraintSystem
 import org.jetbrains.kotlin.resolve.calls.inference.ConstraintSystemBuilderImpl
 import org.jetbrains.kotlin.resolve.calls.inference.constraintPosition.valueParameterPosition
+import org.jetbrains.kotlin.resolve.calls.model.DefaultValueArgument
+import org.jetbrains.kotlin.resolve.calls.model.MutableResolvedCall
+import org.jetbrains.kotlin.resolve.calls.model.ResolvedCall
+import org.jetbrains.kotlin.resolve.calls.model.VariableAsFunctionResolvedCallImpl
+import org.jetbrains.kotlin.resolve.calls.results.FlatSignature.Companion.argumentValueType
+import org.jetbrains.kotlin.resolve.calls.results.FlatSignature.Companion.extensionReceiverTypeOrEmpty
 import org.jetbrains.kotlin.types.KotlinType
 import org.jetbrains.kotlin.types.TypeUtils
 import org.jetbrains.kotlin.types.Variance
 import org.jetbrains.kotlin.types.checker.KotlinTypeChecker
+import java.util.*
 
 interface SpecificityComparisonCallbacks {
     fun isNonSubtypeNotLessSpecific(specific: KotlinType, general: KotlinType): Boolean
@@ -76,3 +86,44 @@ fun <T> isSignatureNotLessSpecific(
     val constraintSystem = constraintSystemBuilder.build()
     return !constraintSystem.status.hasContradiction()
 }
+
+
+fun <RC : ResolvedCall<*>> RC.createFlatSignature(): FlatSignature<RC> {
+    val originalDescriptor = candidateDescriptor.original
+    val originalValueParameters = originalDescriptor.valueParameters
+
+    var numDefaults = 0
+    val valueArgumentToParameterType = HashMap<ValueArgument, KotlinType>()
+    for ((valueParameter, resolvedValueArgument) in valueArguments.entries) {
+        if (resolvedValueArgument is DefaultValueArgument) {
+            numDefaults++
+        }
+        else {
+            val originalValueParameter = originalValueParameters[valueParameter.index]
+            val parameterType = originalValueParameter.argumentValueType
+            for (valueArgument in resolvedValueArgument.arguments) {
+                valueArgumentToParameterType[valueArgument] = parameterType
+            }
+        }
+    }
+
+    return FlatSignature(this,
+                         originalDescriptor.typeParameters,
+                         valueParameterTypes = originalDescriptor.extensionReceiverTypeOrEmpty() +
+                                               call.valueArguments.map { valueArgumentToParameterType[it] },
+                         hasExtensionReceiver = originalDescriptor.extensionReceiverParameter != null,
+                         hasVarargs = originalDescriptor.valueParameters.any { it.varargElementType != null },
+                         numDefaults = numDefaults)
+}
+
+fun createOverloadingConflictResolver(
+        builtIns: KotlinBuiltIns,
+        specificityComparator: TypeSpecificityComparator
+) = OverloadingConflictResolver(
+        builtIns,
+        specificityComparator,
+        MutableResolvedCall<*>::getResultingDescriptor,
+        MutableResolvedCall<*>::createFlatSignature,
+        { (it as? VariableAsFunctionResolvedCallImpl)?.variableCall },
+        { DescriptorToSourceUtils.descriptorToDeclaration(it) != null}
+)

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/results/OverloadingConflictResolver.kt

