Fix bug where checker could be opened twice and delete nodes (#138)

* Fix bug where checker could be opened twice and delete nodes

Prevents opening the checker while it is already open, which could cause nodes to be deleted

closes MAT-1106

Test Plan:
- Open an RCE and create content that causes an a11y violation
- Click the a11y checker icon to open the a11y checker
- Check the box to apply formatting changes
- Click the a11y checker icon to Open the a11y checker again (without closing it)
- Verify RCE content is not changed, RCE can be edited and used as normal
- Verify a11y checker can be opened again, used as normal

* Update version and changelog

* Update CHANGELOG for real

packages/canvas-rce/src/tinymce-a11y-checker/CHANGELOG.md

@@ -7,7 +7,12 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
-## [4.2.3] - 2023-01-30
+## [4.1.4] - 2023-02-14
+
+- Fixed a bug where the a11y checker could be opened twice and cause
+  content to become deleted
+
+## [4.1.3] - 2023-01-30
 
 - Change the violation highlight from an absolutely positioned blue box
   to an outline created with just CSS

packages/canvas-rce/src/tinymce-a11y-checker/package.json

@@ -1,6 +1,6 @@
 {
   "name": "tinymce-a11y-checker",
-  "version": "4.1.3",
+  "version": "4.1.4",
   "description": "An accessibility checker plugin for TinyMCE.",
   "main": "lib/plugin.js",
   "module": "es/plugin.js",

packages/canvas-rce/src/tinymce-a11y-checker/src/components/checker.js

@@ -53,7 +53,9 @@ export default class Checker extends React.Component {
 
   componentDidMount() {
     this.props.editor.on("Remove", (editor) => {
-      this.setState({ open: false })
+      this.setState({ open: false },  () => {
+        this.props.onClose()
+      })
     })
   }
 
@@ -282,7 +284,9 @@ export default class Checker extends React.Component {
   handleClose() {
     this.onLeaveError()
     clearIndicators(this.props.editor.dom.doc)
-    this.setState({ open: false })
+    this.setState({ open: false },  () => {
+      this.props.onClose()
+    })
   }
 
   render() {

packages/canvas-rce/src/tinymce-a11y-checker/src/plugin.js

@@ -4,6 +4,7 @@ import Checker from "./components/checker"
 import formatMessage from "./format-message"
 import checkNode from "./node-checker"
 
+let isCheckerOpen = false
 let instance
 const pendingInstanceCallbacks = []
 const container = document.createElement("div")
@@ -16,25 +17,29 @@ tinymce.create("tinymce.plugins.AccessibilityChecker", {
       ui,
       { done, config, additionalRules, mountNode }
     ) {
-      ReactDOM.render(
-        <Checker
-          getBody={ed.getBody.bind(ed)}
-          editor={ed}
-          additionalRules={additionalRules}
-          mountNode={mountNode}
-        />,
-        container,
-        function () {
-          // this is a workaround for react 16 since ReactDOM.render is not
-          // guaranteed to return the instance synchronously (especially if called
-          // within another component's lifecycle method eg: componentDidMount). see:
-          // https://github.com/facebook/react/issues/10309#issuecomment-318434635
-          instance = this
-          if (config) getInstance(instance => instance.setConfig(config))
-          pendingInstanceCallbacks.forEach(cb => cb(instance))
-          instance.check(done)
-        }
-      )
+      if (!isCheckerOpen) {
+        ReactDOM.render(
+          <Checker
+            getBody={ed.getBody.bind(ed)}
+            editor={ed}
+            additionalRules={additionalRules}
+            mountNode={mountNode}
+            onClose={() => isCheckerOpen = false}
+          />,
+          container,
+          function () {
+            // this is a workaround for react 16 since ReactDOM.render is not
+            // guaranteed to return the instance synchronously (especially if called
+            // within another component's lifecycle method eg: componentDidMount). see:
+            // https://github.com/facebook/react/issues/10309#issuecomment-318434635
+            instance = this
+            if (config) getInstance(instance => instance.setConfig(config))
+            pendingInstanceCallbacks.forEach(cb => cb(instance))
+            instance.check(done)
+          }
+        )
+        isCheckerOpen = true
+      }
     })
 
     ed.addCommand("checkAccessibility", function (