Use descriptors for reflection on top level properties

This also allows to obtain a Field object from the package part (see
mapping.kt)

compiler/testData/codegen/boxWithStdlib/callableReference/property/platformNamedAccessors.kt

@@ -0,0 +1,24 @@
+import kotlin.platform.platformName
+import kotlin.reflect.jvm.*
+
+var state: String = "value"
+    [platformName("getter")]
+    get
+    [platformName("setter")]
+    set
+
+fun box(): String {
+    val p = ::state
+
+    if (p.name != "state") return "Fail name: ${p.name}"
+    if (p.get() != "value") return "Fail get: ${p.get()}"
+    p.set("OK")
+
+    val getterName = p.javaGetter!!.getName()
+    if (getterName != "getter") return "Fail getter name: $getterName"
+
+    val setterName = p.javaSetter!!.getName()
+    if (setterName != "setter") return "Fail setter name: $setterName"
+
+    return p.get()
+}

compiler/testData/codegen/boxWithStdlib/reflection/mapping/topLevelProperty.kt

@@ -6,8 +6,9 @@ var topLevel = "123"
 fun box(): String {
     val p = ::topLevel
 
-    // TODO: uncomment when fields are loaded from package parts
-    // assert(p.javaField != null, "Fail p field")
+    assert(p.javaField != null, "Fail p field")
+    val field = p.javaField!!
+    assert(field.getDeclaringClass().getName() contains "_DefaultPackage\$", "Fail field not in package part: ${field.getDeclaringClass()}")
 
     val getter = p.javaGetter!!
     val setter = p.javaSetter!!

compiler/tests/org/jetbrains/kotlin/codegen/generated/BlackBoxWithStdlibCodegenTestGenerated.java

@@ -789,6 +789,12 @@ public class BlackBoxWithStdlibCodegenTestGenerated extends AbstractBlackBoxCode
                 doTestWithStdlib(fileName);
             }
 
+            @TestMetadata("platformNamedAccessors.kt")
+            public void testPlatformNamedAccessors() throws Exception {
+                String fileName = JetTestUtils.navigationMetadata("compiler/testData/codegen/boxWithStdlib/callableReference/property/platformNamedAccessors.kt");
+                doTestWithStdlib(fileName);
+            }
+
             @TestMetadata("privateClassVal.kt")
             public void testPrivateClassVal() throws Exception {
                 String fileName = JetTestUtils.navigationMetadata("compiler/testData/codegen/boxWithStdlib/callableReference/property/privateClassVal.kt");

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

@@ -50,16 +50,16 @@ abstract class DescriptorBasedProperty(computeDescriptor: () -> PropertyDescript
     val field: Field? by ReflectProperties.lazySoft {
         val proto = protoData
         if (!proto.signature.hasField()) null
-        else container.findFieldBySignature(proto.signature.getField(), proto.nameResolver)
+        else container.findFieldBySignature(proto.proto, proto.signature.getField(), proto.nameResolver)
     }
 
-    val getter: Method? by ReflectProperties.lazySoft {
+    open val getter: Method? by ReflectProperties.lazySoft {
         val proto = protoData
         if (!proto.signature.hasGetter()) null
         else container.findMethodBySignature(proto.signature.getGetter(), proto.nameResolver)
     }
 
-    val setter: Method? by ReflectProperties.lazySoft {
+    open val setter: Method? by ReflectProperties.lazySoft {
         val proto = protoData
         if (!proto.signature.hasSetter()) null
         else container.findMethodBySignature(proto.signature.getSetter(), proto.nameResolver)

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

@@ -16,12 +16,39 @@
 
 package kotlin.reflect.jvm.internal
 
-import kotlin.reflect.KPackage
+import org.jetbrains.kotlin.load.java.structure.reflect.classId
+import org.jetbrains.kotlin.resolve.scopes.JetScope
 import kotlin.jvm.internal.KotlinPackage
+import kotlin.reflect.*
 
-private val KOTLIN_PACKAGE_ANNOTATION_CLASS = javaClass<KotlinPackage>()
+class KPackageImpl(override val jClass: Class<*>) : KCallableContainerImpl(), KPackage {
+    val descriptor by ReflectProperties.lazySoft {
+        val moduleData = jClass.getOrCreateModule()
+        val fqName = jClass.classId.getPackageFqName()
+
+        moduleData.module.getPackage(fqName) ?: throw KotlinReflectionInternalError("Package not resolved: $fqName")
+    }
+
+    override val scope: JetScope get() = descriptor.getMemberScope()
+
+    fun topLevelVariable(name: String): KTopLevelVariable<*> {
+        val descriptor = findPropertyDescriptor(name)
+        return KTopLevelVariableImpl(this, descriptor)
+    }
+
+    fun mutableTopLevelVariable(name: String): KMutableTopLevelVariable<*> {
+        val descriptor = findPropertyDescriptor(name)
+        return KMutableTopLevelVariableImpl(this, descriptor)
+    }
+
+    fun <T> topLevelExtensionProperty(name: String, receiver: Class<T>): KTopLevelExtensionProperty<T, *> {
+        return KTopLevelExtensionPropertyImpl(name, this, receiver)
+    }
+
+    fun <T> mutableTopLevelExtensionProperty(name: String, receiver: Class<T>): KMutableTopLevelExtensionProperty<T, *> {
+        return KMutableTopLevelExtensionPropertyImpl(name, this, receiver)
+    }
 