@@ -21,28 +21,105 @@ import gnu.trove.TObjectHashingStrategy
 import org.jetbrains.kotlin.builtins.KotlinBuiltIns
 import org.jetbrains.kotlin.descriptors.CallableDescriptor
 import org.jetbrains.kotlin.descriptors.ScriptDescriptor
-import org.jetbrains.kotlin.descriptors.VariableDescriptor
 import org.jetbrains.kotlin.descriptors.Visibilities
+import org.jetbrains.kotlin.resolve.DescriptorEquivalenceForOverrides
+import org.jetbrains.kotlin.resolve.OverridingUtil
 import org.jetbrains.kotlin.resolve.calls.context.CheckArgumentTypesMode
-import org.jetbrains.kotlin.resolve.calls.model.MutableResolvedCall
-import org.jetbrains.kotlin.resolve.calls.model.ResolvedCall
-import org.jetbrains.kotlin.resolve.calls.model.VariableAsFunctionMutableResolvedCall
-import org.jetbrains.kotlin.resolve.calls.model.VariableAsFunctionResolvedCall
 import org.jetbrains.kotlin.resolve.descriptorUtil.varargParameterPosition
 import org.jetbrains.kotlin.types.KotlinType
 import org.jetbrains.kotlin.types.TypeUtils
+import java.util.*
 
-class OverloadingConflictResolver(
+class OverloadingConflictResolver<C : Any>(
         private val builtIns: KotlinBuiltIns,
-        private val specificityComparator: TypeSpecificityComparator
+        private val specificityComparator: TypeSpecificityComparator,
+        private val getResultingDescriptor: (C) -> CallableDescriptor,
+        private val createFlatSignature: (C) -> FlatSignature<C>,
+        private val getVariableCandidates: (C) -> C?, // vor variable WithInvoke
+        private val isFromSources: (CallableDescriptor) -> Boolean
 ) {
 
-    fun <D : CallableDescriptor> findMaximallySpecific(
+    private val resolvedCallHashingStrategy = object : TObjectHashingStrategy<C> {
-            candidates: Set<MutableResolvedCall<D>>,
+        override fun equals(call1: C?, call2: C?): Boolean =
+                if (call1 != null && call2 != null)
+                    call1.resultingDescriptor == call2.resultingDescriptor
+                else
+                    call1 == call2
+
+        override fun computeHashCode(call: C?): Int =
+                call?.resultingDescriptor?.hashCode() ?: 0
+    }
+
+    private val C.resultingDescriptor: CallableDescriptor get() = getResultingDescriptor(this)
+
+    // if result contains only one element -- it is maximally specific; otherwise we have ambiguity
+    fun chooseMaximallySpecificCandidates(
+            candidates: Set<C>,
             checkArgumentsMode: CheckArgumentTypesMode,
             discriminateGenerics: Boolean,
             isDebuggerContext: Boolean
-    ): MutableResolvedCall<D>? =
+    ): Set<C> {
+        if (candidates.size == 1) return candidates
+
+        val fixedCandidates = if (getVariableCandidates(candidates.first()) != null) {
+            findMaximallySpecificVariableAsFunctionCalls(candidates) ?: return candidates
+        }
+        else {
+            candidates
+        }
+
+        val noEquivalentCalls = filterOutEquivalentCalls(fixedCandidates)
+        val noOverrides = OverridingUtil.filterOverrides(noEquivalentCalls) { it.resultingDescriptor }
+        if (noOverrides.size == 1) {
+            return noOverrides
+        }
+
+        val maximallySpecific = findMaximallySpecific(noOverrides, checkArgumentsMode, false, isDebuggerContext)
+        if (maximallySpecific != null) {
+            return setOf(maximallySpecific)
+        }
+
+        if (discriminateGenerics) {
+            val maximallySpecificGenericsDiscriminated = findMaximallySpecific(noOverrides, checkArgumentsMode, true, isDebuggerContext)
+            if (maximallySpecificGenericsDiscriminated != null) {
+                return setOf(maximallySpecificGenericsDiscriminated)
+            }
+        }
+
+        return noOverrides
+    }
+
+    // Sometimes we should compare "copies" from sources and from binary files.
+    // But we cannot compare return types for such copies, because it may lead us to recursive problem (see KT-11995).
+    // Because of this we compare them without return type and choose descriptor from source if we found duplicate.
+    private fun filterOutEquivalentCalls(
+            candidates: Set<C>): Set<C> {
+        if (candidates.size <= 1) return candidates
+
+        val fromSourcesGoesFirst = candidates.sortedBy { if (isFromSources(it.resultingDescriptor)) 0 else 1 }
+
+        val result = LinkedHashSet<C>()
+        outerLoop@ for (meD in fromSourcesGoesFirst) {
+            for (otherD in result) {
+                val me = meD.resultingDescriptor
+                val other = otherD.resultingDescriptor
+                val ignoreReturnType = isFromSources(me) != isFromSources(other)
+                if (DescriptorEquivalenceForOverrides.areCallableDescriptorsEquivalent(me, other, ignoreReturnType)) {
+                    continue@outerLoop
+                }
+            }
+            result.add(meD)
+        }
+
+        return result
+    }
+
+    private fun findMaximallySpecific(
+            candidates: Set<C>,
+            checkArgumentsMode: CheckArgumentTypesMode,
+            discriminateGenerics: Boolean,
+            isDebuggerContext: Boolean
+    ): C? =
             if (candidates.size <= 1)
                 candidates.firstOrNull()
             else when (checkArgumentsMode) {
@@ -58,33 +135,31 @@ class OverloadingConflictResolver(
                     findMaximallySpecificCall(candidates, discriminateGenerics, isDebuggerContext)
             }
 
