Improve implementation of callable reference superclasses

Previously to use reflection on them, you had to wrap an already created object
with a "Reflection.function" or "Reflection.propertyN" call, which the JVM
back-end was doing. This was not optimal in several senses and current solution
fixes that

core/reflection.jvm/src/kotlin/reflect/jvm/KCallablesJvm.kt

@@ -22,7 +22,7 @@ import kotlin.reflect.KCallable
 import kotlin.reflect.KFunction
 import kotlin.reflect.KMutableProperty
 import kotlin.reflect.KProperty
-import kotlin.reflect.jvm.internal.KCallableImpl
+import kotlin.reflect.jvm.internal.asKCallableImpl
 
 /**
  * Provides a way to suppress JVM access checks for a callable.
@@ -53,7 +53,7 @@ public var KCallable<*>.isAccessible: Boolean
                 javaMethod?.isAccessible ?: true
             is KFunction ->
                 javaMethod?.isAccessible ?: true &&
-                ((this as? KCallableImpl<*>)?.defaultCaller?.member as? AccessibleObject)?.isAccessible ?: true &&
+                (this.asKCallableImpl()?.defaultCaller?.member as? AccessibleObject)?.isAccessible ?: true &&
                 this.javaConstructor?.isAccessible ?: true
             else -> throw UnsupportedOperationException("Unknown callable: $this ($javaClass)")
         }
@@ -79,7 +79,7 @@ public var KCallable<*>.isAccessible: Boolean
             }
             is KFunction -> {
                 javaMethod?.isAccessible = value
-                ((this as? KCallableImpl<*>)?.defaultCaller?.member as? AccessibleObject)?.isAccessible = true
+                (this.asKCallableImpl()?.defaultCaller?.member as? AccessibleObject)?.isAccessible = true
                 this.javaConstructor?.isAccessible = value
             }
             else -> throw UnsupportedOperationException("Unknown callable: $this ($javaClass)")

core/reflection.jvm/src/kotlin/reflect/jvm/ReflectJvmMapping.kt

@@ -23,8 +23,9 @@ import kotlin.jvm.internal.KotlinFileFacade
 import kotlin.jvm.internal.Reflection
 import kotlin.reflect.*
 import kotlin.reflect.jvm.internal.KCallableImpl
-import kotlin.reflect.jvm.internal.KPropertyImpl
 import kotlin.reflect.jvm.internal.KTypeImpl
+import kotlin.reflect.jvm.internal.asKCallableImpl
+import kotlin.reflect.jvm.internal.asKPropertyImpl
 
 // Kotlin reflection -> Java reflection
 
@@ -33,7 +34,7 @@ import kotlin.reflect.jvm.internal.KTypeImpl
  * or `null` if the property has no backing field.
  */
 public val KProperty<*>.javaField: Field?
-    get() = (this as? KPropertyImpl<*>)?.javaField
+    get() = this.asKPropertyImpl()?.javaField
 
 /**
  * Returns a Java [Method] instance corresponding to the getter of the given property,
@@ -55,7 +56,7 @@ public val KMutableProperty<*>.javaSetter: Method?
  * or `null` if this function is a constructor or cannot be represented by a Java [Method].
  */
 public val KFunction<*>.javaMethod: Method?
-    get() = (this as? KCallableImpl<*>)?.caller?.member as? Method
+    get() = this.asKCallableImpl()?.caller?.member as? Method
 
 /**
  * Returns a Java [Constructor] instance corresponding to the given Kotlin function,
@@ -63,7 +64,7 @@ public val KFunction<*>.javaMethod: Method?
  */
 @Suppress("UNCHECKED_CAST")
 public val <T> KFunction<T>.javaConstructor: Constructor<T>?
-    get() = (this as? KCallableImpl<T>)?.caller?.member as? Constructor<T>
+    get() = this.asKCallableImpl()?.caller?.member as? Constructor<T>
 
