Merge from vscode 3d67364fbfcf676d93be64f949e9b33e7f1b969e (#5028)

src/vs/workbench/api/common/extHostMemento.ts

@@ -0,0 +1,59 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+import { IDisposable } from 'vs/base/common/lifecycle';
+import { IExtensionMemento } from 'vs/workbench/api/common/extHostExtensionActivator';
+import { ExtHostStorage } from 'vs/workbench/api/common/extHostStorage';
+
+export class ExtensionMemento implements IExtensionMemento {
+
+	private readonly _id: string;
+	private readonly _shared: boolean;
+	private readonly _storage: ExtHostStorage;
+
+	private readonly _init: Promise<ExtensionMemento>;
+	private _value: { [n: string]: any; };
+	private readonly _storageListener: IDisposable;
+
+	constructor(id: string, global: boolean, storage: ExtHostStorage) {
+		this._id = id;
+		this._shared = global;
+		this._storage = storage;
+
+		this._init = this._storage.getValue(this._shared, this._id, Object.create(null)).then(value => {
+			this._value = value;
+			return this;
+		});
+
+		this._storageListener = this._storage.onDidChangeStorage(e => {
+			if (e.shared === this._shared && e.key === this._id) {
+				this._value = e.value;
+			}
+		});
+	}
+
+	get whenReady(): Promise<ExtensionMemento> {
+		return this._init;
+	}
+
+	get<T>(key: string, defaultValue: T): T {
+		let value = this._value[key];
+		if (typeof value === 'undefined') {
+			value = defaultValue;
+		}
+		return value;
+	}
+
+	update(key: string, value: any): Promise<boolean> {
+		this._value[key] = value;
+		return this._storage
+			.setValue(this._shared, this._id, this._value)
+			.then(() => true);
+	}
+
+	dispose(): void {
+		this._storageListener.dispose();
+	}
+}