-    fun <D : CallableDescriptor> findMaximallySpecificVariableAsFunctionCalls(candidates: Set<MutableResolvedCall<D>>): Set<MutableResolvedCall<D>> {
+    // null means ambiguity between variables
-        val variableCalls = candidates.mapTo(newResolvedCallSet<MutableResolvedCall<VariableDescriptor>>(candidates.size)) {
+    private fun findMaximallySpecificVariableAsFunctionCalls(candidates: Set<C>): Set<C>? {
-            if (it is VariableAsFunctionMutableResolvedCall)
+        val variableCalls = candidates.mapTo(newResolvedCallSet(candidates.size)) {
-                it.variableCall
+            getVariableCandidates(it) ?: throw AssertionError("Regular call among variable-as-function calls: $it")
-            else
-                throw AssertionError("Regular call among variable-as-function calls: $it")
         }
 
-        val maxSpecificVariableCall = findMaximallySpecificCall(variableCalls, false, false) ?: return emptySet()
+        val maxSpecificVariableCall = findMaximallySpecificCall(variableCalls, false, false) ?: return null
 
-        return candidates.filterTo(newResolvedCallSet<MutableResolvedCall<D>>(2)) {
+        return candidates.filterTo(newResolvedCallSet(2)) {
-            it.resultingVariableDescriptor == maxSpecificVariableCall.resultingDescriptor
+            getVariableCandidates(it)!!.resultingDescriptor == maxSpecificVariableCall.resultingDescriptor
         }
     }
 
-    private fun <D : CallableDescriptor> findMaximallySpecificCall(
+    private fun findMaximallySpecificCall(
-            candidates: Set<MutableResolvedCall<D>>,
+            candidates: Set<C>,
             discriminateGenerics: Boolean,
             isDebuggerContext: Boolean
-    ): MutableResolvedCall<D>? {
+    ): C? {
         val filteredCandidates = uniquifyCandidatesSet(candidates)
 
         if (filteredCandidates.size <= 1) return filteredCandidates.singleOrNull()
 
         val conflictingCandidates = filteredCandidates.map {
             candidateCall ->
-            FlatSignature.createFromResolvedCall(candidateCall)
+            createFlatSignature(candidateCall)
         }
 
