refactor(amazonq): revert pre-fetch next recommendations for inline completion (#6567)

This reverts commit 50c9121.

## Problem
In the previous change, we applied prefect to every responses. However,
this introduced issues with inline completion, causing it to behave
inconsistently and produce unexpected completions in the next response.

## Solution
To mitigate this, this PR rolls back the responses prefect change to
restore stable inline completion behavior.

---

- Treat all work as PUBLIC. Private `feature/x` branches will not be
squash-merged at release time.
- Your code changes must meet the guidelines in
[CONTRIBUTING.md](https://github.com/aws/aws-toolkit-vscode/blob/master/CONTRIBUTING.md#guidelines).
- License: I confirm that my contribution is made under the terms of the
Apache 2.0 license.

Author: evanliu048

packages/amazonq/.changes/next-release/Removal-319fc7c8-22e0-44f1-a636-2f4040689b32.json

@@ -0,0 +1,4 @@
+{
+	"type": "Removal",
+	"description": "Reverted prefetch logic to enable more stable inline completion"
+}

packages/amazonq/test/unit/codewhisperer/commands/onAcceptance.test.ts

@@ -9,21 +9,19 @@ import * as sinon from 'sinon'
 import {
     onAcceptance,
     AcceptedSuggestionEntry,
-    CodeWhispererSessionState,
+    session,
     CodeWhispererTracker,
     RecommendationHandler,
     AuthUtil,
-    CodeWhispererSession,
 } from 'aws-core-vscode/codewhisperer'
 import { resetCodeWhispererGlobalVariables, createMockTextEditor } from 'aws-core-vscode/test'
 import { assertTelemetryCurried } from 'aws-core-vscode/test'
 
 describe('onAcceptance', function () {
-    let session: CodeWhispererSession
     describe('onAcceptance', function () {
         beforeEach(async function () {
-            session = CodeWhispererSessionState.instance.getSession()
             await resetCodeWhispererGlobalVariables()
+            session.reset()
         })
 
         afterEach(function () {

packages/amazonq/test/unit/codewhisperer/commands/onInlineAcceptance.test.ts

@@ -8,22 +8,15 @@ import * as vscode from 'vscode'
 import * as sinon from 'sinon'
 import { resetCodeWhispererGlobalVariables, createMockTextEditor } from 'aws-core-vscode/test'
 import { assertTelemetryCurried } from 'aws-core-vscode/test'
-import {
-    onInlineAcceptance,
-    RecommendationHandler,
-    AuthUtil,
-    CodeWhispererSessionState,
-    CodeWhispererSession,
-} from 'aws-core-vscode/codewhisperer'
+import { onInlineAcceptance, RecommendationHandler, AuthUtil, session } from 'aws-core-vscode/codewhisperer'
 import { globals } from 'aws-core-vscode/shared'
 import { extensionVersion } from 'aws-core-vscode/shared'
 
 describe('onInlineAcceptance', function () {
-    let session: CodeWhispererSession
     describe('onInlineAcceptance', function () {
         beforeEach(async function () {
-            session = CodeWhispererSessionState.instance.getSession()
             await resetCodeWhispererGlobalVariables()
+            session.reset()
         })
 
         afterEach(function () {

packages/amazonq/test/unit/codewhisperer/service/completionProvider.test.ts

@@ -12,7 +12,7 @@ import {
     getLabel,
     Recommendation,
     RecommendationHandler,
-    CodeWhispererSessionState,
+    session,
 } from 'aws-core-vscode/codewhisperer'
 import { createMockDocument, resetCodeWhispererGlobalVariables } from 'aws-core-vscode/test'
 
@@ -39,7 +39,6 @@ describe('completionProviderService', function () {
 
     describe('getCompletionItem', function () {
         it('should return targetCompletionItem given input', function () {
-            const session = CodeWhispererSessionState.instance.getSession()
             session.startPos = new vscode.Position(0, 0)
             RecommendationHandler.instance.requestId = 'mock_requestId_getCompletionItem'
             session.sessionId = 'mock_sessionId_getCompletionItem'
@@ -96,7 +95,6 @@ describe('completionProviderService', function () {
 
