Refactoring. Move specificity relations into TypeSpecificityComparator component.

compiler/frontend.java/src/org/jetbrains/kotlin/resolve/jvm/JvmTypeSpecificityComparator.kt

@@ -0,0 +1,46 @@
+/*
+ * 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.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.jetbrains.kotlin.resolve.jvm
+
+import org.jetbrains.kotlin.builtins.KotlinBuiltIns
+import org.jetbrains.kotlin.resolve.calls.results.TypeSpecificityComparator
+import org.jetbrains.kotlin.types.KotlinType
+import org.jetbrains.kotlin.types.flexibility
+import org.jetbrains.kotlin.types.isFlexible
+
+object JvmTypeSpecificityComparator : TypeSpecificityComparator {
+
+    override fun isDefinitelyLessSpecific(specific: KotlinType, general: KotlinType): Boolean {
+        if (!specific.isFlexible() || general.isFlexible()) return false
+
+        // general is inflexible
+        val flexibility = specific.flexibility()
+
+        // For primitive types we have to take care of the case when there are two overloaded methods like
+        //    foo(int) and foo(Integer)
+        // if we do not discriminate one of them, any call to foo(kotlin.Int) will result in overload resolution ambiguity
+        // so, for such cases, we discriminate Integer in favour of int
+        if (!KotlinBuiltIns.isPrimitiveType(general) || !KotlinBuiltIns.isPrimitiveType(flexibility.lowerBound)) {
+            return false
+        }
+
+        // Int? >< Int!
+        if (general.isMarkedNullable) return false
+        // Int! lessSpecific Int
+        return true
+    }
+}

compiler/frontend.java/src/org/jetbrains/kotlin/resolve/jvm/platform/JvmPlatformConfigurator.kt

@@ -18,11 +18,13 @@ package org.jetbrains.kotlin.resolve.jvm.platform
 
 import org.jetbrains.kotlin.container.StorageComponentContainer
 import org.jetbrains.kotlin.container.useImpl
+import org.jetbrains.kotlin.container.useInstance
 import org.jetbrains.kotlin.jvm.RuntimeAssertionsTypeChecker
 import org.jetbrains.kotlin.load.kotlin.JavaAnnotationCallChecker
 import org.jetbrains.kotlin.load.kotlin.nativeDeclarations.NativeFunChecker
 import org.jetbrains.kotlin.resolve.PlatformConfigurator
 import org.jetbrains.kotlin.resolve.jvm.JvmOverloadFilter
+import org.jetbrains.kotlin.resolve.jvm.JvmTypeSpecificityComparator
 import org.jetbrains.kotlin.resolve.jvm.checkers.*
 import org.jetbrains.kotlin.synthetic.JavaSyntheticScopes
 import org.jetbrains.kotlin.types.DynamicTypesSettings
@@ -79,5 +81,6 @@ object JvmPlatformConfigurator : PlatformConfigurator(
 
         container.useImpl<ReflectionAPICallChecker>()
         container.useImpl<JavaSyntheticScopes>()
+        container.useInstance(JvmTypeSpecificityComparator)
     }
 }