Minor, get rid of AlternativeMethodSignature in irrelevant place

core/descriptor.loader.java/src/org/jetbrains/kotlin/load/java/components/ExternalSignatureResolver.java

@@ -60,7 +60,7 @@ public interface ExternalSignatureResolver {
         private final boolean hasStableParameterNames;
 
         public AlternativeMethodSignature(
-                @Nullable KotlinType returnType,
+                @NotNull KotlinType returnType,
                 @Nullable KotlinType receiverType,
                 @NotNull List<ValueParameterDescriptor> valueParameters,
                 @NotNull List<TypeParameterDescriptor> typeParameters,
@@ -75,7 +75,7 @@ public interface ExternalSignatureResolver {
             this.hasStableParameterNames = hasStableParameterNames;
         }
 
-        @Nullable
+        @NotNull
         public KotlinType getReturnType() {
             return returnType;
         }

core/descriptor.loader.java/src/org/jetbrains/kotlin/load/java/lazy/descriptors/LazyJavaClassMemberScope.kt

@@ -30,7 +30,6 @@ import org.jetbrains.kotlin.load.java.BuiltinMethodsWithDifferentJvmName.sameAsR
 import org.jetbrains.kotlin.load.java.BuiltinMethodsWithSpecialGenericSignature.sameAsBuiltinMethodWithErasedValueParameters
 import org.jetbrains.kotlin.load.java.BuiltinSpecialProperties.getBuiltinSpecialPropertyGetterName
 import org.jetbrains.kotlin.load.java.components.DescriptorResolverUtils
-import org.jetbrains.kotlin.load.java.components.ExternalSignatureResolver
 import org.jetbrains.kotlin.load.java.components.TypeUsage
 import org.jetbrains.kotlin.load.java.descriptors.JavaConstructorDescriptor
 import org.jetbrains.kotlin.load.java.descriptors.JavaMethodDescriptor
@@ -421,12 +420,15 @@ public class LazyJavaClassMemberScope(
 
     override fun resolveMethodSignature(
             method: JavaMethod, methodTypeParameters: List<TypeParameterDescriptor>, returnType: KotlinType,
-            valueParameters: LazyJavaScope.ResolvedValueParameters
+            valueParameters: List<ValueParameterDescriptor>
     ): LazyJavaScope.MethodSignatureData {
         val propagated = c.components.externalSignatureResolver.resolvePropagatedSignature(
-                method, ownerDescriptor, returnType, null, valueParameters.descriptors, methodTypeParameters
+                method, ownerDescriptor, returnType, null, valueParameters, methodTypeParameters
+        )
+        return LazyJavaScope.MethodSignatureData(
+                propagated.returnType, propagated.receiverType, propagated.valueParameters, propagated.typeParameters,
+                propagated.hasStableParameterNames(), propagated.errors
         )
-        return LazyJavaScope.MethodSignatureData(propagated, propagated.errors)
     }
 
     private fun hasOverriddenBuiltinFunctionWithErasedValueParameters(

core/descriptor.loader.java/src/org/jetbrains/kotlin/load/java/lazy/descriptors/LazyJavaScope.kt

@@ -23,7 +23,6 @@ import org.jetbrains.kotlin.descriptors.impl.ValueParameterDescriptorImpl
 import org.jetbrains.kotlin.incremental.components.LookupLocation
 import org.jetbrains.kotlin.incremental.components.NoLookupLocation
 import org.jetbrains.kotlin.incremental.record
-import org.jetbrains.kotlin.load.java.components.ExternalSignatureResolver
 import org.jetbrains.kotlin.load.java.components.TypeUsage
 import org.jetbrains.kotlin.load.java.descriptors.JavaMethodDescriptor
 import org.jetbrains.kotlin.load.java.descriptors.JavaPropertyDescriptor
@@ -97,7 +96,11 @@ public abstract class LazyJavaScope(protected val c: LazyJavaResolverContext) :
     open protected fun JavaMethodDescriptor.isVisibleAsFunction() = true
 
     protected data class MethodSignatureData(
-            val effectiveSignature: ExternalSignatureResolver.AlternativeMethodSignature,
+            val returnType: KotlinType,
+            val receiverType: KotlinType?,
+            val valueParameters: List<ValueParameterDescriptor>,
+            val typeParameters: List<TypeParameterDescriptor>,
+            val hasStableParameterNames: Boolean,
             val errors: List<String>
     )
 