 
 /**

core/reflection.jvm/src/kotlin/reflect/jvm/internal/DescriptorBasedProperty.kt

@@ -19,13 +19,14 @@ package kotlin.reflect.jvm.internal
 import org.jetbrains.kotlin.descriptors.PropertyDescriptor
 import org.jetbrains.kotlin.serialization.jvm.JvmProtoBufUtil
 import java.lang.reflect.Field
+import kotlin.reflect.KProperty
 import kotlin.reflect.jvm.internal.JvmPropertySignature.JavaField
 import kotlin.reflect.jvm.internal.JvmPropertySignature.KotlinProperty
 
 internal abstract class DescriptorBasedProperty<out R> protected constructor(
         val container: KDeclarationContainerImpl,
         name: String,
-        signature: String,
+        val signature: String,
         descriptorInitialValue: PropertyDescriptor?
 ) : KCallableImpl<R> {
     constructor(container: KDeclarationContainerImpl, name: String, signature: String) : this(
@@ -55,11 +56,13 @@ internal abstract class DescriptorBasedProperty<out R> protected constructor(
         }
     }
 
-    override fun equals(other: Any?): Boolean =
-            other is DescriptorBasedProperty<*> && descriptor == other.descriptor
+    override fun equals(other: Any?): Boolean {
+        val that = other.asKPropertyImpl() ?: return false
+        return container == that.container && name == that.name && signature == that.signature
+    }
 
     override fun hashCode(): Int =
-            descriptor.hashCode()
+            (container.hashCode() * 31 + name.hashCode()) * 31 + signature.hashCode()
 
     override fun toString(): String =
             ReflectionObjectRenderer.renderProperty(descriptor)

core/reflection.jvm/src/kotlin/reflect/jvm/internal/KFunctionImpl.kt

@@ -30,7 +30,7 @@ import kotlin.reflect.jvm.internal.JvmFunctionSignature.*
 internal open class KFunctionImpl protected constructor(
         private val container: KDeclarationContainerImpl,
         name: String,
-        signature: String,
+        private val signature: String,
         descriptorInitialValue: FunctionDescriptor?
 ) : KFunction<Any?>, KCallableImpl<Any?>, FunctionImpl() {
     constructor(container: KDeclarationContainerImpl, name: String, signature: String) : this(container, name, signature, null)
@@ -104,11 +104,13 @@ internal open class KFunctionImpl protected constructor(
                (if (descriptor.extensionReceiverParameter != null) 1 else 0)
     }
 
-    override fun equals(other: Any?): Boolean =
-            other is KFunctionImpl && descriptor == other.descriptor
+    override fun equals(other: Any?): Boolean {
+        val that = other.asKFunctionImpl() ?: return false
+        return container == that.container && name == that.name && signature == that.signature
+    }
 
     override fun hashCode(): Int =
-            descriptor.hashCode()
+            (container.hashCode() * 31 + name.hashCode()) * 31 + signature.hashCode()
 
     override fun toString(): String =
             ReflectionObjectRenderer.renderFunction(descriptor)

core/reflection.jvm/src/kotlin/reflect/jvm/internal/KPropertyImpl.kt

@@ -33,6 +33,8 @@ internal interface KPropertyImpl<out R> : KProperty<R>, KCallableImpl<R> {
 
     val container: KDeclarationContainerImpl
 
+    val signature: String
+
     override val getter: Getter<R>
 
     override val descriptor: PropertyDescriptor

core/reflection.jvm/src/kotlin/reflect/jvm/internal/util.kt

@@ -17,6 +17,8 @@
 package kotlin.reflect.jvm.internal
 
 import org.jetbrains.kotlin.name.FqName
+import kotlin.jvm.internal.FunctionReference
+import kotlin.jvm.internal.PropertyReference
 import kotlin.reflect.IllegalCallableAccessException
 
 internal val JVM_STATIC = FqName("kotlin.jvm.JvmStatic")
@@ -29,3 +31,14 @@ internal inline fun <R> reflectionCall(block: () -> R): R =
         catch (e: IllegalAccessException) {
             throw IllegalCallableAccessException(e)
         }
+
+internal fun Any?.asKFunctionImpl(): KFunctionImpl? =
+        this as? KFunctionImpl ?:
+        (this as? FunctionReference)?.compute() as? KFunctionImpl //
+
+internal fun Any?.asKPropertyImpl(): KPropertyImpl<*>? =
+        this as? KPropertyImpl<*> ?:
+        (this as? PropertyReference)?.compute() as? KPropertyImpl
+
+internal fun Any?.asKCallableImpl(): KCallableImpl<*>? =
+        this as? KCallableImpl<*> ?: asKFunctionImpl() ?: asKPropertyImpl()