1 files changed, 91 insertions, 0 deletions
diff --git a/editor/libeditor/ChangeAttributeTransaction.h b/editor/libeditor/ChangeAttributeTransaction.h
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+++ b/editor/libeditor/ChangeAttributeTransaction.h
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+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 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/. */
+
+#ifndef ChangeAttributeTransaction_h
+#define ChangeAttributeTransaction_h
+
+#include "EditTransactionBase.h"  // base class
+
+#include "mozilla/Attributes.h"            // override
+#include "nsCOMPtr.h"                      // nsCOMPtr members
+#include "nsCycleCollectionParticipant.h"  // NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED
+#include "nsISupportsImpl.h"               // NS_DECL_ISUPPORTS_INHERITED
+#include "nsString.h"                      // nsString members
+
+class nsAtom;
+
+namespace mozilla {
+namespace dom {
+class Element;
+}  // namespace dom
+
+/**
+ * A transaction that changes an attribute of a content node.  This transaction
+ * covers add, remove, and change attribute.
+ */
+class ChangeAttributeTransaction final : public EditTransactionBase {
+ protected:
+  ChangeAttributeTransaction(dom::Element& aElement, nsAtom& aAttribute,
+                             const nsAString* aValue);
+
+ public:
+  /**
+   * Creates a change attribute transaction to set an attribute to something.
+   * This method never returns nullptr.
+   *
+   * @param aElement    The element whose attribute will be changed.
+   * @param aAttribute  The name of the attribute to change.
+   * @param aValue      The new value for aAttribute.
+   */
+  static already_AddRefed<ChangeAttributeTransaction> Create(
+      dom::Element& aElement, nsAtom& aAttribute, const nsAString& aValue);
+
+  /**
+   * Creates a change attribute transaction to remove an attribute.  This
+   * method never returns nullptr.
+   *
+   * @param aElement    The element whose attribute will be changed.
+   * @param aAttribute  The name of the attribute to remove.
+   */
+  static already_AddRefed<ChangeAttributeTransaction> CreateToRemove(
+      dom::Element& aElement, nsAtom& aAttribute);
+
+  NS_DECL_ISUPPORTS_INHERITED
+  NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(ChangeAttributeTransaction,
+                                           EditTransactionBase)
+
+  NS_DECL_EDITTRANSACTIONBASE
+  NS_DECL_EDITTRANSACTIONBASE_GETASMETHODS_OVERRIDE(ChangeAttributeTransaction)
+
+  MOZ_CAN_RUN_SCRIPT NS_IMETHOD RedoTransaction() override;
+
+  friend std::ostream& operator<<(
+      std::ostream& aStream, const ChangeAttributeTransaction& aTransaction);
+
+ private:
+  virtual ~ChangeAttributeTransaction() = default;
+
+  // The element to operate upon
+  nsCOMPtr<dom::Element> mElement;
+
+  // The attribute to change
+  RefPtr<nsAtom> mAttribute;
+
+  // The value to set the attribute to (ignored if mRemoveAttribute==true)
+  nsString mValue;
+
+  // The value to set the attribute to for undo
+  nsString mUndoValue;
+
+  // True if the operation is to remove mAttribute from mElement
+  bool mRemoveAttribute;
+
+  // True if the mAttribute was set on mElement at the time of execution
+  bool mAttributeWasSet;
+};
+
+}  // namespace mozilla
+
+#endif  // #ifndef ChangeAttributeTransaction_h