     describe('getCompletionItems', function () {
         it('should return completion items for each non-empty recommendation', async function () {
-            const session = CodeWhispererSessionState.instance.getSession()
             session.recommendations = [
                 { content: "\n\t\tconsole.log('Hello world!');\n\t}" },
                 { content: '\nvar a = 10' },
@@ -108,7 +106,6 @@ describe('completionProviderService', function () {
         })
 
         it('should return empty completion items when recommendation is empty', async function () {
-            const session = CodeWhispererSessionState.instance.getSession()
             session.recommendations = []
             const mockPosition = new vscode.Position(14, 83)
             const mockDocument = createMockDocument()

packages/amazonq/test/unit/codewhisperer/service/inlineCompletionService.test.ts

@@ -14,7 +14,7 @@ import {
     CodeSuggestionsState,
     ConfigurationEntry,
     CWInlineCompletionItemProvider,
-    CodeWhispererSessionState,
+    session,
     AuthUtil,
     listCodeWhispererCommandsId,
     DefaultCodeWhispererClient,
@@ -46,7 +46,6 @@ describe('inlineCompletionService', function () {
         })
 
         it('should call checkAndResetCancellationTokens before showing inline and next token to be null', async function () {
-            const session = CodeWhispererSessionState.instance.getSession()
             const mockEditor = createMockTextEditor()
             sinon.stub(RecommendationHandler.instance, 'getRecommendations').resolves({
                 result: 'Succeeded',
@@ -71,7 +70,6 @@ describe('inlineCompletionService', function () {
 
     describe('clearInlineCompletionStates', function () {
         it('should remove inline reference and recommendations', async function () {
-            const session = CodeWhispererSessionState.instance.getSession()
             const fakeReferences = [
                 {
                     message: '',

packages/amazonq/test/unit/codewhisperer/service/recommendationHandler.test.ts

@@ -8,7 +8,7 @@ import * as vscode from 'vscode'
 import * as sinon from 'sinon'
 import {
     ReferenceInlineProvider,
-    CodeWhispererSessionState,
+    session,
     AuthUtil,
     DefaultCodeWhispererClient,
     RecommendationsList,
@@ -55,7 +55,6 @@ describe('recommendationHandler', function () {
         })
 
         it('should assign correct recommendations given input', async function () {
-            const session = CodeWhispererSessionState.instance.getSession()
             assert.strictEqual(CodeWhispererCodeCoverageTracker.instances.size, 0)
             assert.strictEqual(
                 CodeWhispererCodeCoverageTracker.getTracker(mockEditor.document.languageId)?.serviceInvocationCount,
@@ -75,7 +74,7 @@ describe('recommendationHandler', function () {
             }
             const handler = new RecommendationHandler()
             sinon.stub(handler, 'getServerResponse').resolves(mockServerResult)
-            await handler.getRecommendations(mockClient, mockEditor, 'AutoTrigger', config, session, 'Enter', false)
+            await handler.getRecommendations(mockClient, mockEditor, 'AutoTrigger', config, 'Enter', false)
             const actual = session.recommendations
             const expected: RecommendationsList = [{ content: "print('Hello World!')" }, { content: '' }]
             assert.deepStrictEqual(actual, expected)
@@ -86,7 +85,6 @@ describe('recommendationHandler', function () {
         })
 
