fix: strenghen NEP trigger conditions (#2438)

## Problem
Bring the code we removed previously back https://github.com/aws/language-servers/pull/2424/files#diff-10a12088df160c3eec8bb5eedd826e4ee475614c9b3a544fa2393cdeed92bc24L231-L238 and make the trigger criteria more strict.


1. Non empty right context starting next line
2. Recent edits in the past 20 seconds
3. Classifier result is greater than the threshold

## Solution

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## License

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

Author: Will-ShaoHua

server/aws-lsp-codewhisperer/src/language-server/inline-completion/auto-trigger/editPredictionAutoTrigger.ts

@@ -221,7 +221,7 @@ export class EditClassifier {
         this.features = this.prepareFeatures(params)
     }
 
-    shouldTriggerNep(): { shouldTrigger: boolean; threshold: number; score: number } {
+    shouldTriggerEdits(): { shouldTrigger: boolean; threshold: number; score: number } {
         const s = this.score()
         return {
             score: s,

server/aws-lsp-codewhisperer/src/language-server/inline-completion/handler/editCompletionHandler.test.ts

@@ -345,7 +345,7 @@ describe('EditCompletionHandler', () => {
 
         function aTriggerStub(flag: boolean): EditAutotrigger.EditClassifier {
             return {
-                shouldTriggerNep: sinon
+                shouldTriggerEdits: sinon
                     .stub()
                     .returns({ score: 0, threshold: EditAutotrigger.EditClassifier.THRESHOLD, shouldTrigger: flag }),
             } as any as EditAutotrigger.EditClassifier
@@ -354,6 +354,9 @@ describe('EditCompletionHandler', () => {
         it('should return empty result when shouldTriggerEdits returns false', async () => {
             workspace.getWorkspaceFolder.returns(undefined)
 
+            const shouldTriggerEditsStub = sinon
+                .stub(require('../utils/triggerUtils'), 'shouldTriggerEdits')
+                .returns(false)
             sinon.stub(EditAutotrigger, 'EditClassifier').returns(aTriggerStub(false))
 
             const result = await handler._invoke(
@@ -366,12 +369,16 @@ describe('EditCompletionHandler', () => {
             )
 
             assert.deepEqual(result, EMPTY_RESULT)
+            shouldTriggerEditsStub.restore()
         })
 
         it('should create session and call generateSuggestions when trigger is valid', async () => {
             workspace.getWorkspaceFolder.returns(undefined)
 
             sinon.stub(EditAutotrigger, 'EditClassifier').returns(aTriggerStub(true))
+            const shouldTriggerEditsStub = sinon
+                .stub(require('../utils/triggerUtils'), 'shouldTriggerEdits')
+                .returns(true)
             codeWhispererService.constructSupplementalContext.resolves(null)
             codeWhispererService.generateSuggestions.resolves({
                 suggestions: [{ itemId: 'item-1', content: 'test content' }],
@@ -389,6 +396,8 @@ describe('EditCompletionHandler', () => {
 
             assert.strictEqual(result.items.length, 1)
             sinon.assert.called(codeWhispererService.generateSuggestions)
+
+            shouldTriggerEditsStub.restore()
         })
 
         it('should handle active session and emit telemetry', async () => {
@@ -399,6 +408,9 @@ describe('EditCompletionHandler', () => {
             if (currentSession) {
                 sessionManager.activateSession(currentSession)
             }
+            const shouldTriggerEditsStub = sinon
+                .stub(require('../utils/triggerUtils'), 'shouldTriggerEdits')
+                .returns(true)
             sinon.stub(EditAutotrigger, 'EditClassifier').returns(aTriggerStub(true))
             codeWhispererService.constructSupplementalContext.resolves(null)
             codeWhispererService.generateSuggestions.resolves({
@@ -416,11 +428,16 @@ describe('EditCompletionHandler', () => {
             )
 
             assert.strictEqual(currentSession?.state, 'DISCARD')
+
+            shouldTriggerEditsStub.restore()
         })
 
         it('should handle supplemental context when available', async () => {
             workspace.getWorkspaceFolder.returns(undefined)
 
+            const shouldTriggerEditsStub = sinon
+                .stub(require('../utils/triggerUtils'), 'shouldTriggerEdits')
+                .returns(true)
             sinon.stub(EditAutotrigger, 'EditClassifier').returns(aTriggerStub(true))
             codeWhispererService.constructSupplementalContext.resolves({
                 items: [{ content: 'context', filePath: 'file.ts' }],
@@ -441,6 +458,8 @@ describe('EditCompletionHandler', () => {
             )
 
             sinon.assert.calledWith(codeWhispererService.generateSuggestions, sinon.match.has('supplementalContexts'))
+
+            shouldTriggerEditsStub.restore()
         })
     })
 

server/aws-lsp-codewhisperer/src/language-server/inline-completion/handler/editCompletionHandler.ts

@@ -22,7 +22,7 @@ import { CodeWhispererSession, SessionManager } from '../session/sessionManager'
 import { CursorTracker } from '../tracker/cursorTracker'
 import { CodewhispererLanguage, getSupportedLanguageId } from '../../../shared/languageDetection'
 import { WorkspaceFolderManager } from '../../workspaceContext/workspaceFolderManager'
-import { inferTriggerChar } from '../utils/triggerUtils'
+import { inferTriggerChar, shouldTriggerEdits } from '../utils/triggerUtils'
 import {
     emitEmptyUserTriggerDecisionTelemetry,
     emitServiceInvocationFailure,
@@ -212,6 +212,8 @@ export class EditCompletionHandler {
         const workspaceId = workspaceState?.webSocketClient?.isConnected() ? workspaceState.workspaceId : undefined
 
         const recentEdits = await this.recentEditsTracker.generateEditBasedContext(textDocument)
+
+        // TODO: Refactor and merge these 2 shouldTrigger into single one
         const classifier = new EditClassifier(
             {
                 fileContext: fileContextClss,
@@ -221,10 +223,22 @@ export class EditCompletionHandler {
             },
             this.logging
         )
+        const classifierBasedTrigger = classifier.shouldTriggerEdits()
+
+        const ruleBasedTrigger = shouldTriggerEdits(
+            this.codeWhispererService,
+            fileContextClss.toServiceModel(),
+            params,
+            this.cursorTracker,
+            this.recentEditsTracker,
+            this.sessionManager,
+            true
+        )
 
-        const qEditsTrigger = classifier.shouldTriggerNep()
+        // Both classifier and rule based conditions need to evaluate to true otherwise we wont fire Edits requests
+        const shouldFire = classifierBasedTrigger.shouldTrigger && ruleBasedTrigger !== undefined
 
-        if (!qEditsTrigger.shouldTrigger) {
+        if (!shouldFire) {
             return EMPTY_RESULT
         }