Extract emmet loading boilerplate

src/vs/workbench/parts/emmet/node/emmetActions.ts

@@ -22,19 +22,37 @@ interface IEmmetConfiguration {
 	};
 }
 
-export abstract class EmmetEditorAction extends EditorAction {
+class LazyEmmet {
 
-	protected editorAccessor: EditorAccessor;
-	private configurationService: IConfigurationService = null;
+	private static _INSTANCE = new LazyEmmet();
 
-	constructor(descriptor: IEditorActionDescriptorData, editor: ICommonCodeEditor, configurationService: IConfigurationService) {
-		super(descriptor, editor, Behaviour.Writeable);
-		this.editorAccessor = new EditorAccessor(editor);
-		this.configurationService = configurationService;
+	public static withConfiguredEmmet(configurationService:IConfigurationService, callback:(_emmet: typeof emmet) => void): TPromise<void> {
+		return LazyEmmet._INSTANCE.withEmmetPreferences(configurationService, callback);
+	}
+
+	private _emmetPromise: TPromise<typeof emmet>;
+
+	constructor() {
+		this._emmetPromise = null;
 	}
 
-	private updateEmmetPreferences(_emmet: typeof emmet) {
-		let preferences = this.configurationService.getConfiguration<IEmmetConfiguration>().emmet.preferences;
+	public withEmmetPreferences(configurationService:IConfigurationService, callback:(_emmet: typeof emmet) => void): TPromise<void> {
+		return this._loadEmmet().then((_emmet: typeof emmet) => {
+			this._withEmmetPreferences(configurationService, _emmet, callback);
+		});
+	}
+
+	private _loadEmmet(): TPromise<typeof emmet> {
+		if (!this._emmetPromise) {
+			this._emmetPromise = new TPromise<typeof emmet>((c, e) => {
+				require(['emmet'], c, e);
+			});
+		}
+		return this._emmetPromise;
+	}
+
+	private updateEmmetPreferences(configurationService:IConfigurationService, _emmet: typeof emmet) {
+		let preferences = configurationService.getConfiguration<IEmmetConfiguration>().emmet.preferences;
 		for (let key in preferences) {
 			try {
 				_emmet.preferences.set(key, preferences[key]);
@@ -42,13 +60,13 @@ export abstract class EmmetEditorAction extends EditorAction {
 				_emmet.preferences.define(key, preferences[key]);
 			}
 		}
-		let syntaxProfile = this.configurationService.getConfiguration<IEmmetConfiguration>().emmet.syntaxProfiles;
+		let syntaxProfile = configurationService.getConfiguration<IEmmetConfiguration>().emmet.syntaxProfiles;
 		_emmet.profile.reset();
 		_emmet.loadProfiles(syntaxProfile);
 	}
 
-	private resetEmmetPreferences(_emmet: typeof emmet) {
-		let preferences = this.configurationService.getConfiguration<IEmmetConfiguration>().emmet.preferences;
+	private resetEmmetPreferences(configurationService:IConfigurationService, _emmet: typeof emmet) {
+		let preferences = configurationService.getConfiguration<IEmmetConfiguration>().emmet.preferences;
 		for (let key in preferences) {
 			try {
 				_emmet.preferences.remove(key);
@@ -57,42 +75,44 @@ export abstract class EmmetEditorAction extends EditorAction {
 		}
 	}
 
+	private _withEmmetPreferences(configurationService:IConfigurationService, _emmet:typeof emmet, callback:(_emmet: typeof emmet) => void): void {
+		try {
+			this.updateEmmetPreferences(configurationService, _emmet);
+			callback(_emmet);
+		} finally {
+			this.resetEmmetPreferences(configurationService, _emmet);
+		}
+	}
+}
+
+export abstract class EmmetEditorAction extends EditorAction {
+
+	protected editorAccessor: EditorAccessor;
+	private configurationService: IConfigurationService = null;
+
+	constructor(descriptor: IEditorActionDescriptorData, editor: ICommonCodeEditor, configurationService: IConfigurationService) {
+		super(descriptor, editor, Behaviour.Writeable);
+		this.editorAccessor = new EditorAccessor(editor);
+		this.configurationService = configurationService;
+	}
+
 	abstract runEmmetAction(_emmet: typeof emmet);
 
 	protected noExpansionOccurred() {
 		// default do nothing
 	}
 
-	public run(): TPromise<boolean> {
+	public run(): TPromise<void> {
 		if (!this.editorAccessor.isEmmetEnabledMode()) {
 			this.noExpansionOccurred();
 			return ;
 		}
 
-		return this._withEmmet().then((_emmet) => {
-			this._withEmmetPreferences(_emmet, () => {
+		return LazyEmmet.withConfiguredEmmet(this.configurationService, (_emmet) => {
 			this.editorAccessor.onBeforeEmmetAction();
 			this.runEmmetAction(_emmet);
 			this.editorAccessor.onAfterEmmetAction();
 		});
-
-			return true;
-		});
-	}
-
-	private _withEmmet(): TPromise<typeof emmet> {
-		return new TPromise<typeof emmet>((c, e) => {
-			require(['emmet'], c, e);
-		});
-	}
-
-	private _withEmmetPreferences(_emmet:typeof emmet, callback:() => void): void {
-		try {
-			this.updateEmmetPreferences(_emmet);
-			callback();
-		} finally {
-			this.resetEmmetPreferences(_emmet);
-		}
 	}
 }