         it('should assign request id correctly', async function () {
-            const session = CodeWhispererSessionState.instance.getSession()
             const mockServerResult = {
                 recommendations: [{ content: "print('Hello World!')" }, { content: '' }],
                 $response: {
@@ -101,7 +99,7 @@ describe('recommendationHandler', function () {
             const handler = new RecommendationHandler()
             sinon.stub(handler, 'getServerResponse').resolves(mockServerResult)
             sinon.stub(handler, 'isCancellationRequested').returns(false)
-            await handler.getRecommendations(mockClient, mockEditor, 'AutoTrigger', config, session, 'Enter', false)
+            await handler.getRecommendations(mockClient, mockEditor, 'AutoTrigger', config, 'Enter', false)
             assert.strictEqual(handler.requestId, 'test_request')
             assert.strictEqual(session.sessionId, 'test_request')
             assert.strictEqual(session.triggerType, 'AutoTrigger')
@@ -130,10 +128,9 @@ describe('recommendationHandler', function () {
                 strategy: 'empty',
             })
             sinon.stub(performance, 'now').returns(0.0)
-            const session = CodeWhispererSessionState.instance.getSession()
             session.startPos = new vscode.Position(1, 0)
             session.startCursorOffset = 2
-            await handler.getRecommendations(mockClient, mockEditor, 'AutoTrigger', config, session, 'Enter')
+            await handler.getRecommendations(mockClient, mockEditor, 'AutoTrigger', config, 'Enter')
             const assertTelemetry = assertTelemetryCurried('codewhisperer_serviceInvocation')
             assertTelemetry({
                 codewhispererRequestId: 'test_request',
@@ -170,11 +167,10 @@ describe('recommendationHandler', function () {
             const handler = new RecommendationHandler()
             sinon.stub(handler, 'getServerResponse').resolves(mockServerResult)
             sinon.stub(performance, 'now').returns(0.0)
-            const session = CodeWhispererSessionState.instance.getSession()
             session.startPos = new vscode.Position(1, 0)
             session.requestIdList = ['test_request_empty']
             session.startCursorOffset = 2
-            await handler.getRecommendations(mockClient, mockEditor, 'AutoTrigger', config, session, 'Enter')
+            await handler.getRecommendations(mockClient, mockEditor, 'AutoTrigger', config, 'Enter')
             const assertTelemetry = assertTelemetryCurried('codewhisperer_userDecision')
             assertTelemetry({
                 codewhispererRequestId: 'test_request_empty',
@@ -196,7 +192,6 @@ describe('recommendationHandler', function () {
             sinon.restore()
         })
         it('should return true if any response is not empty', function () {
-            const session = CodeWhispererSessionState.instance.getSession()
             const handler = new RecommendationHandler()
             session.recommendations = [
                 {
@@ -209,14 +204,12 @@ describe('recommendationHandler', function () {
         })
 
         it('should return false if response is empty', function () {
-            const session = CodeWhispererSessionState.instance.getSession()
             const handler = new RecommendationHandler()
             session.recommendations = []
             assert.ok(!handler.isValidResponse())
         })
 
         it('should return false if all response has no string length', function () {
-            const session = CodeWhispererSessionState.instance.getSession()
             const handler = new RecommendationHandler()
             session.recommendations = [{ content: '' }, { content: '' }]
             assert.ok(!handler.isValidResponse())
@@ -229,7 +222,6 @@ describe('recommendationHandler', function () {
         })
 
         it('should set the completion type to block given a multi-line suggestion', function () {
-            const session = CodeWhispererSessionState.instance.getSession()
             session.setCompletionType(0, { content: 'test\n\n   \t\r\nanother test' })
             assert.strictEqual(session.getCompletionType(0), 'Block')
 
@@ -241,7 +233,6 @@ describe('recommendationHandler', function () {
         })
 
         it('should set the completion type to line given a single-line suggestion', function () {
-            const session = CodeWhispererSessionState.instance.getSession()
             session.setCompletionType(0, { content: 'test' })
             assert.strictEqual(session.getCompletionType(0), 'Line')
 
@@ -250,7 +241,6 @@ describe('recommendationHandler', function () {
         })
 
         it('should set the completion type to line given a multi-line completion but only one-lien of non-blank sequence', function () {
-            const session = CodeWhispererSessionState.instance.getSession()
             session.setCompletionType(0, { content: 'test\n\t' })
             assert.strictEqual(session.getCompletionType(0), 'Line')
 
@@ -267,7 +257,6 @@ describe('recommendationHandler', function () {
 
     describe('on event change', async function () {
         beforeEach(function () {
-            const session = CodeWhispererSessionState.instance.getSession()
             const fakeReferences = [
                 {
                     message: '',
@@ -285,14 +274,12 @@ describe('recommendationHandler', function () {
         })
 
         it('should remove inline reference onEditorChange', async function () {
-            const session = CodeWhispererSessionState.instance.getSession()
             session.sessionId = 'aSessionId'
             RecommendationHandler.instance.requestId = 'aRequestId'
             await RecommendationHandler.instance.onEditorChange()
             assert.strictEqual(ReferenceInlineProvider.instance.refs.length, 0)
         })
         it('should remove inline reference onFocusChange', async function () {
-            const session = CodeWhispererSessionState.instance.getSession()
             session.sessionId = 'aSessionId'
             RecommendationHandler.instance.requestId = 'aRequestId'
             await RecommendationHandler.instance.onFocusChange()

