Adding upstream version 124.0.1.upstream/124.0.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 372 insertions, 0 deletions

diff --git a/dom/bindings/ObservableArrayProxyHandler.cpp b/dom/bindings/ObservableArrayProxyHandler.cpp
new file mode 100644
index 0000000000..931950a492
--- /dev/null
+++ b/dom/bindings/ObservableArrayProxyHandler.cpp
@@ -0,0 +1,372 @@
+/* -*- 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