-class KPackageImpl(val jClass: Class<*>) : KPackage {
     override fun equals(other: Any?): Boolean =
             other is KPackageImpl && jClass == other.jClass
 
@@ -30,7 +57,7 @@ class KPackageImpl(val jClass: Class<*>) : KPackage {
 
     override fun toString(): String {
         val name = jClass.getName()
-        return "package " + if (jClass.isAnnotationPresent(KOTLIN_PACKAGE_ANNOTATION_CLASS)) {
+        return "package " + if (jClass.isAnnotationPresent(javaClass<KotlinPackage>())) {
             if (name == "_DefaultPackage") "<default>" else name.substringBeforeLast(".")
         }
         else name

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

@@ -16,27 +16,24 @@
 
 package kotlin.reflect.jvm.internal
 
-import java.lang.reflect.*
-import kotlin.reflect.*
+import org.jetbrains.kotlin.descriptors.PropertyDescriptor
+import java.lang.reflect.Method
+import kotlin.reflect.IllegalPropertyAccessException
+import kotlin.reflect.KMutableTopLevelVariable
+import kotlin.reflect.KTopLevelVariable
 
 open class KTopLevelVariableImpl<out R>(
-        override val name: String,
-        protected val owner: KPackageImpl
-) : KTopLevelVariable<R>, KVariableImpl<R> {
-    // TODO: load the field from the corresponding package part
-    override val field: Field? get() = null
+        override val container: KPackageImpl,
+        computeDescriptor: () -> PropertyDescriptor
+) : DescriptorBasedProperty(computeDescriptor), KTopLevelVariable<R>, KVariableImpl<R> {
+    override val name: String get() = descriptor.getName().asString()
 
-    // TODO: extract, make lazy (weak?), use our descriptors knowledge, support Java fields
-    override val getter: Method = try {
-        owner.jClass.getMethod(getterName(name))
-    }
-    catch (e: NoSuchMethodException) {
-        throw NoSuchPropertyException(e)
-    }
+    override val getter: Method get() = super<DescriptorBasedProperty>.getter!!
 
     override fun get(): R {
         try {
-            return getter(null) as R
+            [suppress("UNCHECKED_CAST")]
+            return getter.invoke(null) as R
         }
         catch (e: IllegalAccessException) {
             throw IllegalPropertyAccessException(e)
@@ -44,26 +41,20 @@ open class KTopLevelVariableImpl<out R>(
     }
 
     override fun equals(other: Any?): Boolean =
-            other is KTopLevelVariableImpl<*> && name == other.name && owner == other.owner
+            other is KTopLevelVariableImpl<*> && descriptor == other.descriptor
 
     override fun hashCode(): Int =
-            name.hashCode() * 31 + owner.hashCode()
+            descriptor.hashCode()
 
-    // TODO: include visibility, return type, maybe package
     override fun toString(): String =
-            "val $name"
+            ReflectionObjectRenderer.renderProperty(descriptor)
 }
 
 class KMutableTopLevelVariableImpl<R>(
-        name: String,
-        owner: KPackageImpl
-) : KMutableTopLevelVariable<R>, KMutableVariableImpl<R>, KTopLevelVariableImpl<R>(name, owner) {
-    override val setter: Method = try {
-        owner.jClass.getMethod(setterName(name), getter.getReturnType())
-    }
-    catch (e: NoSuchMethodException) {
-        throw NoSuchPropertyException(e)
-    }
+        container: KPackageImpl,
+        computeDescriptor: () -> PropertyDescriptor
+) : KTopLevelVariableImpl<R>(container, computeDescriptor), KMutableTopLevelVariable<R>, KMutableVariableImpl<R> {
+    override val setter: Method get() = super<KTopLevelVariableImpl>.setter!!
 