packages/amazonq/test/unit/codewhisperer/service/telemetry.test.ts

@@ -22,7 +22,7 @@ import {
     invokeRecommendation,
     ConfigurationEntry,
     RecommendationHandler,
-    CodeWhispererSessionState,
+    session,
     vsCodeCursorUpdateDelay,
     AuthUtil,
 } from 'aws-core-vscode/codewhisperer'
@@ -36,7 +36,6 @@ type CodeWhispererResponse = ListRecommendationsResponse & {
 let tempFolder: string
 
 describe.skip('CodeWhisperer telemetry', async function () {
-    const session = CodeWhispererSessionState.instance.getSession()
     let sandbox: sinon.SinonSandbox
     let client: DefaultCodeWhispererClient
 
@@ -520,7 +519,6 @@ async function manualTrigger(
 
 // Note: RecommendationHandler.isSuggestionVisible seems not to work well, hence not using it
 async function waitUntilSuggestionSeen(index: number = 0) {
-    const session = CodeWhispererSessionState.instance.getSession()
     const state = await waitUntil(
         async () => {
             const r = session.getSuggestionState(index)

packages/amazonq/test/unit/codewhisperer/util/telemetryHelper.test.ts

@@ -5,7 +5,7 @@
 
 import assert from 'assert'
 import { assertTelemetryCurried, resetCodeWhispererGlobalVariables } from 'aws-core-vscode/test'
-import { TelemetryHelper, Completion, CodeWhispererSessionState } from 'aws-core-vscode/codewhisperer'
+import { TelemetryHelper, Completion, session } from 'aws-core-vscode/codewhisperer'
 import {
     CodewhispererCompletionType,
     CodewhispererSuggestionState,
@@ -39,7 +39,6 @@ function aCompletion(): Completion {
 }
 
 describe('telemetryHelper', function () {
-    const session = CodeWhispererSessionState.instance.getSession()
     describe('clientComponentLatency', function () {
         let sut: TelemetryHelper
 
@@ -49,7 +48,6 @@ describe('telemetryHelper', function () {
 
         afterEach(function () {
             sinon.restore()
-            session.reset()
         })
 
         it('resetClientComponentLatencyTime should reset state variables', function () {

packages/core/src/codewhisperer/client/codewhisperer.ts

@@ -17,7 +17,7 @@ import { isSsoConnection } from '../../auth/connection'
 import { pageableToCollection } from '../../shared/utilities/collectionUtils'
 import apiConfig = require('./service-2.json')
 import userApiConfig = require('./user-service-2.json')
-import { CodeWhispererSessionState } from '../util/codeWhispererSession'
+import { session } from '../util/codeWhispererSession'
 import { getLogger } from '../../shared/logger/logger'
 import { indent } from '../../shared/utilities/textUtilities'
 import { keepAliveHeader } from './agent'
@@ -133,7 +133,6 @@ export class DefaultCodeWhispererClient {
     }
 
     async createUserSdkClient(maxRetries?: number): Promise<CodeWhispererUserClient> {
-        const session = CodeWhispererSessionState.instance.getSession()
         const isOptedOut = CodeWhispererSettings.instance.isOptoutEnabled()
         session.setFetchCredentialStart()
         const bearerToken = await AuthUtil.instance.getBearerToken()

packages/core/src/codewhisperer/commands/invokeRecommendation.ts

@@ -8,7 +8,7 @@ import { vsCodeState, ConfigurationEntry } from '../models/model'
 import { resetIntelliSenseState } from '../util/globalStateUtil'
 import { DefaultCodeWhispererClient } from '../client/codewhisperer'
 import { RecommendationHandler } from '../service/recommendationHandler'
-import { CodeWhispererSessionState } from '../util/codeWhispererSession'
+import { session } from '../util/codeWhispererSession'
 import { RecommendationService } from '../service/recommendationService'
 
 /**
@@ -33,7 +33,6 @@ export async function invokeRecommendation(
     /**
      * When using intelliSense, if invocation position changed, reject previous active recommendations
      */
-    const session = CodeWhispererSessionState.instance.getSession()
     if (vsCodeState.isIntelliSenseActive && editor.selection.active !== session.startPos) {
         resetIntelliSenseState(
             config.isManualTriggerEnabled,