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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 01:47:29 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 01:47:29 +0000
commit0ebf5bdf043a27fd3dfb7f92e0cb63d88954c44d (patch)
treea31f07c9bcca9d56ce61e9a1ffd30ef350d513aa /dom/bindings/ObservableArrayProxyHandler.cpp
parentInitial commit. (diff)
downloadfirefox-esr-upstream/115.8.0esr.tar.xz
firefox-esr-upstream/115.8.0esr.zip
Adding upstream version 115.8.0esr.upstream/115.8.0esr
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'dom/bindings/ObservableArrayProxyHandler.cpp')
-rw-r--r--dom/bindings/ObservableArrayProxyHandler.cpp372
1 files changed, 372 insertions, 0 deletions
diff --git a/dom/bindings/ObservableArrayProxyHandler.cpp b/dom/bindings/ObservableArrayProxyHandler.cpp
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+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/dom/ObservableArrayProxyHandler.h"
+
+#include "jsapi.h"
+#include "js/friend/ErrorMessages.h"
+#include "js/Conversions.h"
+#include "js/Object.h"
+#include "mozilla/dom/JSSlots.h"
+#include "mozilla/dom/ProxyHandlerUtils.h"
+#include "mozilla/dom/ToJSValue.h"
+#include "mozilla/ErrorResult.h"
+#include "nsDebug.h"
+#include "nsJSUtils.h"
+
+namespace mozilla::dom {
+
+const char ObservableArrayProxyHandler::family = 0;
+
+bool ObservableArrayProxyHandler::defineProperty(
+ JSContext* aCx, JS::Handle<JSObject*> aProxy,
+ JS::Handle<JS::PropertyKey> aId, JS::Handle<JS::PropertyDescriptor> aDesc,
+ JS::ObjectOpResult& aResult) const {
+ if (aId.get() == s_length_id) {
+ if (aDesc.isAccessorDescriptor()) {
+ return aResult.failNotDataDescriptor();
+ }
+ if (aDesc.hasConfigurable() && aDesc.configurable()) {
+ return aResult.failInvalidDescriptor();
+ }
+ if (aDesc.hasEnumerable() && aDesc.enumerable()) {
+ return aResult.failInvalidDescriptor();
+ }
+ if (aDesc.hasWritable() && !aDesc.writable()) {
+ return aResult.failInvalidDescriptor();
+ }
+ if (aDesc.hasValue()) {
+ JS::Rooted<JSObject*> backingListObj(aCx);
+ if (!GetBackingListObject(aCx, aProxy, &backingListObj)) {
+ return false;
+ }
+
+ return SetLength(aCx, aProxy, backingListObj, aDesc.value(), aResult);
+ }
+ return aResult.succeed();
+ }
+ uint32_t index = GetArrayIndexFromId(aId);
+ if (IsArrayIndex(index)) {
+ if (aDesc.isAccessorDescriptor()) {
+ return aResult.failNotDataDescriptor();
+ }
+ if (aDesc.hasConfigurable() && !aDesc.configurable()) {
+ return aResult.failInvalidDescriptor();
+ }
+ if (aDesc.hasEnumerable() && !aDesc.enumerable()) {
+ return aResult.failInvalidDescriptor();
+ }
+ if (aDesc.hasWritable() && !aDesc.writable()) {
+ return aResult.failInvalidDescriptor();
+ }
+ if (aDesc.hasValue()) {
+ JS::Rooted<JSObject*> backingListObj(aCx);
+ if (!GetBackingListObject(aCx, aProxy, &backingListObj)) {
+ return false;
+ }
+
+ return SetIndexedValue(aCx, aProxy, backingListObj, index, aDesc.value(),
+ aResult);
+ }
+ return aResult.succeed();
+ }
+
+ return ForwardingProxyHandler::defineProperty(aCx, aProxy, aId, aDesc,
+ aResult);
+}
+
+bool ObservableArrayProxyHandler::delete_(JSContext* aCx,
+ JS::Handle<JSObject*> aProxy,
+ JS::Handle<JS::PropertyKey> aId,
+ JS::ObjectOpResult& aResult) const {
+ if (aId.get() == s_length_id) {
+ return aResult.failCantDelete();
+ }
+ uint32_t index = GetArrayIndexFromId(aId);
+ if (IsArrayIndex(index)) {
+ JS::Rooted<JSObject*> backingListObj(aCx);
+ if (!GetBackingListObject(aCx, aProxy, &backingListObj)) {
+ return false;
+ }
+
+ uint32_t oldLen = 0;
+ if (!JS::GetArrayLength(aCx, backingListObj, &oldLen)) {
+ return false;
+ }
+
+ // We do not follow the spec (step 3.3 in
+ // https://webidl.spec.whatwg.org/#es-observable-array-deleteProperty)
+ // is because `oldLen - 1` could be `-1` if the backing list is empty, but
+ // `oldLen` is `uint32_t` in practice. See also
+ // https://github.com/whatwg/webidl/issues/1049.
