From c498cfb2114ace22193f2761a23ae447d32799ec Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jonatan=20K=C5=82osko?= <jonatanklosko@gmail.com>
Date: Wed, 21 Apr 2021 17:38:48 +0200
Subject: [PATCH] Explicitly dispose Monaco editor instance when cell is
 deleted (#232)

---
 assets/js/cell/index.js       |  4 ++++
 assets/js/cell/live_editor.js | 14 ++++++++++++++
 2 files changed, 18 insertions(+)

diff --git a/assets/js/cell/index.js b/assets/js/cell/index.js
index 63b5d6249..e887dc7dd 100644
--- a/assets/js/cell/index.js
+++ b/assets/js/cell/index.js
@@ -83,6 +83,10 @@ const Cell = {
 
   destroyed() {
     globalPubSub.unsubscribe("session", this.handleSessionEvent);
+
+    if (this.state.liveEditor) {
+      this.state.liveEditor.destroy();
+    }
   },
 
   updated() {
diff --git a/assets/js/cell/live_editor.js b/assets/js/cell/live_editor.js
index 1135d9503..839d460be 100644
--- a/assets/js/cell/live_editor.js
+++ b/assets/js/cell/live_editor.js
@@ -71,6 +71,20 @@ class LiveEditor {
       .pushEditOperations([], [{ forceMoveMarkers: true, range, text }]);
   }
 
+  /**
+   * Performs necessary cleanup actions.
+   */
+  destroy() {
+    // Explicitly destroy the editor instance and its text model.
+    this.editor.dispose();
+
+    const model = this.editor.getModel();
+
+    if (model) {
+      model.dispose();
+    }
+  }
+
   __mountEditor() {
     this.editor = monaco.editor.create(this.container, {
       language: this.type,