Introduce better typing for on[event-name] attributes from idl

see https://upsource.jetbrains.com/kotlin/review/KOTLIN-CR-2548

libraries/stdlib/js/src/org.w3c/org.w3c.dom.kt

@@ -75,62 +75,62 @@ public external open class Document : Node, GlobalEventHandlers, DocumentAndElem
     open val documentElement: Element?
     open val scrollingElement: Element?
     open val styleSheets: StyleSheetList
-    override var ongotpointercapture: ((Event) -> dynamic)?
-    override var onlostpointercapture: ((Event) -> dynamic)?
-    override var onpointerdown: ((Event) -> dynamic)?
-    override var onpointermove: ((Event) -> dynamic)?
-    override var onpointerup: ((Event) -> dynamic)?
-    override var onpointercancel: ((Event) -> dynamic)?
-    override var onpointerover: ((Event) -> dynamic)?
-    override var onpointerout: ((Event) -> dynamic)?
-    override var onpointerenter: ((Event) -> dynamic)?
-    override var onpointerleave: ((Event) -> dynamic)?
+    override var ongotpointercapture: ((PointerEvent) -> dynamic)?
+    override var onlostpointercapture: ((PointerEvent) -> dynamic)?
+    override var onpointerdown: ((PointerEvent) -> dynamic)?
+    override var onpointermove: ((PointerEvent) -> dynamic)?
+    override var onpointerup: ((PointerEvent) -> dynamic)?
+    override var onpointercancel: ((PointerEvent) -> dynamic)?
+    override var onpointerover: ((PointerEvent) -> dynamic)?
+    override var onpointerout: ((PointerEvent) -> dynamic)?
+    override var onpointerenter: ((PointerEvent) -> dynamic)?
+    override var onpointerleave: ((PointerEvent) -> dynamic)?
     override var onabort: ((Event) -> dynamic)?
-    override var onblur: ((Event) -> dynamic)?
+    override var onblur: ((FocusEvent) -> dynamic)?
     override var oncancel: ((Event) -> dynamic)?
     override var oncanplay: ((Event) -> dynamic)?
     override var oncanplaythrough: ((Event) -> dynamic)?
     override var onchange: ((Event) -> dynamic)?
-    override var onclick: ((Event) -> dynamic)?
+    override var onclick: ((MouseEvent) -> dynamic)?
     override var onclose: ((Event) -> dynamic)?
-    override var oncontextmenu: ((Event) -> dynamic)?
+    override var oncontextmenu: ((MouseEvent) -> dynamic)?
     override var oncuechange: ((Event) -> dynamic)?
-    override var ondblclick: ((Event) -> dynamic)?
-    override var ondrag: ((Event) -> dynamic)?
-    override var ondragend: ((Event) -> dynamic)?
-    override var ondragenter: ((Event) -> dynamic)?
-    override var ondragexit: ((Event) -> dynamic)?
-    override var ondragleave: ((Event) -> dynamic)?
-    override var ondragover: ((Event) -> dynamic)?
-    override var ondragstart: ((Event) -> dynamic)?
-    override var ondrop: ((Event) -> dynamic)?
+    override var ondblclick: ((MouseEvent) -> dynamic)?
+    override var ondrag: ((DragEvent) -> dynamic)?
+    override var ondragend: ((DragEvent) -> dynamic)?
+    override var ondragenter: ((DragEvent) -> dynamic)?
+    override var ondragexit: ((DragEvent) -> dynamic)?
+    override var ondragleave: ((DragEvent) -> dynamic)?
+    override var ondragover: ((DragEvent) -> dynamic)?
+    override var ondragstart: ((DragEvent) -> dynamic)?
+    override var ondrop: ((DragEvent) -> dynamic)?
     override var ondurationchange: ((Event) -> dynamic)?
     override var onemptied: ((Event) -> dynamic)?
     override var onended: ((Event) -> dynamic)?
     override var onerror: ((dynamic, String, Int, Int, Any?) -> dynamic)?
-    override var onfocus: ((Event) -> dynamic)?
-    override var oninput: ((Event) -> dynamic)?
+    override var onfocus: ((FocusEvent) -> dynamic)?
+    override var oninput: ((InputEvent) -> dynamic)?
     override var oninvalid: ((Event) -> dynamic)?
-    override var onkeydown: ((Event) -> dynamic)?
-    override var onkeypress: ((Event) -> dynamic)?
-    override var onkeyup: ((Event) -> dynamic)?
+    override var onkeydown: ((KeyboardEvent) -> dynamic)?
+    override var onkeypress: ((KeyboardEvent) -> dynamic)?
+    override var onkeyup: ((KeyboardEvent) -> dynamic)?
