Introduce & use resolveToDescriptorIfAny<DescriptorType>

This allows to omit casts after resolveToDescriptorIfAny() call,
get different descriptors for different receivers (in future),
distinguish parameter / property situation for primary constructor

idea/ide-common/src/org/jetbrains/kotlin/idea/caches/resolve/resolutionApi.kt

@@ -22,6 +22,7 @@ import org.jetbrains.kotlin.analyzer.AnalysisResult
 import org.jetbrains.kotlin.caches.resolve.KotlinCacheService
 import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
 import org.jetbrains.kotlin.descriptors.ModuleDescriptor
+import org.jetbrains.kotlin.descriptors.ValueParameterDescriptor
 import org.jetbrains.kotlin.idea.resolve.ResolutionFacade
 import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.psi.*
@@ -56,15 +57,24 @@ fun KtDeclaration.unsafeResolveToDescriptor(bodyResolveMode: BodyResolveMode = B
  * and then takes the relevant descriptor from binding context.
  * The exact set of declarations to resolve depends on bodyResolveMode
  */
-fun KtDeclaration.resolveToDescriptorIfAny(bodyResolveMode: BodyResolveMode = BodyResolveMode.PARTIAL): DeclarationDescriptor? {
+inline fun <reified D : DeclarationDescriptor> KtDeclaration.resolveToDescriptorIfAny(
+    bodyResolveMode: BodyResolveMode = BodyResolveMode.PARTIAL,
+    klass: Class<D> = D::class.java
+): D? {
     //TODO: BodyResolveMode.PARTIAL is not quite safe!
     val context = analyze(bodyResolveMode)
-    if (this is KtParameter && this.hasValOrVar()) {
-        return context.get(BindingContext.PRIMARY_CONSTRUCTOR_PARAMETER, this)
+    if (this is KtParameter && this.hasValOrVar() && klass != ValueParameterDescriptor::class.java) {
+        return context.get(BindingContext.PRIMARY_CONSTRUCTOR_PARAMETER, this) as? D
     }
-    return context.get(BindingContext.DECLARATION_TO_DESCRIPTOR, this)
+    return context.get(BindingContext.DECLARATION_TO_DESCRIPTOR, this) as? D
 }
 
+fun KtDeclaration.resolveToDescriptorIfAny(bodyResolveMode: BodyResolveMode = BodyResolveMode.PARTIAL) =
+    resolveToDescriptorIfAny<DeclarationDescriptor>(bodyResolveMode)
+
+fun KtParameter.resolveToDescriptorIfAny(bodyResolveMode: BodyResolveMode = BodyResolveMode.PARTIAL) =
+    resolveToDescriptorIfAny<ValueParameterDescriptor>(bodyResolveMode)
+
 fun KtFile.resolveImportReference(fqName: FqName): Collection<DeclarationDescriptor> {
     val facade = getResolutionFacade()
     return facade.resolveImportReference(facade.moduleDescriptor, fqName)

idea/idea-analysis/src/org/jetbrains/kotlin/idea/search/usagesSearch/utils.kt

@@ -47,7 +47,7 @@ import org.jetbrains.kotlin.resolve.OverridingUtil
 import org.jetbrains.kotlin.resolve.lazy.BodyResolveMode
 
 val KtDeclaration.descriptor: DeclarationDescriptor?
-    get() = this.resolveToDescriptorIfAny(BodyResolveMode.FULL)
+    get() = if (this is KtParameter) this.descriptor else this.resolveToDescriptorIfAny(BodyResolveMode.FULL)
 
 val KtDeclaration.constructor: ConstructorDescriptor?
     get() {
@@ -59,8 +59,11 @@ val KtDeclaration.constructor: ConstructorDescriptor?
         }
     }
 
+val KtParameter.descriptor: ValueParameterDescriptor?
+    get() = this.resolveToDescriptorIfAny<ValueParameterDescriptor>(BodyResolveMode.FULL)
+
 val KtParameter.propertyDescriptor: PropertyDescriptor?
-    get() = this.analyze().get(BindingContext.PRIMARY_CONSTRUCTOR_PARAMETER, this)
+    get() = this.resolveToDescriptorIfAny<PropertyDescriptor>(BodyResolveMode.FULL)
 
 fun PsiReference.checkUsageVsOriginalDescriptor(
         targetDescriptor: DeclarationDescriptor,

idea/src/org/jetbrains/kotlin/idea/quickfix/RemoveUnusedFunctionParameterFix.kt

@@ -40,7 +40,7 @@ class RemoveUnusedFunctionParameterFix(parameter: KtParameter) : KotlinQuickFixA
         val element = element ?: return
         val primaryConstructor = element.parent?.parent as? KtPrimaryConstructor
         val parameterList = element.parent as? KtParameterList
-        val parameterDescriptor = element.resolveToDescriptorIfAny(BodyResolveMode.FULL) as? ValueParameterDescriptor ?: return
+        val parameterDescriptor = element.resolveToDescriptorIfAny(BodyResolveMode.FULL) ?: return
         ChangeFunctionSignatureFix.runRemoveParameter(parameterDescriptor, element)
         val nextParameter = parameterList?.parameters?.getOrNull(parameterDescriptor.index)
         if (nextParameter != null) {

idea/src/org/jetbrains/kotlin/idea/slicer/Slicer.kt

@@ -41,9 +41,7 @@ import org.jetbrains.kotlin.cfg.pseudocode.instructions.eval.*
 import org.jetbrains.kotlin.cfg.pseudocode.instructions.jumps.ReturnValueInstruction
 import org.jetbrains.kotlin.cfg.pseudocodeTraverser.TraversalOrder
 import org.jetbrains.kotlin.cfg.pseudocodeTraverser.traverse
-import org.jetbrains.kotlin.descriptors.CallableMemberDescriptor
-import org.jetbrains.kotlin.descriptors.DeclarationDescriptorWithSource
-import org.jetbrains.kotlin.descriptors.VariableDescriptorWithAccessors
+import org.jetbrains.kotlin.descriptors.*
 import org.jetbrains.kotlin.descriptors.impl.SyntheticFieldDescriptor
 import org.jetbrains.kotlin.idea.caches.resolve.*
 import org.jetbrains.kotlin.idea.core.isOverridable