Use CachingLocator.

src/client/pythonEnvironments/index.ts

@@ -6,6 +6,7 @@ import { IServiceContainer, IServiceManager } from '../ioc/types';
 import { PythonEnvInfo } from './base/info';
 import { ILocator, IPythonEnvsIterator, PythonLocatorQuery } from './base/locator';
 import { PythonEnvsChangedEvent } from './base/watcher';
+import { CachingLocator } from './collection/cachingLocator';
 import { ExtensionLocators, WorkspaceLocators } from './discovery/locators';
 import { registerForIOC } from './legacyIOC';
 
@@ -49,11 +50,14 @@ export class PythonEnvironments implements ILocator {
  */
 export function createAPI(): [PythonEnvironments, () => void] {
     const [locators, activateLocators] = initLocators();
+    const cache = {}; // This will be filled in once we have it.
+    const cachingLocator = new CachingLocator(cache!, locators);
 
     return [
-        new PythonEnvironments(locators),
+        new PythonEnvironments(cachingLocator),
         () => {
             activateLocators();
+            cachingLocator.initialize().ignoreErrors();
             // Any other activation needed for the API will go here later.
         }
     ];