     override var onload: ((Event) -> dynamic)?
     override var onloadeddata: ((Event) -> dynamic)?
     override var onloadedmetadata: ((Event) -> dynamic)?
     override var onloadend: ((Event) -> dynamic)?
-    override var onloadstart: ((Event) -> dynamic)?
-    override var onmousedown: ((Event) -> dynamic)?
-    override var onmouseenter: ((Event) -> dynamic)?
-    override var onmouseleave: ((Event) -> dynamic)?
-    override var onmousemove: ((Event) -> dynamic)?
-    override var onmouseout: ((Event) -> dynamic)?
-    override var onmouseover: ((Event) -> dynamic)?
-    override var onmouseup: ((Event) -> dynamic)?
-    override var onwheel: ((Event) -> dynamic)?
+    override var onloadstart: ((ProgressEvent) -> dynamic)?
+    override var onmousedown: ((MouseEvent) -> dynamic)?
+    override var onmouseenter: ((MouseEvent) -> dynamic)?
+    override var onmouseleave: ((MouseEvent) -> dynamic)?
+    override var onmousemove: ((MouseEvent) -> dynamic)?
+    override var onmouseout: ((MouseEvent) -> dynamic)?
+    override var onmouseover: ((MouseEvent) -> dynamic)?
+    override var onmouseup: ((MouseEvent) -> dynamic)?
+    override var onwheel: ((WheelEvent) -> dynamic)?
     override var onpause: ((Event) -> dynamic)?
     override var onplay: ((Event) -> dynamic)?
     override var onplaying: ((Event) -> dynamic)?
-    override var onprogress: ((Event) -> dynamic)?
+    override var onprogress: ((ProgressEvent) -> dynamic)?
     override var onratechange: ((Event) -> dynamic)?
     override var onreset: ((Event) -> dynamic)?
     override var onresize: ((Event) -> dynamic)?
@@ -2032,7 +2032,7 @@ public external abstract class ApplicationCache : EventTarget {
     open var onerror: ((Event) -> dynamic)?
     open var onnoupdate: ((Event) -> dynamic)?
     open var ondownloading: ((Event) -> dynamic)?
-    open var onprogress: ((Event) -> dynamic)?
+    open var onprogress: ((ProgressEvent) -> dynamic)?
     open var onupdateready: ((Event) -> dynamic)?
     open var oncached: ((Event) -> dynamic)?
     open var onobsolete: ((Event) -> dynamic)?
@@ -2136,62 +2136,62 @@ public inline fun PromiseRejectionEventInit(promise: Promise<Any?>?, reason: Any
  * Exposes the JavaScript [GlobalEventHandlers](https://developer.mozilla.org/en/docs/Web/API/GlobalEventHandlers) to Kotlin
  */
 public external interface GlobalEventHandlers {
-    var ongotpointercapture: ((Event) -> dynamic)?
-    var onlostpointercapture: ((Event) -> dynamic)?
-    var onpointerdown: ((Event) -> dynamic)?
-    var onpointermove: ((Event) -> dynamic)?
-    var onpointerup: ((Event) -> dynamic)?
-    var onpointercancel: ((Event) -> dynamic)?
-    var onpointerover: ((Event) -> dynamic)?
-    var onpointerout: ((Event) -> dynamic)?
-    var onpointerenter: ((Event) -> dynamic)?
-    var onpointerleave: ((Event) -> dynamic)?
+    var ongotpointercapture: ((PointerEvent) -> dynamic)?
+    var onlostpointercapture: ((PointerEvent) -> dynamic)?
+    var onpointerdown: ((PointerEvent) -> dynamic)?
+    var onpointermove: ((PointerEvent) -> dynamic)?
+    var onpointerup: ((PointerEvent) -> dynamic)?
+    var onpointercancel: ((PointerEvent) -> dynamic)?
+    var onpointerover: ((PointerEvent) -> dynamic)?
+    var onpointerout: ((PointerEvent) -> dynamic)?
+    var onpointerenter: ((PointerEvent) -> dynamic)?
+    var onpointerleave: ((PointerEvent) -> dynamic)?
     var onabort: ((Event) -> dynamic)?
-    var onblur: ((Event) -> dynamic)?
+    var onblur: ((FocusEvent) -> dynamic)?
     var oncancel: ((Event) -> dynamic)?
     var oncanplay: ((Event) -> dynamic)?
     var oncanplaythrough: ((Event) -> dynamic)?
     var onchange: ((Event) -> dynamic)?
-    var onclick: ((Event) -> dynamic)?
+    var onclick: ((MouseEvent) -> dynamic)?
     var onclose: ((Event) -> dynamic)?
-    var oncontextmenu: ((Event) -> dynamic)?
+    var oncontextmenu: ((MouseEvent) -> dynamic)?
     var oncuechange: ((Event) -> dynamic)?
-    var ondblclick: ((Event) -> dynamic)?
