Prevent beforeunload actions when downloading files

Previously, downloading a file would also trigger the beforeunload action and thereby remove the ACE editor or JsTree objects. Now, we prevent this by removing the `beforeunload` event listener and reinstalling it after "navigation".

Author: MrSerth

app/assets/javascripts/editor/editor.js

@@ -428,19 +428,22 @@ var CodeOceanEditor = {
         const jsTree = filesInstance?.jstree(true);
         $(document).on('theme:change', themeListener);
         $(document).one('turbo:visit', function() {
-            $(document).off('theme:change', themeListener);
-            if (jsTree && jsTree.element) {
-                jsTree.destroy(true);
-            }
+            CodeOceanEditor.removeFileTreeEventHandlers(filesInstance);
         });
         $(window).one('beforeunload', function() {
-            $(document).off('theme:change', themeListener);
-            if (jsTree && jsTree.element) {
-                jsTree.destroy(true);
-            }
+            CodeOceanEditor.removeFileTreeEventHandlers(filesInstance);
         });
     },
 
+    removeFileTreeEventHandlers: function (filesInstance) {
+        const themeListener = this.createFileTreeThemeChangeListener(filesInstance);
+        const jsTree = filesInstance?.jstree(true);
+        $(document).off('theme:change', themeListener);
+        if (jsTree && jsTree.element) {
+            jsTree.destroy(true);
+        }
+    },
+
     createFileTreeThemeChangeListener: function (filesInstance) {
       return function (event) {
             const jsTree = filesInstance?.jstree(true);
@@ -853,7 +856,9 @@ var CodeOceanEditor = {
             selected.instance.deselect_all();
             const downloadPath = selected.node.original.download_path;
             if (downloadPath) {
+                $(window).off("beforeunload");
                 window.location = downloadPath;
+                $(window).one("beforeunload", this.unloadEverything.bind(this, App.synchronized_editor));
             }
         }.bind(this));
         $('#download-files').removeClass('d-none');

app/assets/javascripts/editor/submissions.js

@@ -102,9 +102,11 @@ CodeOceanEditorSubmissions = {
     const submission = await this.createSubmission('#download', null).catch(this.ajaxError.bind(this));
     if(!submission) return;
 
+    $(window).off("beforeunload");
     // to download just a single file, use the following url
     // window.location = Routes.download_file_submission_url(submission.id, CodeOceanEditor.active_file.filename);
     window.location = Routes.download_submission_url(submission.id);
+    $(window).one("beforeunload", this.unloadEverything.bind(this, App.synchronized_editor));
   },
 
   resetCode: function(initiator, onlyActiveFile = false) {

app/assets/javascripts/shell.js

@@ -130,7 +130,11 @@ $(document).on('turbo-migration:load', function () {
                         text: I18n.t('execution_environments.shell.file_tree.permission_denied')
                     });
                 } else {
+                    $(window).off('beforeunload');
                     window.location = downloadPath;
+                    $(window).one('beforeunload', function () {
+                        CodeOceanEditor.removeFileTreeEventHandlers(fileTree);
+                    })
                 }
             }.bind(this));
             CodeOceanEditor.installFileTreeEventHandlers(fileTree);