         val bestCandidatesByParameterTypes = conflictingCandidates.filter {
@@ -132,9 +207,9 @@ class OverloadingConflictResolver(
     /**
      * `call1` is not less specific than `call2`
      */
-    private fun <D : CallableDescriptor> isNotLessSpecificCallWithArgumentMapping(
+    private fun isNotLessSpecificCallWithArgumentMapping(
-            call1: FlatSignature<MutableResolvedCall<D>>,
+            call1: FlatSignature<C>,
-            call2: FlatSignature<MutableResolvedCall<D>>,
+            call2: FlatSignature<C>,
             discriminateGenerics: Boolean
     ): Boolean {
         return tryCompareDescriptorsFromScripts(call1.candidateDescriptor(), call2.candidateDescriptor()) ?:
@@ -145,9 +220,9 @@ class OverloadingConflictResolver(
      * Returns `true` if `d1` is definitely not less specific than `d2`,
      * `false` otherwise.
      */
-    private fun <D : CallableDescriptor> compareCallsByUsedArguments(
+    private fun compareCallsByUsedArguments(
-            call1: FlatSignature<MutableResolvedCall<D>>,
+            call1: FlatSignature<C>,
-            call2: FlatSignature<MutableResolvedCall<D>>,
+            call2: FlatSignature<C>,
             discriminateGenerics: Boolean
     ): Boolean {
         if (discriminateGenerics) {
@@ -188,9 +263,9 @@ class OverloadingConflictResolver(
         }
     }
 
-    private fun <D: CallableDescriptor> isOfNotLessSpecificShape(
+    private fun isOfNotLessSpecificShape(
-            call1: FlatSignature<MutableResolvedCall<D>>,
+            call1: FlatSignature<C>,
-            call2: FlatSignature<MutableResolvedCall<D>>
+            call2: FlatSignature<C>
     ): Boolean {
         val hasVarargs1 = call1.hasVarargs
         val hasVarargs2 = call2.hasVarargs
@@ -204,9 +279,9 @@ class OverloadingConflictResolver(
         return true
     }
 
-    private fun <D: CallableDescriptor> isOfNotLessSpecificVisibilityForDebugger(
+    private fun isOfNotLessSpecificVisibilityForDebugger(
-            call1: FlatSignature<MutableResolvedCall<D>>,
+            call1: FlatSignature<C>,
-            call2: FlatSignature<MutableResolvedCall<D>>,
+            call2: FlatSignature<C>,
             isDebuggerContext: Boolean
     ): Boolean {
         if (isDebuggerContext) {
@@ -254,34 +329,16 @@ class OverloadingConflictResolver(
             tryCompareDescriptorsFromScripts(f, g) ?:
             isNotLessSpecificCallableReferenceDescriptor(f, g)
 
-    // Different smartcasts may lead to the same candidate descriptor wrapped into different ResolvedCallImpl objects
+    // Different smart casts may lead to the same candidate descriptor wrapped into different ResolvedCallImpl objects
-    private fun <D : CallableDescriptor> uniquifyCandidatesSet(candidates: Collection<MutableResolvedCall<D>>): Set<MutableResolvedCall<D>> =
+    private fun uniquifyCandidatesSet(candidates: Collection<C>): Set<C> =
-            THashSet<MutableResolvedCall<D>>(candidates.size, getCallHashingStrategy<MutableResolvedCall<D>>()).apply { addAll(candidates) }
+            THashSet(candidates.size, resolvedCallHashingStrategy).apply { addAll(candidates) }
 
-    private fun <C> newResolvedCallSet(expectedSize: Int): MutableSet<C> =
+    private fun newResolvedCallSet(expectedSize: Int): MutableSet<C> =
-            THashSet<C>(expectedSize, getCallHashingStrategy<C>())
+            THashSet(expectedSize, resolvedCallHashingStrategy)
 
-    private object ResolvedCallHashingStrategy : TObjectHashingStrategy<ResolvedCall<*>> {
+    private fun FlatSignature<C>.candidateDescriptor() =
-        override fun equals(call1: ResolvedCall<*>?, call2: ResolvedCall<*>?): Boolean =
-                if (call1 != null && call2 != null)
-                    call1.resultingDescriptor == call2.resultingDescriptor
-                else
-                    call1 == call2
-
-        override fun computeHashCode(call: ResolvedCall<*>?): Int =
-                call?.resultingDescriptor?.hashCode() ?: 0
-    }
-
-    private val MutableResolvedCall<*>.resultingVariableDescriptor: VariableDescriptor
-        get() = (this as VariableAsFunctionResolvedCall).variableCall.resultingDescriptor
-
-    @Suppress("UNCHECKED_CAST")
-    private fun <C> getCallHashingStrategy() =
-            ResolvedCallHashingStrategy as TObjectHashingStrategy<C>
-
-    private fun <D : CallableDescriptor> FlatSignature<ResolvedCall<D>>.candidateDescriptor() =
             origin.resultingDescriptor.original
 