-    var ondrag: ((Event) -> dynamic)?
-    var ondragend: ((Event) -> dynamic)?
-    var ondragenter: ((Event) -> dynamic)?
-    var ondragexit: ((Event) -> dynamic)?
-    var ondragleave: ((Event) -> dynamic)?
-    var ondragover: ((Event) -> dynamic)?
-    var ondragstart: ((Event) -> dynamic)?
-    var ondrop: ((Event) -> dynamic)?
+    var ondblclick: ((MouseEvent) -> dynamic)?
+    var ondrag: ((DragEvent) -> dynamic)?
+    var ondragend: ((DragEvent) -> dynamic)?
+    var ondragenter: ((DragEvent) -> dynamic)?
+    var ondragexit: ((DragEvent) -> dynamic)?
+    var ondragleave: ((DragEvent) -> dynamic)?
+    var ondragover: ((DragEvent) -> dynamic)?
+    var ondragstart: ((DragEvent) -> dynamic)?
+    var ondrop: ((DragEvent) -> dynamic)?
     var ondurationchange: ((Event) -> dynamic)?
     var onemptied: ((Event) -> dynamic)?
     var onended: ((Event) -> dynamic)?
     var onerror: ((dynamic, String, Int, Int, Any?) -> dynamic)?
-    var onfocus: ((Event) -> dynamic)?
-    var oninput: ((Event) -> dynamic)?
+    var onfocus: ((FocusEvent) -> dynamic)?
+    var oninput: ((InputEvent) -> dynamic)?
     var oninvalid: ((Event) -> dynamic)?
-    var onkeydown: ((Event) -> dynamic)?
-    var onkeypress: ((Event) -> dynamic)?
-    var onkeyup: ((Event) -> dynamic)?
+    var onkeydown: ((KeyboardEvent) -> dynamic)?
+    var onkeypress: ((KeyboardEvent) -> dynamic)?
+    var onkeyup: ((KeyboardEvent) -> dynamic)?
     var onload: ((Event) -> dynamic)?
     var onloadeddata: ((Event) -> dynamic)?
     var onloadedmetadata: ((Event) -> dynamic)?
     var onloadend: ((Event) -> dynamic)?
-    var onloadstart: ((Event) -> dynamic)?
-    var onmousedown: ((Event) -> dynamic)?
-    var onmouseenter: ((Event) -> dynamic)?
-    var onmouseleave: ((Event) -> dynamic)?
-    var onmousemove: ((Event) -> dynamic)?
-    var onmouseout: ((Event) -> dynamic)?
-    var onmouseover: ((Event) -> dynamic)?
-    var onmouseup: ((Event) -> dynamic)?
-    var onwheel: ((Event) -> dynamic)?
+    var onloadstart: ((ProgressEvent) -> dynamic)?
+    var onmousedown: ((MouseEvent) -> dynamic)?
+    var onmouseenter: ((MouseEvent) -> dynamic)?
+    var onmouseleave: ((MouseEvent) -> dynamic)?
+    var onmousemove: ((MouseEvent) -> dynamic)?
+    var onmouseout: ((MouseEvent) -> dynamic)?
+    var onmouseover: ((MouseEvent) -> dynamic)?
+    var onmouseup: ((MouseEvent) -> dynamic)?
+    var onwheel: ((WheelEvent) -> dynamic)?
     var onpause: ((Event) -> dynamic)?
     var onplay: ((Event) -> dynamic)?
     var onplaying: ((Event) -> dynamic)?
-    var onprogress: ((Event) -> dynamic)?
+    var onprogress: ((ProgressEvent) -> dynamic)?
     var onratechange: ((Event) -> dynamic)?
     var onreset: ((Event) -> dynamic)?
     var onresize: ((Event) -> dynamic)?
@@ -2215,18 +2215,18 @@ public external interface GlobalEventHandlers {
 public external interface WindowEventHandlers {
     var onafterprint: ((Event) -> dynamic)?
     var onbeforeprint: ((Event) -> dynamic)?
-    var onbeforeunload: ((Event) -> String?)?
-    var onhashchange: ((Event) -> dynamic)?
+    var onbeforeunload: ((BeforeUnloadEvent) -> String?)?
+    var onhashchange: ((HashChangeEvent) -> dynamic)?
     var onlanguagechange: ((Event) -> dynamic)?
-    var onmessage: ((Event) -> dynamic)?
+    var onmessage: ((MessageEvent) -> dynamic)?
     var onoffline: ((Event) -> dynamic)?
     var ononline: ((Event) -> dynamic)?
-    var onpagehide: ((Event) -> dynamic)?
-    var onpageshow: ((Event) -> dynamic)?
-    var onpopstate: ((Event) -> dynamic)?
+    var onpagehide: ((PageTransitionEvent) -> dynamic)?
+    var onpageshow: ((PageTransitionEvent) -> dynamic)?
+    var onpopstate: ((PopStateEvent) -> dynamic)?
     var onrejectionhandled: ((Event) -> dynamic)?
-    var onstorage: ((Event) -> dynamic)?
-    var onunhandledrejection: ((Event) -> dynamic)?
+    var onstorage: ((StorageEvent) -> dynamic)?
+    var onunhandledrejection: ((PromiseRejectionEvent) -> dynamic)?
     var onunload: ((Event) -> dynamic)?
 }
 
