config(chat): try opt in implicit @workspace context once for treatment group #6217

## Problem
Most users might have disabled workspace context due to previous
sub-process performance issue, therefore #6098 experiment has too few
datapoints.

## Solution
As we've been actively working on fixes to improve the amazon q helper
sub-process performance, the team decided to try turn on (only once)
workspace context for a small fraction of all users (20%) to collect few
more datapoints.

Author: Will-ShaoHua

packages/core/package.nls.json

@@ -295,6 +295,7 @@
     "AWS.codewhisperer.customization.notification.new_customizations.learn_more": "Learn More",
     "AWS.amazonq.title": "Amazon Q",
     "AWS.amazonq.chat": "Chat",
+    "AWS.amazonq.chat.workspacecontext.enable.message": "Amazon Q: Workspace index is now enabled. You can disable it from Amazon Q settings.",
     "AWS.amazonq.security": "Code Issues",
     "AWS.amazonq.login": "Login",
     "AWS.amazonq.learnMore": "Learn More About Amazon Q",
@@ -404,6 +405,7 @@
     "AWS.amazonq.doc.pillText.reject": "Reject",
     "AWS.amazonq.doc.pillText.makeChanges": "Make changes",
     "AWS.amazonq.inline.invokeChat": "Inline chat",
+    "AWS.amazonq.opensettings:": "Open settings",
     "AWS.toolkit.lambda.walkthrough.quickpickTitle": "Application Builder Walkthrough",
     "AWS.toolkit.lambda.walkthrough.title": "Get started building your application",
     "AWS.toolkit.lambda.walkthrough.description": "Your quick guide to build an application visually, iterate locally, and deploy to the cloud!",

packages/core/src/shared/featureConfig.ts

@@ -10,6 +10,7 @@ import {
     ListFeatureEvaluationsResponse,
 } from '../codewhisperer/client/codewhispereruserclient'
 import * as vscode from 'vscode'
+import * as nls from 'vscode-nls'
 import { codeWhispererClient as client } from '../codewhisperer/client/codewhisperer'
 import { AuthUtil } from '../codewhisperer/util/authUtil'
 import { getLogger } from './logger'
@@ -19,7 +20,9 @@ import globals from './extensionGlobals'
 import { getClientId, getOperatingSystem } from './telemetry/util'
 import { extensionVersion } from './vscode/env'
 import { telemetry } from './telemetry'
-import { Auth } from '../auth'
+import { Commands } from './vscode/commands2'
+
+const localize = nls.loadMessageBundle()
 
 export class FeatureContext {
     constructor(
@@ -35,6 +38,7 @@ export const Features = {
     customizationArnOverride: 'customizationArnOverride',
     dataCollectionFeature: 'IDEProjectContextDataCollection',
     projectContextFeature: 'ProjectContextV2',
+    workspaceContextFeature: 'WorkspaceContext',
     test: 'testFeature',
 } as const
 
@@ -83,6 +87,21 @@ export class FeatureConfigProvider {
         }
     }
 
+    getWorkspaceContextGroup(): 'control' | 'treatment' {
+        const variation = this.featureConfigs.get(Features.projectContextFeature)?.variation
+
+        switch (variation) {
+            case 'CONTROL':
+                return 'control'
+
+            case 'TREATMENT':
+                return 'treatment'
+
+            default:
+                return 'control'
+        }
+    }
+
     public async listFeatureEvaluations(): Promise<ListFeatureEvaluationsResponse> {
         const request: ListFeatureEvaluationsRequest = {
             userContext: {
@@ -154,12 +173,26 @@ export class FeatureConfigProvider {
                     await vscode.commands.executeCommand('aws.amazonq.refreshStatusBar')
                 }
             }
-            if (Auth.instance.isInternalAmazonUser()) {
+            if (this.getWorkspaceContextGroup() === 'treatment') {
                 // Enable local workspace index by default only once, for Amzn users.
                 const isSet = globals.globalState.get<boolean>('aws.amazonq.workspaceIndexToggleOn') || false
                 if (!isSet) {
                     await CodeWhispererSettings.instance.enableLocalIndex()
                     globals.globalState.tryUpdate('aws.amazonq.workspaceIndexToggleOn', true)
+
+                    await vscode.window
+                        .showInformationMessage(
+                            localize(
+                                'AWS.amazonq.chat.workspacecontext.enable.message',
+                                'Amazon Q: Workspace index is now enabled. You can disable it from Amazon Q settings.'
+                            ),
+                            localize('AWS.amazonq.opensettings', 'Open settings')
+                        )
+                        .then((r) => {
+                            if (r === 'Open settings') {
+                                void Commands.tryExecute('aws.amazonq.configure').then()
+                            }
+                        })
                 }
             }
         } catch (e) {