From 7768fa5625274c03c2a62bd284d696951c5bcd19 Mon Sep 17 00:00:00 2001
From: Kameron Niksefat <kameron.niksefat@gmail.com>
Date: Thu, 19 May 2022 09:12:47 -0400
Subject: [PATCH] add willPaste event

---
 README.md                                  |  2 ++
 src/js/editor/editor.ts                    |  9 ++++++++
 src/js/editor/event-manager.ts             |  2 ++
 tests/acceptance/editor-copy-paste-test.js | 24 ++++++++++++++++++++++
 4 files changed, 37 insertions(+)

diff --git a/README.md b/README.md
index 3e50f8b4b..c727454e1 100644
--- a/README.md
+++ b/README.md
@@ -229,6 +229,8 @@ The available lifecycle hooks are:
 * `editor.willCopy(({html, text, mobiledoc}) => {...})` - Called before the
   serialized versions of the selected markup is copied to the system
   pasteboard.
+  `editor.willPaste(({html, text, mobiledoc}) => {...})` - Called before the
+  serialized versions of the system pasteboard is pasted into the mobiledoc.
 
 For more details on the lifecycle hooks, see the [Editor documentation](https://bustle.github.io/mobiledoc-kit/demo/docs/Editor.html).
 
diff --git a/src/js/editor/editor.ts b/src/js/editor/editor.ts
index 22608c5f2..8d9471e93 100644
--- a/src/js/editor/editor.ts
+++ b/src/js/editor/editor.ts
@@ -109,6 +109,7 @@ const CALLBACK_QUEUES = {
   POST_DID_CHANGE: 'postDidChange',
   INPUT_MODE_DID_CHANGE: 'inputModeDidChange',
   WILL_COPY: 'willCopy',
+  WILL_PASTE: 'willPaster',
 }
 
 export enum Format {
@@ -961,6 +962,14 @@ export default class Editor implements EditorOptions {
     this.addCallback(CALLBACK_QUEUES.WILL_COPY, callback)
   }
 
+  /**
+   * @param {Function} callback This callback will be called before pasting.
+   * @public
+   */
+  willPaste(callback: LifecycleCallback) {
+    this.addCallback(CALLBACK_QUEUES.WILL_PASTE, callback)
+  }
+
   /**
    * @param {Function} callback This callback will be called before deleting.
    * @public
diff --git a/src/js/editor/event-manager.ts b/src/js/editor/event-manager.ts
index 70c28c01b..3ee3518ab 100644
--- a/src/js/editor/event-manager.ts
+++ b/src/js/editor/event-manager.ts
@@ -369,6 +369,8 @@ export default class EventManager {
     let targetFormat = this.modifierKeys.shift ? 'text' : 'html'
     let pastedPost = parsePostFromPaste(event, editor, { targetFormat })
 
+    editor.runCallbacks('willPaste', [pastedPost])
+
     editor.run(postEditor => {
       let nextPosition = postEditor.insertPost(position, pastedPost!)
       postEditor.setRange(nextPosition)
diff --git a/tests/acceptance/editor-copy-paste-test.js b/tests/acceptance/editor-copy-paste-test.js
index 2562e00ca..7a9be0430 100644
--- a/tests/acceptance/editor-copy-paste-test.js
+++ b/tests/acceptance/editor-copy-paste-test.js
@@ -141,6 +141,30 @@ test('willCopy callback called before copy', (assert) => {
   Helpers.dom.triggerCopyEvent(editor);
 });
 
+test('willPaste callback called before paste', assert => {
+  const mobiledoc = Helpers.mobiledoc.build(({ post, markupSection, marker, markup }) => {
+    return post([markupSection('p', [marker('a', [markup('strong')]), marker('bc')])])
+  })
+  editor = new Editor({ mobiledoc })
+  editor.addCallback('willPaste', post => {
+    assert.equal(post.sections.head.text, 'bc')
+  })
+  editor.render(editorElement)
+
+  Helpers.dom.selectText(editor, 'a', editorElement, 'b', editorElement)
+  Helpers.dom.triggerCopyEvent(editor)
+
+  let textNode = $('#editor p')[0].childNodes[1]
+  assert.equal(textNode.textContent, 'bc') //precond
+  Helpers.dom.moveCursorTo(editor, textNode, textNode.length)
+
+  Helpers.dom.triggerPasteEvent(editor)
+
+  assert.hasElement('#editor p:contains(abcab)', 'pastes the text')
+  assert.equal($('#editor p strong:contains(a)').length, 2, 'two bold As')
+})
+
+
 test('can cut and then paste content', (assert) => {
   const mobiledoc = Helpers.mobiledoc.build(
     ({post, markupSection, marker}) => {