@@ -2454,7 +2454,7 @@ public external open class EventSource(url: String, eventSourceInitDict: EventSo
     open val withCredentials: Boolean
     open val readyState: Short
     var onopen: ((Event) -> dynamic)?
-    var onmessage: ((Event) -> dynamic)?
+    var onmessage: ((MessageEvent) -> dynamic)?
     var onerror: ((Event) -> dynamic)?
     fun close(): Unit
 
@@ -2492,7 +2492,7 @@ public external open class WebSocket(url: String, protocols: dynamic = definedEx
     var onclose: ((Event) -> dynamic)?
     open val extensions: String
     open val protocol: String
-    var onmessage: ((Event) -> dynamic)?
+    var onmessage: ((MessageEvent) -> dynamic)?
     var binaryType: BinaryType
     fun close(code: Short = definedExternally, reason: String = definedExternally): Unit
     fun send(data: String): Unit
@@ -2555,7 +2555,7 @@ public external open class MessageChannel {
  * Exposes the JavaScript [MessagePort](https://developer.mozilla.org/en/docs/Web/API/MessagePort) to Kotlin
  */
 public external abstract class MessagePort : EventTarget, UnionMessagePortOrWindow, UnionMessagePortOrServiceWorker, UnionClientOrMessagePortOrServiceWorker {
-    open var onmessage: ((Event) -> dynamic)?
+    open var onmessage: ((MessageEvent) -> dynamic)?
     fun postMessage(message: Any?, transfer: Array<dynamic> = definedExternally): Unit
     fun start(): Unit
     fun close(): Unit
@@ -2566,7 +2566,7 @@ public external abstract class MessagePort : EventTarget, UnionMessagePortOrWind
  */
 public external open class BroadcastChannel(name: String) : EventTarget {
     open val name: String
-    var onmessage: ((Event) -> dynamic)?
+    var onmessage: ((MessageEvent) -> dynamic)?
     fun postMessage(message: Any?): Unit
     fun close(): Unit
 }
@@ -2583,7 +2583,7 @@ public external abstract class WorkerGlobalScope : EventTarget, WindowOrWorkerGl
     open var onoffline: ((Event) -> dynamic)?
     open var ononline: ((Event) -> dynamic)?
     open var onrejectionhandled: ((Event) -> dynamic)?
-    open var onunhandledrejection: ((Event) -> dynamic)?
+    open var onunhandledrejection: ((PromiseRejectionEvent) -> dynamic)?
     fun importScripts(vararg urls: String): Unit
 }
 
@@ -2591,7 +2591,7 @@ public external abstract class WorkerGlobalScope : EventTarget, WindowOrWorkerGl
  * Exposes the JavaScript [DedicatedWorkerGlobalScope](https://developer.mozilla.org/en/docs/Web/API/DedicatedWorkerGlobalScope) to Kotlin
  */
 public external abstract class DedicatedWorkerGlobalScope : WorkerGlobalScope {
-    open var onmessage: ((Event) -> dynamic)?
+    open var onmessage: ((MessageEvent) -> dynamic)?
     fun postMessage(message: Any?, transfer: Array<dynamic> = definedExternally): Unit
     fun close(): Unit
 }
@@ -2617,7 +2617,7 @@ public external interface AbstractWorker {
  * Exposes the JavaScript [Worker](https://developer.mozilla.org/en/docs/Web/API/Worker) to Kotlin
  */
 public external open class Worker(scriptURL: String, options: WorkerOptions = definedExternally) : EventTarget, AbstractWorker {
-    var onmessage: ((Event) -> dynamic)?
+    var onmessage: ((MessageEvent) -> dynamic)?
     override var onerror: ((Event) -> dynamic)?
     fun terminate(): Unit
     fun postMessage(message: Any?, transfer: Array<dynamic> = definedExternally): Unit

libraries/stdlib/js/src/org.w3c/org.w3c.files.kt

@@ -90,8 +90,8 @@ public external open class FileReader : EventTarget {
     open val readyState: Short
     open val result: dynamic
     open val error: dynamic
-    var onloadstart: ((Event) -> dynamic)?
-    var onprogress: ((Event) -> dynamic)?
+    var onloadstart: ((ProgressEvent) -> dynamic)?
+    var onprogress: ((ProgressEvent) -> dynamic)?
     var onload: ((Event) -> dynamic)?
     var onabort: ((Event) -> dynamic)?
     var onerror: ((Event) -> dynamic)?