-    private fun <D : CallableDescriptor> FlatSignature<ResolvedCall<D>>.descriptorVisibility() =
+    private fun FlatSignature<C>.descriptorVisibility() =
             candidateDescriptor().visibility
 }

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/results/ResolutionResultsHandler.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2015 JetBrains s.r.o.
+ * Copyright 2010-2016 JetBrains s.r.o.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -17,46 +17,31 @@
 package org.jetbrains.kotlin.resolve.calls.results;
 
 import com.google.common.collect.Sets;
-import kotlin.collections.CollectionsKt;
-import kotlin.jvm.functions.Function1;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.kotlin.builtins.KotlinBuiltIns;
 import org.jetbrains.kotlin.descriptors.CallableDescriptor;
 import org.jetbrains.kotlin.resolve.BindingTrace;
-import org.jetbrains.kotlin.resolve.DescriptorEquivalenceForOverrides;
-import org.jetbrains.kotlin.resolve.DescriptorToSourceUtils;
-import org.jetbrains.kotlin.resolve.OverridingUtil;
 import org.jetbrains.kotlin.resolve.calls.callUtil.CallUtilKt;
 import org.jetbrains.kotlin.resolve.calls.context.CallResolutionContext;
 import org.jetbrains.kotlin.resolve.calls.context.CheckArgumentTypesMode;
 import org.jetbrains.kotlin.resolve.calls.model.MutableResolvedCall;
-import org.jetbrains.kotlin.resolve.calls.model.VariableAsFunctionResolvedCall;
 import org.jetbrains.kotlin.resolve.calls.tasks.TracingStrategy;
 
-import java.util.*;
+import java.util.Collection;
+import java.util.EnumSet;
+import java.util.Set;
 
 import static org.jetbrains.kotlin.resolve.calls.results.ResolutionStatus.*;
 
 public class ResolutionResultsHandler {
-    private static final Function1<MutableResolvedCall<?>, CallableDescriptor> MAP_RESOLVED_CALL_TO_RESULTING_DESCRIPTOR =
-            new Function1<MutableResolvedCall<?>, CallableDescriptor>() {
-                @Override
-                public CallableDescriptor invoke(MutableResolvedCall<?> resolvedCall) {
-                    return resolvedCall.getResultingDescriptor();
-                }
-            };
 
-    private static final Function1<MutableResolvedCall<?>, Integer> MAP_RESOLVED_CALL_TO_SOURCE_PRESENCE =
+    private final OverloadingConflictResolver<MutableResolvedCall<?>> overloadingConflictResolver;
-            new Function1<MutableResolvedCall<?>, Integer>() {
-                @Override
-                public Integer invoke(MutableResolvedCall<?> resolvedCall) {
-                    return DescriptorToSourceUtils.descriptorToDeclaration(resolvedCall.getResultingDescriptor()) != null ? 0 : 1;
-                }
-            };
 
-    private final OverloadingConflictResolver overloadingConflictResolver;
+    public ResolutionResultsHandler(
-
+            @NotNull KotlinBuiltIns builtIns,
-    public ResolutionResultsHandler(@NotNull OverloadingConflictResolver overloadingConflictResolver) {
+            @NotNull TypeSpecificityComparator specificityComparator
-        this.overloadingConflictResolver = overloadingConflictResolver;
+    ) {
+        overloadingConflictResolver = FlatSignatureSpecificityKt.createOverloadingConflictResolver(builtIns, specificityComparator);
     }
 
     @NotNull
@@ -195,35 +180,6 @@ public class ResolutionResultsHandler {
         return true;
     }
 