@@ -105,7 +108,8 @@ public abstract class LazyJavaScope(protected val c: LazyJavaResolverContext) :
             method: JavaMethod,
             methodTypeParameters: List<TypeParameterDescriptor>,
             returnType: KotlinType,
-            valueParameters: ResolvedValueParameters): MethodSignatureData
+            valueParameters: List<ValueParameterDescriptor>
+    ): MethodSignatureData
 
     fun resolveMethodToFunctionDescriptor(method: JavaMethod): JavaMethodDescriptor {
         val annotations = c.resolveAnnotations(method)
@@ -120,22 +124,22 @@ public abstract class LazyJavaScope(protected val c: LazyJavaResolverContext) :
 
         val returnType = computeMethodReturnType(method, annotations, c)
 
-        val (effectiveSignature, signatureErrors) = resolveMethodSignature(method, methodTypeParameters, returnType, valueParameters)
+        val effectiveSignature = resolveMethodSignature(method, methodTypeParameters, returnType, valueParameters.descriptors)
 
         functionDescriptorImpl.initialize(
-                effectiveSignature.getReceiverType(),
+                effectiveSignature.receiverType,
                 getDispatchReceiverParameter(),
-                effectiveSignature.getTypeParameters(),
-                effectiveSignature.getValueParameters(),
-                effectiveSignature.getReturnType(),
+                effectiveSignature.typeParameters,
+                effectiveSignature.valueParameters,
+                effectiveSignature.returnType,
                 Modality.convertFromFlags(method.isAbstract(), !method.isFinal()),
                 method.getVisibility()
         )
 
-        functionDescriptorImpl.setParameterNamesStatus(effectiveSignature.hasStableParameterNames(), valueParameters.hasSynthesizedNames)
+        functionDescriptorImpl.setParameterNamesStatus(effectiveSignature.hasStableParameterNames, valueParameters.hasSynthesizedNames)
 
-        if (signatureErrors.isNotEmpty()) {
-            c.components.externalSignatureResolver.reportSignatureErrors(functionDescriptorImpl, signatureErrors)
+        if (effectiveSignature.errors.isNotEmpty()) {
+            c.components.externalSignatureResolver.reportSignatureErrors(functionDescriptorImpl, effectiveSignature.errors)
         }
 
         return functionDescriptorImpl

core/descriptor.loader.java/src/org/jetbrains/kotlin/load/java/lazy/descriptors/LazyJavaStaticScope.kt

@@ -18,7 +18,7 @@ package org.jetbrains.kotlin.load.java.lazy.descriptors
 
 import org.jetbrains.kotlin.descriptors.PropertyDescriptor
 import org.jetbrains.kotlin.descriptors.TypeParameterDescriptor
-import org.jetbrains.kotlin.load.java.components.ExternalSignatureResolver
+import org.jetbrains.kotlin.descriptors.ValueParameterDescriptor
 import org.jetbrains.kotlin.load.java.lazy.LazyJavaResolverContext
 import org.jetbrains.kotlin.load.java.structure.JavaMethod
 import org.jetbrains.kotlin.name.FqName
@@ -31,17 +31,13 @@ public abstract class LazyJavaStaticScope(c: LazyJavaResolverContext) : LazyJava
 
     // Package fragments are not nested
     override fun getPackage(name: Name) = null
+
     abstract fun getSubPackages(): Collection<FqName>
 
     override fun resolveMethodSignature(
             method: JavaMethod, methodTypeParameters: List<TypeParameterDescriptor>, returnType: KotlinType,
-            valueParameters: LazyJavaScope.ResolvedValueParameters
-    ): LazyJavaScope.MethodSignatureData {
-        val effectiveSignature = ExternalSignatureResolver.AlternativeMethodSignature(
-                returnType, null, valueParameters.descriptors, methodTypeParameters, emptyList<String>(), false
-        )
-        return LazyJavaScope.MethodSignatureData(effectiveSignature, effectiveSignature.getErrors())
-    }
+            valueParameters: List<ValueParameterDescriptor>
+    ) = LazyJavaScope.MethodSignatureData(returnType, null, valueParameters, methodTypeParameters, false, emptyList())
 
     override fun computeNonDeclaredProperties(name: Name, result: MutableCollection<PropertyDescriptor>) {
         //no undeclared properties