libraries/stdlib/js/src/org.w3c/org.w3c.notifications.kt

@@ -28,7 +28,7 @@ import org.w3c.xhr.*
  * Exposes the JavaScript [Notification](https://developer.mozilla.org/en/docs/Web/API/Notification) to Kotlin
  */
 public external open class Notification(title: String, options: NotificationOptions = definedExternally) : EventTarget {
-    var onclick: ((Event) -> dynamic)?
+    var onclick: ((MouseEvent) -> dynamic)?
     var onerror: ((Event) -> dynamic)?
     open val title: String
     open val dir: NotificationDirection

libraries/stdlib/js/src/org.w3c/org.w3c.workers.kt

@@ -49,12 +49,12 @@ public external abstract class ServiceWorkerGlobalScope : WorkerGlobalScope {
     open val registration: ServiceWorkerRegistration
     open var oninstall: ((Event) -> dynamic)?
     open var onactivate: ((Event) -> dynamic)?
-    open var onfetch: ((Event) -> dynamic)?
+    open var onfetch: ((FetchEvent) -> dynamic)?
     open var onforeignfetch: ((Event) -> dynamic)?
-    open var onmessage: ((Event) -> dynamic)?
+    open var onmessage: ((MessageEvent) -> dynamic)?
     open var onfunctionalevent: ((Event) -> dynamic)?
-    open var onnotificationclick: ((Event) -> dynamic)?
-    open var onnotificationclose: ((Event) -> dynamic)?
+    open var onnotificationclick: ((NotificationEvent) -> dynamic)?
+    open var onnotificationclose: ((NotificationEvent) -> dynamic)?
     fun skipWaiting(): Promise<Unit>
 }
 
@@ -75,7 +75,7 @@ public external abstract class ServiceWorkerContainer : EventTarget {
     open val controller: ServiceWorker?
     open val ready: Promise<ServiceWorkerRegistration>
     open var oncontrollerchange: ((Event) -> dynamic)?
-    open var onmessage: ((Event) -> dynamic)?
+    open var onmessage: ((MessageEvent) -> dynamic)?
     fun register(scriptURL: String, options: RegistrationOptions = definedExternally): Promise<ServiceWorkerRegistration>
     fun getRegistration(clientURL: String = definedExternally): Promise<Any?>
     fun getRegistrations(): Promise<dynamic>

libraries/stdlib/js/src/org.w3c/org.w3c.xhr.kt

@@ -28,8 +28,8 @@ import org.w3c.workers.*
  * Exposes the JavaScript [XMLHttpRequestEventTarget](https://developer.mozilla.org/en/docs/Web/API/XMLHttpRequestEventTarget) to Kotlin
  */
 public external abstract class XMLHttpRequestEventTarget : EventTarget {
-    open var onloadstart: ((Event) -> dynamic)?
-    open var onprogress: ((Event) -> dynamic)?
+    open var onloadstart: ((ProgressEvent) -> dynamic)?
+    open var onprogress: ((ProgressEvent) -> dynamic)?
     open var onabort: ((Event) -> dynamic)?
     open var onerror: ((Event) -> dynamic)?
     open var onload: ((Event) -> dynamic)?

libraries/tools/idl2k/src/main/kotlin/config.kt

@@ -91,4 +91,71 @@ val kotlinBuiltinInterfaces = mapOf(
                 primaryConstructor = null,
                 secondaryConstructors = emptyList()
                 )
-)
+)
+
+val specifyEventMapper = mapOf<String, String>(
+        "onbeforeunload" to "BeforeUnloadEvent",
+
+        "ondrag" to "DragEvent",
+        "ondragend" to "DragEvent",
+        "ondragenter" to "DragEvent",
+        "ondragexit" to "DragEvent",
+        "ondragleave" to "DragEvent",
+        "ondragover" to "DragEvent",
+        "ondragstart" to "DragEvent",
+        "ondrop" to "DragEvent",
+
+        "onfetch" to "FetchEvent",
+
+        "onblur" to "FocusEvent",
+        "onfocus" to "FocusEvent",
+
+        "onhashchange" to "HashChangeEvent",
+
+        "oninput" to "InputEvent",
+
+        "onkeydown" to "KeyboardEvent",
+        "onkeypress" to "KeyboardEvent",
+        "onkeyup" to "KeyboardEvent",
+
+        "onmessage" to "MessageEvent",
+
+        "onclick" to "MouseEvent",
+        "oncontextmenu" to "MouseEvent",
+        "ondblclick" to "MouseEvent",
+        "onmousedown" to "MouseEvent",
+        "onmouseenter" to "MouseEvent",
+        "onmouseleave" to "MouseEvent",
+        "onmousemove" to "MouseEvent",
+        "onmouseout" to "MouseEvent",
+        "onmouseover" to "MouseEvent",
+        "onmouseup" to "MouseEvent",
+
+        "onnotificationclick" to "NotificationEvent",
+        "onnotificationclose" to "NotificationEvent",
+
+        "onpagehide" to "PageTransitionEvent",
+        "onpageshow" to "PageTransitionEvent",
+
+        "ongotpointercapture" to "PointerEvent",
+        "onlostpointercapture" to "PointerEvent",
+        "onpointercancel" to "PointerEvent",
+        "onpointerdown" to "PointerEvent",
+        "onpointerenter" to "PointerEvent",
+        "onpointerleave" to "PointerEvent",
+        "onpointermove" to "PointerEvent",
+        "onpointerout" to "PointerEvent",
+        "onpointerover" to "PointerEvent",
+        "onpointerup" to "PointerEvent",
+
+        "onpopstate" to "PopStateEvent",
+
+        "onloadstart" to "ProgressEvent",
+        "onprogress" to "ProgressEvent",
+
+        "onunhandledrejection" to "PromiseRejectionEvent",
+
+        "onstorage" to "StorageEvent",
+
+        "onwheel" to "WheelEvent"
+)