+ if (oldLen != index + 1) {
+ return aResult.failBadIndex();
+ }
+
+ JS::Rooted<JS::Value> value(aCx);
+ if (!JS_GetElement(aCx, backingListObj, index, &value)) {
+ return false;
+ }
+
+ if (!OnDeleteItem(aCx, aProxy, value, index)) {
+ return false;
+ }
+
+ if (!JS::SetArrayLength(aCx, backingListObj, index)) {
+ return false;
+ }
+
+ return aResult.succeed();
+ }
+ return ForwardingProxyHandler::delete_(aCx, aProxy, aId, aResult);
+}
+
+bool ObservableArrayProxyHandler::get(JSContext* aCx,
+ JS::Handle<JSObject*> aProxy,
+ JS::Handle<JS::Value> aReceiver,
+ JS::Handle<JS::PropertyKey> aId,
+ JS::MutableHandle<JS::Value> aVp) const {
+ JS::Rooted<JSObject*> backingListObj(aCx);
+ if (!GetBackingListObject(aCx, aProxy, &backingListObj)) {
+ return false;
+ }
+
+ uint32_t length = 0;
+ if (!JS::GetArrayLength(aCx, backingListObj, &length)) {
+ return false;
+ }
+
+ if (aId.get() == s_length_id) {
+ return ToJSValue(aCx, length, aVp);
+ }
+ uint32_t index = GetArrayIndexFromId(aId);
+ if (IsArrayIndex(index)) {
+ if (index >= length) {
+ aVp.setUndefined();
+ return true;
+ }
+ return JS_GetElement(aCx, backingListObj, index, aVp);
+ }
+ return ForwardingProxyHandler::get(aCx, aProxy, aReceiver, aId, aVp);
+}
+
+bool ObservableArrayProxyHandler::getOwnPropertyDescriptor(
+ JSContext* aCx, JS::Handle<JSObject*> aProxy,
+ JS::Handle<JS::PropertyKey> aId,
+ JS::MutableHandle<Maybe<JS::PropertyDescriptor>> aDesc) const {
+ JS::Rooted<JSObject*> backingListObj(aCx);
+ if (!GetBackingListObject(aCx, aProxy, &backingListObj)) {
+ return false;
+ }
+
+ uint32_t length = 0;
+ if (!JS::GetArrayLength(aCx, backingListObj, &length)) {
+ return false;
+ }
+
+ if (aId.get() == s_length_id) {
+ JS::Rooted<JS::Value> value(aCx, JS::NumberValue(length));
+ aDesc.set(Some(JS::PropertyDescriptor::Data(
+ value, {JS::PropertyAttribute::Writable})));
+ return true;
+ }
+ uint32_t index = GetArrayIndexFromId(aId);
+ if (IsArrayIndex(index)) {
+ if (index >= length) {
+ return true;
+ }
+
+ JS::Rooted<JS::Value> value(aCx);
+ if (!JS_GetElement(aCx, backingListObj, index, &value)) {
+ return false;
+ }
+
+ aDesc.set(Some(JS::PropertyDescriptor::Data(
+ value,
+ {JS::PropertyAttribute::Configurable, JS::PropertyAttribute::Writable,
+ JS::PropertyAttribute::Enumerable})));
+ return true;
+ }
+ return ForwardingProxyHandler::getOwnPropertyDescriptor(aCx, aProxy, aId,
+ aDesc);
+}
+
+bool ObservableArrayProxyHandler::has(JSContext* aCx,
+ JS::Handle<JSObject*> aProxy,
+ JS::Handle<JS::PropertyKey> aId,
+ bool* aBp) const {
+ if (aId.get() == s_length_id) {
+ *aBp = true;
+ return true;
+ }
+ uint32_t index = GetArrayIndexFromId(aId);
+ if (IsArrayIndex(index)) {
+ uint32_t length = 0;
+ if (!GetBackingListLength(aCx, aProxy, &length)) {
+ return false;
+ }
+
+ *aBp = (index < length);
+ return true;
+ }
+ return ForwardingProxyHandler::has(aCx, aProxy, aId, aBp);
+}
+
+bool ObservableArrayProxyHandler::ownPropertyKeys(
+ JSContext* aCx, JS::Handle<JSObject*> aProxy,
+ JS::MutableHandleVector<jsid> aProps) const {
+ uint32_t length = 0;
+ if (!GetBackingListLength(aCx, aProxy, &length)) {
+ return false;
+ }
+
+ for (int32_t i = 0; i < int32_t(length); i++) {
+ if (!aProps.append(JS::PropertyKey::Int(i))) {
+ return false;
+ }
+ }
+ return ForwardingProxyHandler::ownPropertyKeys(aCx, aProxy, aProps);
+}
+
+bool ObservableArrayProxyHandler::preventExtensions(
+ JSContext* aCx, JS::Handle<JSObject*> aProxy,
+ JS::ObjectOpResult& aResult) const {
+ return aResult.failCantPreventExtensions();
+}
+
+bool ObservableArrayProxyHandler::set(JSContext* aCx,
+ JS::Handle<JSObject*> aProxy,
+ JS::Handle<JS::PropertyKey> aId,
+ JS::Handle<JS::Value> aV,
+ JS::Handle<JS::Value> aReceiver,
+ JS::ObjectOpResult& aResult) const {
+ if (aId.get() == s_length_id) {
+ JS::Rooted<JSObject*> backingListObj(aCx);
+ if (!GetBackingListObject(aCx, aProxy, &backingListObj)) {
+ return false;
+ }
+
+ return SetLength(aCx, aProxy, backingListObj, aV, aResult);
+ }
+ uint32_t index = GetArrayIndexFromId(aId);
+ if (IsArrayIndex(index)) {
+ JS::Rooted<JSObject*> backingListObj(aCx);
+ if (!GetBackingListObject(aCx, aProxy, &backingListObj)) {
+ return false;
+ }
+
+ return SetIndexedValue(aCx, aProxy, backingListObj, index, aV, aResult);
+ }
+ return ForwardingProxyHandler::set(aCx, aProxy, aId, aV, aReceiver, aResult);
+}
+
+bool ObservableArrayProxyHandler::GetBackingListObject(
+ JSContext* aCx, JS::Handle<JSObject*> aProxy,
+ JS::MutableHandle<JSObject*> aBackingListObject) const {
+ // Retrieve the backing list object from the reserved slot on the proxy
+ // object. If it doesn't exist yet, create it.
