fix change session by moving to async/await promise (#1927)

* fix change session by moving to async/await promise

* add test that tests settings update

Author: TylerLeonhardt

src/settings.ts

@@ -192,12 +192,12 @@ export function load(): ISettings {
     };
 }
 
-export function change(settingName: string, newValue: any, global: boolean = false): Thenable<void> {
+export async function change(settingName: string, newValue: any, global: boolean = false): Promise<void> {
     const configuration: vscode.WorkspaceConfiguration =
         vscode.workspace.getConfiguration(
             utils.PowerShellLanguageId);
 
-    return configuration.update(settingName, newValue, global);
+    await configuration.update(settingName, newValue, global);
 }
 
 function getWorkspaceSettingsWithDefaults<TSettings>(

test/settings.test.ts

@@ -19,4 +19,14 @@ suite("Settings module", () => {
             assert.deepEqual(settings.developer.featureFlags, []);
         }
     });
+
+    test("Settings update correctly", async () => {
+        // then syntax
+        Settings.change("powerShellExePath", "dummypath1", false).then(() =>
+            assert.strictEqual(Settings.load().powerShellExePath, "dummypath1"));
+
+        // async/await syntax
+        await Settings.change("powerShellExePath", "dummypath2", false);
+        assert.strictEqual(Settings.load().powerShellExePath, "dummypath2");
+    });
 });