libraries/tools/idl2k/src/main/kotlin/gen.kt

@@ -86,26 +86,26 @@ fun generateFunctions(repository: Repository, function: Operation): List<Generat
     return listOf(realFunction, getterOrSetterFunction, functionWithCallbackOrNull).filterNotNull()
 }
 
-fun generateAttribute(putNoImpl: Boolean, repository: Repository, attribute: Attribute, nullableAttributes: Boolean): GenerateAttribute =
-        GenerateAttribute(attribute.name,
-                type = mapType(repository, attribute.type).let { if (nullableAttributes) it.toNullable() else it },
-                initializer =
-                    if (putNoImpl && !attribute.static) {
-                        mapLiteral(attribute.defaultValue, mapType(repository, attribute.type), repository.enums)
-                    }
-                    else if (attribute.defaultValue != null) {
-                        "definedExternally"
-                    }
-                    else {
-                        null
-                    },
-                getterSetterNoImpl = putNoImpl,
-                kind = if (attribute.readOnly) AttributeKind.VAL else AttributeKind.VAR,
-                override = false,
-                vararg = attribute.vararg,
-                static = attribute.static,
-                required = attribute.required
-        )
+fun generateAttribute(putNoImpl: Boolean, repository: Repository, attribute: Attribute, nullableAttributes: Boolean): GenerateAttribute {
+    val mappedType = mapType(repository, attribute.type).let { if (nullableAttributes) it.toNullable() else it }
+    return GenerateAttribute(attribute.name,
+                             type = generalizeType(attribute.name, mappedType),
+                             initializer =
+                             if (putNoImpl && !attribute.static) {
+                                 mapLiteral(attribute.defaultValue, mapType(repository, attribute.type), repository.enums)
+                             } else if (attribute.defaultValue != null) {
+                                 "definedExternally"
+                             } else {
+                                 null
+                             },
+                             getterSetterNoImpl = putNoImpl,
+                             kind = if (attribute.readOnly) AttributeKind.VAL else AttributeKind.VAR,
+                             override = false,
+                             vararg = attribute.vararg,
+                             static = attribute.static,
+                             required = attribute.required
+    )
+}
 
 private fun InterfaceDefinition.superTypes(repository: Repository) = superTypes.map { repository.interfaces[it] }.filterNotNull()
 private fun resolveDefinitionKind(repository: Repository, iface: InterfaceDefinition, constructors: List<ExtendedAttribute> = iface.findConstructors()): GenerateDefinitionKind =
@@ -259,6 +259,25 @@ private fun mapLiteral(literal: String?, expectedType: Type = DynamicType, enums
         }
     }
 
+
+private fun specifyType(name: String, type: Type): Type {
+    if ((type is SimpleType) && (type.type == "Event")) {
+        specifyEventMapper[name]?.let {
+            return type.copy(type = it)
+        }
+    }
+
+    return type
+}
+
+private fun generalizeType(name: String, type: Type): Type {
+    if ((type is FunctionType) && (type.parameterTypes.size == 1)) {
+        val paramAttribute = type.parameterTypes[0]
+        return type.copy(parameterTypes = listOf(paramAttribute.copy(type = specifyType(name, paramAttribute.type))))
+    }
+    return type
+}
+
 fun implementInterfaces(declarations: List<GenerateTraitOrClass>) {
     val unimplementedMemberMap = getUnimplementedMembers(declarations)
     val nonAbstractDeclarations = declarations.filter { it.kind == GenerateDefinitionKind.CLASS }
@@ -266,7 +285,7 @@ fun implementInterfaces(declarations: List<GenerateTraitOrClass>) {
         val unimplementedMembers = unimplementedMemberMap[declaration.name] ?: continue
 
         for (attribute in unimplementedMembers.attributes) {
-            declaration.memberAttributes += attribute.copy(override = true)
+            declaration.memberAttributes += attribute.copy(override = true, type = generalizeType(attribute.name, attribute.type))
         }
         for (function in unimplementedMembers.functions) {
             declaration.memberFunctions += function.copy(override = true)

