Initialize/activate the ExtensionLocators when the extension activates.

src/client/extensionInit.ts

@@ -12,7 +12,7 @@ import { GLOBAL_MEMENTO, IDisposableRegistry, IExtensionContext, IMemento, WORKS
 import { ServiceContainer } from './ioc/container';
 import { ServiceManager } from './ioc/serviceManager';
 import { IServiceContainer, IServiceManager } from './ioc/types';
-import { registerForIOC } from './pythonEnvironments/legacyIOC';
+import { activate as activatePythonEnvironments } from './pythonEnvironments';
 
 // The code in this module should do nothing more complex than register
 // objects to DI and simple init (e.g. no side effects).  That implies
@@ -40,6 +40,6 @@ export function initializeComponents(
     serviceManager: IServiceManager,
     serviceContainer: IServiceContainer
 ) {
-    registerForIOC(serviceManager, serviceContainer);
+    activatePythonEnvironments(serviceManager, serviceContainer);
     // We will be pulling code over from activateLegacy().
 }

src/client/pythonEnvironments/index.ts

@@ -0,0 +1,58 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+import * as vscode from 'vscode';
+import { IServiceContainer, IServiceManager } from '../ioc/types';
+import { ILocator } from './base/locator';
+import { ExtensionLocators, WorkspaceLocators } from './discovery/locators';
+import { registerForIOC } from './legacyIOC';
+
+export function activate(serviceManager: IServiceManager, serviceContainer: IServiceContainer) {
+    registerForIOC(serviceManager, serviceContainer);
+
+    const [locators, activateLocators] = initLocators();
+    activateLocators();
+    // We will pass the locators into the component API.
+    // tslint:disable-next-line:no-unused-expression
+    locators;
+}
+
+function initLocators(): [ExtensionLocators, () => void] {
+    // We will add locators in similar order
+    // to PythonInterpreterLocatorService.getLocators().
+    const nonWorkspaceLocators: ILocator[] = [
+        // Add an ILocator object here for each non-workspace locator.
+    ];
+
+    const workspaceLocators = new WorkspaceLocators([
+        // Add an ILocator factory func here for each kind of workspace-rooted locator.
+    ]);
+
+    return [
+        new ExtensionLocators(nonWorkspaceLocators, workspaceLocators),
+        // combined activation func:
+        () => {
+            // Any non-workspace locator activation goes here.
+            workspaceLocators.activate(getWorkspaceFolders());
+        }
+    ];
+}
+
+function getWorkspaceFolders() {
+    const rootAdded = new vscode.EventEmitter<vscode.Uri>();
+    const rootRemoved = new vscode.EventEmitter<vscode.Uri>();
+    vscode.workspace.onDidChangeWorkspaceFolders((event) => {
+        for (const root of event.removed) {
+            rootRemoved.fire(root.uri);
+        }
+        for (const root of event.added) {
+            rootAdded.fire(root.uri);
+        }
+    });
+    const folders = vscode.workspace.workspaceFolders;
+    return {
+        roots: folders ? folders.map((f) => f.uri) : [],
+        onAdded: rootAdded.event,
+        onRemoved: rootRemoved.event
+    };
+}