     override fun set(value: R) {
         try {
@@ -73,7 +64,4 @@ class KMutableTopLevelVariableImpl<R>(
             throw IllegalPropertyAccessException(e)
         }
     }
-
-    override fun toString(): String =
-            "var $name"
 }

core/reflection.jvm/src/kotlin/reflect/jvm/internal/ReflectionFactoryImpl.java

@@ -48,21 +48,21 @@ public class ReflectionFactoryImpl extends ReflectionFactory {
 
     @Override
     public KTopLevelVariable topLevelVariable(String name, KPackage owner) {
-        return new KTopLevelVariableImpl(name, ((KPackageImpl) owner));
+        return ((KPackageImpl) owner).topLevelVariable(name);
     }
 
     @Override
     public KMutableTopLevelVariable mutableTopLevelVariable(String name, KPackage owner) {
-        return new KMutableTopLevelVariableImpl(name, (KPackageImpl) owner);
+        return ((KPackageImpl) owner).mutableTopLevelVariable(name);
     }
 
     @Override
     public KTopLevelExtensionProperty topLevelExtensionProperty(String name, KPackage owner, Class receiver) {
-        return new KTopLevelExtensionPropertyImpl(name, (KPackageImpl) owner, receiver);
+        return ((KPackageImpl) owner).topLevelExtensionProperty(name, receiver);
     }
 
     @Override
     public KMutableTopLevelExtensionProperty mutableTopLevelExtensionProperty(String name, KPackage owner, Class receiver) {
-        return new KMutableTopLevelExtensionPropertyImpl(name, (KPackageImpl) owner, receiver);
+        return ((KPackageImpl) owner).mutableTopLevelExtensionProperty(name, receiver);
     }
 }

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

@@ -16,8 +16,11 @@
 
 package kotlin.reflect.jvm.internal
 
+import org.jetbrains.kotlin.load.java.structure.reflect.classId
 import org.jetbrains.kotlin.load.java.structure.reflect.classLoader
 import org.jetbrains.kotlin.load.java.structure.reflect.createArrayType
+import org.jetbrains.kotlin.name.ClassId
+import org.jetbrains.kotlin.serialization.ProtoBuf
 import org.jetbrains.kotlin.serialization.deserialization.NameResolver
 import org.jetbrains.kotlin.serialization.jvm.JvmProtoBuf
 import org.jetbrains.kotlin.serialization.jvm.JvmProtoBuf.JvmType.PrimitiveType.*
@@ -61,13 +64,26 @@ private fun KCallableContainerImpl.findMethodBySignature(signature: JvmProtoBuf.
 }
 
 // TODO: check resulting field's type
-private fun KCallableContainerImpl.findFieldBySignature(signature: JvmProtoBuf.JvmFieldSignature, nameResolver: NameResolver): Field? {
+private fun KCallableContainerImpl.findFieldBySignature(
+        proto: ProtoBuf.Callable,
+        signature: JvmProtoBuf.JvmFieldSignature,
+        nameResolver: NameResolver
+): Field? {
     val name = nameResolver.getString(signature.getName())
+
     val owner =
-            if (signature.getIsStaticInOuter())
-                jClass.getEnclosingClass()
-                ?: throw KotlinReflectionInternalError("Inconsistent metadata for field $name in $jClass")
-            else jClass
+            when {
+                proto.hasExtension(JvmProtoBuf.implClassName) -> {
+                    val implClassName = nameResolver.getName(proto.getExtension(JvmProtoBuf.implClassName))
+                    // TODO: store fq name of impl class name in jvm_descriptors.proto
+                    val classId = ClassId(jClass.classId.getPackageFqName(), implClassName)
+                    jClass.classLoader.loadClass(classId.asSingleFqName().asString())
+                }
+                signature.getIsStaticInOuter() -> {
+                    jClass.getEnclosingClass() ?: throw KotlinReflectionInternalError("Inconsistent metadata for field $name in $jClass")
+                }
+                else -> jClass
+            }
 
     return try {
         owner.getDeclaredField(name)

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

@@ -16,7 +16,9 @@
 
 package kotlin.reflect.jvm
 
-import java.lang.reflect.*
+import java.lang.reflect.Field
+import java.lang.reflect.Method
+import java.lang.reflect.Modifier
 import kotlin.jvm.internal.Reflection
 import kotlin.reflect.*
 import kotlin.reflect.jvm.internal.*
@@ -37,7 +39,8 @@ public val KMutableProperty<*>.javaSetter: Method?
     get() = (this as? KMutablePropertyImpl<*>)?.setter
 
 
-// TODO: val KTopLevelVariable<*>.javaField: Field
+public val KTopLevelVariable<*>.javaField: Field?
+    get() = (this as KPropertyImpl<*>).field
 
 public val KTopLevelVariable<*>.javaGetter: Method
     get() = (this as KTopLevelVariableImpl<*>).getter