libraries/tools/idl2k/src/main/kotlin/typeMappings.kt

@@ -19,42 +19,49 @@ package org.jetbrains.idl2k
 import java.util.*
 
 private val typeMapper = mapOf(
-        "unsignedlong" to SimpleType("Int", false),
-        "unsignedlonglong" to SimpleType("Int", false),
-        "longlong" to SimpleType("Int", false),
-        "unsignedshort" to SimpleType("Short", false),
-        "unsignedbyte" to SimpleType("Byte", false),
-        "octet" to SimpleType("Byte", false),
-        "void" to UnitType,
-        "boolean" to SimpleType("Boolean", false),
-        "byte" to SimpleType("Byte", false),
-        "short" to SimpleType("Short", false),
-        "long" to SimpleType("Int", false),
-        "float" to SimpleType("Float", false),
-        "double" to SimpleType("Double", false),
-        "any" to AnyType(true),
-        "DOMTimeStamp" to SimpleType("Number", false),
-        "object" to DynamicType, // TODO map to Any?
-        "WindowProxy" to SimpleType("Window", false),
-        "USVString" to SimpleType("String", false),
-        "DOMString" to SimpleType("String", false),
-        "ByteString" to SimpleType("String", false),
-        "DOMError" to DynamicType,
-        "Elements" to DynamicType,
-        "Date" to SimpleType("Date", false),
-        "" to DynamicType
+    "unsignedlong" to SimpleType("Int", false),
+    "unsignedlonglong" to SimpleType("Int", false),
+    "longlong" to SimpleType("Int", false),
+    "unsignedshort" to SimpleType("Short", false),
+    "unsignedbyte" to SimpleType("Byte", false),
+    "octet" to SimpleType("Byte", false),
+    "void" to UnitType,
+    "boolean" to SimpleType("Boolean", false),
+    "byte" to SimpleType("Byte", false),
+    "short" to SimpleType("Short", false),
+    "long" to SimpleType("Int", false),
+    "float" to SimpleType("Float", false),
+    "double" to SimpleType("Double", false),
+    "any" to AnyType(true),
+    "DOMTimeStamp" to SimpleType("Number", false),
+    "object" to DynamicType, // TODO map to Any?
+    "WindowProxy" to SimpleType("Window", false),
+    "USVString" to SimpleType("String", false),
+    "DOMString" to SimpleType("String", false),
+    "ByteString" to SimpleType("String", false),
+    "DOMError" to DynamicType,
+    "Elements" to DynamicType,
+    "Date" to SimpleType("Date", false),
+    "" to DynamicType
 )
 
 
-fun GenerateTraitOrClass.allSuperTypes(all: Map<String, GenerateTraitOrClass>) = LinkedHashSet<GenerateTraitOrClass>().let { result -> allSuperTypesImpl(listOf(this), all, result); result.toList() }
+fun GenerateTraitOrClass.allSuperTypes(all: Map<String, GenerateTraitOrClass>) =
+    LinkedHashSet<GenerateTraitOrClass>().let { result -> allSuperTypesImpl(listOf(this), all, result); result.toList() }
 
-tailrec fun allSuperTypesImpl(roots: List<GenerateTraitOrClass>, all: Map<String, GenerateTraitOrClass>, result: MutableSet<GenerateTraitOrClass>) {
+tailrec fun allSuperTypesImpl(
+    roots: List<GenerateTraitOrClass>,
+    all: Map<String, GenerateTraitOrClass>,
+    result: MutableSet<GenerateTraitOrClass>
+) {
     if (roots.isNotEmpty()) {
-        allSuperTypesImpl(roots.flatMap { it.superTypes }.map { all[it] ?: all[it.substringBefore("<")] }.filterNotNull().filter { result.add(it) }, all, result)
+        allSuperTypesImpl(roots.flatMap { it.superTypes }.map {
+            all[it] ?: all[it.substringBefore("<")]
+        }.filterNotNull().filter { result.add(it) }, all, result)
     }
 }
 
-fun standardTypes() = typeMapper.values.map {it.dropNullable()}.toSet()
+fun standardTypes() = typeMapper.values.map { it.dropNullable() }.toSet()
 fun Type.dynamicIfUnknownType(allTypes: Set<String>, standardTypes: Set<Type> = standardTypes()): Type = when {
     this is DynamicType || this is UnitType -> this
 
@@ -62,7 +69,16 @@ fun Type.dynamicIfUnknownType(allTypes: Set<String>, standardTypes: Set<Type> =
     this.dropNullable() in standardTypes -> this
     this is ArrayType -> copy(memberType = this.memberType.dynamicIfUnknownType(allTypes, standardTypes))
     this is UnionType -> if (this.name !in allTypes) DynamicType else this
-    this is FunctionType -> copy(returnType = returnType.dynamicIfUnknownType(allTypes, standardTypes), parameterTypes = parameterTypes.map { it.copy(type = it.type.dynamicIfUnknownType(allTypes, standardTypes)) })
+    this is FunctionType -> copy(
+        returnType = returnType.dynamicIfUnknownType(allTypes, standardTypes),
+        parameterTypes = parameterTypes.map {
+            it.copy(
+                type = it.type.dynamicIfUnknownType(
+                    allTypes,
+                    standardTypes
+                )
+            )
+        })
     this is PromiseType ->
         copy(valueType = valueType.dynamicIfUnknownType(allTypes, standardTypes))
 
