Plugins: Add support for joplin.workspace.filterEditorContextMenu to allow dynamically setting editor menu items depending on context

packages/app-desktop/gui/NoteEditor/NoteBody/CodeMirror/CodeMirror.tsx

@@ -36,6 +36,8 @@ const MenuItem = bridge().MenuItem;
 import { reg } from '@joplin/lib/registry';
 import ErrorBoundary from '../../../ErrorBoundary';
 import { MarkupToHtmlOptions } from '../../utils/useMarkupToHtml';
+import eventManager from '@joplin/lib/eventManager';
+import { EditContextMenuFilterObject } from '@joplin/lib/services/plugins/api/JoplinWorkspace';
 
 const menuUtils = new MenuUtils(CommandService.instance());
 
@@ -733,7 +735,7 @@ function CodeMirror(props: NoteBodyEditorProps, ref: any) {
 			return rect.x < x && rect.y < y && rect.right > x && rect.bottom > y;
 		}
 
-		function onContextMenu(_event: any, params: any) {
+		async function onContextMenu(_event: any, params: any) {
 			if (!pointerInsideEditor(params.x, params.y)) return;
 
 			const menu = new Menu();
@@ -787,6 +789,23 @@ function CodeMirror(props: NoteBodyEditorProps, ref: any) {
 				editorRef.current.alignSelection(params);
 			}
 
+			let filterObject: EditContextMenuFilterObject = {
+				items: [],
+			};
+
+			filterObject = await eventManager.filterEmit('editorContextMenu', filterObject);
+
+			for (const item of filterObject.items) {
+				menu.append(new MenuItem({
+					label: item.label,
+					click: async () => {
+						const args = item.commandArgs || [];
+						void CommandService.instance().execute(item.commandName, ...args);
+					},
+					type: item.type,
+				}));
+			}
+
 			menuUtils.pluginContextMenuItems(props.plugins, MenuItemLocation.EditorContextMenu).forEach((item: any) => {
 				menu.append(new MenuItem(item));
 			});

packages/app-desktop/testPluginDemo.sh

@@ -4,5 +4,5 @@
 # It could be used to develop plugins too.
 
 SCRIPT_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )"
-PLUGIN_PATH="$SCRIPT_DIR/../app-cli/tests/support/plugins/toc"
-yarn i --prefix="$PLUGIN_PATH" && yarn start --dev-plugins "$PLUGIN_PATH"
+PLUGIN_PATH=~/src/joplin-rich-markdown
+npm install --prefix="$PLUGIN_PATH" && yarn start --dev-plugins "$PLUGIN_PATH"

packages/lib/eventManager.ts

@@ -1,3 +1,5 @@
+const fastDeepEqual = require('fast-deep-equal');
+
 const events = require('events');
 
 export class EventManager {
@@ -43,21 +45,22 @@ export class EventManager {
 		return this.removeListener(`filter:${filterName}`, callback);
 	}
 
-	filterEmit(filterName: string, object: any) {
-		// We freeze the object we pass to the listeners so that they
-		// don't modify it directly. Instead they must return a
-		// modified copy (or the input itself).
-		let output = Object.freeze(object);
+	public async filterEmit(filterName: string, object: any) {
+		let output = object;
 		const listeners = this.emitter_.listeners(`filter:${filterName}`);
 		for (const listener of listeners) {
-			const newOutput = listener(output);
+			// When we pass the object to the plugin, it is always going to be
+			// modified since it is serialized/unserialized. So we need to use a
+			// deep equality check to see if it's been changed. Normally the
+			// filter objects should be relatively small so there shouldn't be
+			// much of a performance hit.
+			const newOutput = await listener(output);
 
-			if (newOutput === undefined) {
-				throw new Error(`Filter "${filterName}": Filter must return a value or the unmodified input. Returning nothing or "undefined" is not supported.`);
-			}
+			// Plugin didn't return anything - so we leave the object as it is.
+			if (newOutput === undefined) continue;
 
-			if (newOutput !== output) {
-				output = Object.freeze(newOutput);
+			if (!fastDeepEqual(newOutput, output)) {
+				output = newOutput;
 			}
 		}
 

packages/lib/services/plugins/api/JoplinWorkspace.ts

@@ -3,7 +3,7 @@ import eventManager from '../../../eventManager';
 import Setting from '../../../models/Setting';
 import { FolderEntity } from '../../database/types';
 import makeListener from '../utils/makeListener';
-import { Disposable } from './types';
+import { Disposable, MenuItem } from './types';
 
 /**
  * @ignore
@@ -15,6 +15,12 @@ import Note from '../../../models/Note';
  */
 import Folder from '../../../models/Folder';
 
+export interface EditContextMenuFilterObject {
+	items: MenuItem[];
+}
+
+type FilterHandler<T> = (object: T)=> Promise<void>;
+
 enum ItemChangeEventType {
 	Create = 1,
 	Update = 2,
@@ -113,6 +119,14 @@ export default class JoplinWorkspace {
 		return makeListener(eventManager, 'syncComplete', callback);
 	}
 
+	/**
+	 * Called just before the editor context menu is about to open. Allows
+	 * adding items to it.
+	 */
+	public filterEditorContextMenu(handler: FilterHandler<EditContextMenuFilterObject>) {
+		eventManager.filterOn('editorContextMenu', handler);
+	}
+
 	/**
 	 * Gets the currently selected note
 	 */
@@ -139,4 +153,5 @@ export default class JoplinWorkspace {
 	public async selectedNoteIds(): Promise<string[]> {
 		return this.store.getState().selectedNoteIds.slice();
 	}
+
 }

packages/lib/services/plugins/api/types.ts

@@ -269,6 +269,17 @@ export interface MenuItem {
 	 */
 	commandName?: string;
 
+	/**
+	 * Arguments that should be passed to the command. They will be as rest
+	 * parameters.
+	 */
+	commandArgs?: any[];
+
+	/**
+	 * Set to "separator" to create a divider line
+	 */
+	type?: string;
+
 	/**
 	 * Accelerator associated with the menu item
 	 */