-    // Sometimes we should compare "copies" from sources and from binary files.
-    // But we cannot compare return types for such copies, because it may lead us to recursive problem (see KT-11995).
-    // Because of this we compare them without return type and choose descriptor from source if we found duplicate.
-    @NotNull
-    private static <D extends CallableDescriptor> Set<MutableResolvedCall<D>> filterOutEquivalentCalls(
-            @NotNull Set<MutableResolvedCall<D>> candidates
-    ) {
-        if (candidates.size() <= 1) return candidates;
-
-        List<MutableResolvedCall<D>> fromSourcesGoesFirst = CollectionsKt.sortedBy(candidates, MAP_RESOLVED_CALL_TO_SOURCE_PRESENCE);
-
-        Set<MutableResolvedCall<D>> result = new LinkedHashSet<MutableResolvedCall<D>>();
-        outerLoop:
-        for (MutableResolvedCall<D> meD : fromSourcesGoesFirst) {
-            for (MutableResolvedCall<D> otherD : result) {
-                D me = meD.getResultingDescriptor();
-                D other = otherD.getResultingDescriptor();
-                boolean ignoreReturnType = (DescriptorToSourceUtils.descriptorToDeclaration(me) == null) !=
-                                           (DescriptorToSourceUtils.descriptorToDeclaration(other) == null);
-                if (DescriptorEquivalenceForOverrides.INSTANCE.areCallableDescriptorsEquivalent(me, other, ignoreReturnType)) {
-                    continue outerLoop;
-                }
-            }
-            result.add(meD);
-        }
-
-        return result;
-    }
-
     @NotNull
     private <D extends CallableDescriptor> OverloadResolutionResultsImpl<D> chooseAndReportMaximallySpecific(
             @NotNull Set<MutableResolvedCall<D>> candidates,
@@ -231,34 +187,16 @@ public class ResolutionResultsHandler {
             boolean isDebuggerContext,
             @NotNull CheckArgumentTypesMode checkArgumentsMode
     ) {
-        if (candidates.size() == 1) {
+        OverloadingConflictResolver<MutableResolvedCall<D>> myResolver = (OverloadingConflictResolver) overloadingConflictResolver;
-            return OverloadResolutionResultsImpl.success(candidates.iterator().next());
-        }
 
-        if (candidates.iterator().next() instanceof VariableAsFunctionResolvedCall) {
+        Set<MutableResolvedCall<D>> specificCalls =
-            candidates = overloadingConflictResolver.findMaximallySpecificVariableAsFunctionCalls(candidates);
+                myResolver.chooseMaximallySpecificCandidates(candidates, checkArgumentsMode, discriminateGenerics, isDebuggerContext);
-        }
 
-        Set<MutableResolvedCall<D>> noEquivalentCalls = filterOutEquivalentCalls(candidates);
+        if (specificCalls.size() == 1) {
-        Set<MutableResolvedCall<D>> noOverrides =
+            return OverloadResolutionResultsImpl.success(specificCalls.iterator().next());
-                OverridingUtil.filterOverrides(noEquivalentCalls, MAP_RESOLVED_CALL_TO_RESULTING_DESCRIPTOR);
-        if (noOverrides.size() == 1) {
-            return OverloadResolutionResultsImpl.success(noOverrides.iterator().next());
         }
-
+        else {
-        MutableResolvedCall<D> maximallySpecific = overloadingConflictResolver.findMaximallySpecific(noOverrides, checkArgumentsMode, false, isDebuggerContext);
+            return OverloadResolutionResultsImpl.ambiguity(specificCalls);
-        if (maximallySpecific != null) {
-            return OverloadResolutionResultsImpl.success(maximallySpecific);
         }
-
-        if (discriminateGenerics) {
-            MutableResolvedCall<D> maximallySpecificGenericsDiscriminated = overloadingConflictResolver.findMaximallySpecific(
-                    noOverrides, checkArgumentsMode, true, isDebuggerContext);
-            if (maximallySpecificGenericsDiscriminated != null) {
-                return OverloadResolutionResultsImpl.success(maximallySpecificGenericsDiscriminated);
-            }
-        }
-
-        return OverloadResolutionResultsImpl.ambiguity(noOverrides);
     }
 }