+ JS::Rooted<JS::Value> slotValue(aCx);
+ slotValue = js::GetProxyReservedSlot(
+ aProxy, OBSERVABLE_ARRAY_BACKING_LIST_OBJECT_SLOT);
+ if (slotValue.isUndefined()) {
+ JS::Rooted<JSObject*> newBackingListObj(aCx);
+ newBackingListObj.set(JS::NewArrayObject(aCx, 0));
+ if (NS_WARN_IF(!newBackingListObj)) {
+ return false;
+ }
+ slotValue = JS::ObjectValue(*newBackingListObj);
+ js::SetProxyReservedSlot(aProxy, OBSERVABLE_ARRAY_BACKING_LIST_OBJECT_SLOT,
+ slotValue);
+ }
+ aBackingListObject.set(&slotValue.toObject());
+ return true;
+}
+
+bool ObservableArrayProxyHandler::GetBackingListLength(
+ JSContext* aCx, JS::Handle<JSObject*> aProxy, uint32_t* aLength) const {
+ JS::Rooted<JSObject*> backingListObj(aCx);
+ if (!GetBackingListObject(aCx, aProxy, &backingListObj)) {
+ return false;
+ }
+
+ return JS::GetArrayLength(aCx, backingListObj, aLength);
+}
+
+bool ObservableArrayProxyHandler::SetLength(JSContext* aCx,
+ JS::Handle<JSObject*> aProxy,
+ uint32_t aLength) const {
+ JS::Rooted<JSObject*> backingListObj(aCx);
+ if (!GetBackingListObject(aCx, aProxy, &backingListObj)) {
+ return false;
+ }
+
+ JS::ObjectOpResult result;
+ if (!SetLength(aCx, aProxy, backingListObj, aLength, result)) {
+ return false;
+ }
+
+ return result ? true : result.reportError(aCx, aProxy);
+}
+
+bool ObservableArrayProxyHandler::SetLength(JSContext* aCx,
+ JS::Handle<JSObject*> aProxy,
+ JS::Handle<JSObject*> aBackingList,
+ uint32_t aLength,
+ JS::ObjectOpResult& aResult) const {
+ uint32_t oldLen;
+ if (!JS::GetArrayLength(aCx, aBackingList, &oldLen)) {
+ return false;
+ }
+
+ if (aLength > oldLen) {
+ return aResult.failBadArrayLength();
+ }
+
+ bool ok = true;
+ uint32_t len = oldLen;
+ for (; len > aLength; len--) {
+ uint32_t indexToDelete = len - 1;
+ JS::Rooted<JS::Value> value(aCx);
+ if (!JS_GetElement(aCx, aBackingList, indexToDelete, &value)) {
+ ok = false;
+ break;
+ }
+
+ if (!OnDeleteItem(aCx, aProxy, value, indexToDelete)) {
+ ok = false;
+ break;
+ }
+ }
+
+ return JS::SetArrayLength(aCx, aBackingList, len) && ok ? aResult.succeed()
+ : false;
+}
+
+bool ObservableArrayProxyHandler::SetLength(JSContext* aCx,
+ JS::Handle<JSObject*> aProxy,
+ JS::Handle<JSObject*> aBackingList,
+ JS::Handle<JS::Value> aValue,
+ JS::ObjectOpResult& aResult) const {
+ uint32_t uint32Len;
+ if (!ToUint32(aCx, aValue, &uint32Len)) {
+ return false;
+ }
+
+ double numberLen;
+ if (!ToNumber(aCx, aValue, &numberLen)) {
+ return false;
+ }
+
+ if (uint32Len != numberLen) {
+ JS_ReportErrorNumberASCII(aCx, js::GetErrorMessage, nullptr,
+ JSMSG_BAD_INDEX);
+ return false;
+ }
+
+ return SetLength(aCx, aProxy, aBackingList, uint32Len, aResult);
+}
+
+} // namespace mozilla::dom