@@ -84,11 +100,15 @@ internal fun mapType(repository: Repository, type: Type): Type = when (type) {
     }
     is PromiseType -> type.copy(valueType = mapType(repository, type.valueType))
     is ArrayType -> type.copy(memberType = mapType(repository, type.memberType))
-    is UnionType -> UnionType(type.namespace, type.memberTypes.map { mt -> mapType(repository, mt) }, type.nullable).toSingleTypeIfPossible()
+    is UnionType -> UnionType(
+        type.namespace,
+        type.memberTypes.map { mt -> mapType(repository, mt) },
+        type.nullable
+    ).toSingleTypeIfPossible()
     is FunctionType -> type.copy(
-            // TODO: Remove takeWhile { !vararg } when we have varargs supported. See KT-3115
-            returnType = mapType(repository, type.returnType).dynamicIfAnyType(),
-            parameterTypes = type.parameterTypes.takeWhile { !it.vararg }.map { it.copy(type = mapType(repository, it.type)) }
+        // TODO: Remove takeWhile { !vararg } when we have varargs supported. See KT-3115
+        returnType = mapType(repository, type.returnType).dynamicIfAnyType(),
+        parameterTypes = type.parameterTypes.takeWhile { !it.vararg }.map { it.copy(type = mapType(repository, it.type)) }
     )
 
     is AnyType,
@@ -100,30 +120,39 @@ private fun mapTypedef(repository: Repository, type: SimpleType): Type {
     val typedef = repository.typeDefs[type.type]!!
 
     return when {
-        typedef.types is UnionType && typedef.types.memberTypes.size == 1 -> mapType(repository, typedef.types.memberTypes.single().withNullability(type.nullable))
+        typedef.types is UnionType && typedef.types.memberTypes.size == 1 -> mapType(
+            repository,
+            typedef.types.memberTypes.single().withNullability(type.nullable)
+        )
         typedef.types is UnionType -> SimpleType(typedef.name, type.nullable)
         else -> mapType(repository, typedef.types.withNullability(type.nullable))
     }
 }
 
-private fun GenerateFunction?.allTypes() = if (this != null) sequenceOf(returnType) + arguments.asSequence().map { it.type } else emptySequence()
+private fun GenerateFunction?.allTypes() =
+    if (this != null) sequenceOf(returnType) + arguments.asSequence().map { it.type } else emptySequence()
 
 internal fun collectUnionTypes(allTypes: Map<String, GenerateTraitOrClass>) =
-        allTypes.values.asSequence()
-                .flatMap {
-                    it.secondaryConstructors.asSequence().flatMap { it.constructor.allTypes() } +
+    allTypes.values.asSequence()
+        .flatMap {
+            it.secondaryConstructors.asSequence().flatMap { it.constructor.allTypes() } +
                     sequenceOf(it.primaryConstructor).filterNotNull().flatMap { it.constructor.allTypes() } +
-                            it.memberAttributes.asSequence().map { it.type } +
-                            it.memberFunctions.asSequence().flatMap { it.allTypes() }
-                }
-                .filterIsInstance<UnionType>()
-                .map { it.dropNullable() }
-                .filter { it.memberTypes.all { unionMember -> unionMember is SimpleType && unionMember.type in allTypes } }
-                .distinct()
-                .map { it.copy(namespace = guessPackage(it.memberTypes.filterIsInstance<SimpleType>().map { it.type }, allTypes), types = it.memberTypes) }
+                    it.memberAttributes.asSequence().map { it.type } +
+                    it.memberFunctions.asSequence().flatMap { it.allTypes() }
+        }
+        .filterIsInstance<UnionType>()
+        .map { it.dropNullable() }
+        .filter { it.memberTypes.all { unionMember -> unionMember is SimpleType && unionMember.type in allTypes } }
+        .distinct()
+        .map {
+            it.copy(
+                namespace = guessPackage(it.memberTypes.filterIsInstance<SimpleType>().map { it.type }, allTypes),
+                types = it.memberTypes
+            )
+        }
 
-private fun guessPackage(types : List<String>, allTypes: Map<String, GenerateTraitOrClass>) =
-        types.map { allTypes[it] }
+private fun guessPackage(types: List<String>, allTypes: Map<String, GenerateTraitOrClass>) =
+    types.map { allTypes[it] }
         .map { it?.namespace }
         .filterNotNull()
         .filter { it.isNotEmpty() }