lint: set prettier arrowParens=always

Problem:
javascript arrow functions allow braces `{ ... }` to surround an
expression without a `return`, which leads to bugs such as
aws#3659
aws#3662

Example:

    return supplementalContexts.filter(item => { item.content.trim().length !== 0 })

should be:

    return supplementalContexts.filter(item => item.content.trim().length !== 0)

Solution:
- Set prettier `arrowParens=always`. This is the default, explained
  here: https://prettier.io/docs/en/options.html#arrow-function-parentheses
  > At first glance, avoiding parentheses may look like a better choice
  because of less visual noise. However, when Prettier removes
  parentheses, it becomes harder to add type annotations, extra
  arguments or default values as well as making other changes.
  Consistent use of parentheses provides a better developer experience
  when editing real codebases, which justifies the default value for the
  option.
- Note: this is equivalent to the eslint `@stylistic/no-confusing-arrow` rule.
  - https://eslint.style/packages/default#stylistic-eslint-plugin
  - https://eslint.style/rules/default/no-confusing-arrow

Author: justinmk3

package.json

@@ -16,7 +16,7 @@
         "singleQuote": true,
         "semi": false,
         "bracketSpacing": true,
-        "arrowParens": "avoid",
+        "arrowParens": "always",
         "endOfLine": "lf"
     },
     "scripts": {

packages/amazonq/scripts/build/copyFiles.ts

@@ -26,7 +26,7 @@ interface CopyTask {
 }
 
 const tasks: CopyTask[] = [
-    ...['LICENSE', 'NOTICE'].map(f => {
+    ...['LICENSE', 'NOTICE'].map((f) => {
         return { target: path.join('../../', f), destination: path.join(projectRoot, f) }
     }),
 

packages/amazonq/scripts/build/syncPackageJson.ts

@@ -25,7 +25,7 @@ function main() {
     const coreLibPackageJson = JSON.parse(fs.readFileSync(coreLibPackageJsonFile, { encoding: 'utf-8' }))
 
     const coreSettings = coreLibPackageJson.contributes.configuration.properties
-    Object.keys(coreSettings).forEach(key => {
+    Object.keys(coreSettings).forEach((key) => {
         if (key.startsWith('amazonQ')) {
             packageJson.contributes.configuration.properties[key] = coreSettings[key]
         }

packages/amazonq/src/extensionCommon.ts

@@ -44,7 +44,7 @@ export const amazonQContextPrefix = 'amazonq'
  */
 export async function activateAmazonQCommon(context: vscode.ExtensionContext, isWeb: boolean) {
     initialize(context, isWeb)
-    const homeDirLogs = await fs.init(context, homeDir => {
+    const homeDirLogs = await fs.init(context, (homeDir) => {
         void messages.showViewLogsMessage(`Invalid home directory (check $HOME): "${homeDir}"`)
     })
     errors.init(fs.getUsername(), env.isAutomation())
@@ -73,12 +73,12 @@ export async function activateAmazonQCommon(context: vscode.ExtensionContext, is
                                 } and older. Your AWS Toolkit was updated to version 3.0 or later.`,
                                 'Reload Now'
                             )
-                            .then(async resp => {
+                            .then(async (resp) => {
                                 if (resp === 'Reload Now') {
                                     await vscode.commands.executeCommand('workbench.action.reloadWindow')
                                 }
                             }),
-                    reason => {
+                    (reason) => {
                         getLogger().error('workbench.extensions.installExtension failed: %O', reason)
                     }
                 )

packages/amazonq/test/e2e/amazonq/featureDev.test.ts

@@ -78,14 +78,14 @@ describe('Amazon Q Feature Dev', function () {
 
     function waitForButtons(buttons: FollowUpTypes[]) {
         return tab.waitForEvent(() => {
-            return buttons.every(value => tab.hasButton(value))
+            return buttons.every((value) => tab.hasButton(value))
         })
     }
 
     async function waitForText(text: string) {
         await tab.waitForEvent(
             () => {
-                return tab.getChatItems().some(chatItem => chatItem.body === text)
+                return tab.getChatItems().some((chatItem) => chatItem.body === text)
             },
             {
                 waitIntervalInMs: 250,

packages/amazonq/test/e2e/amazonq/framework/framework.ts

@@ -62,7 +62,7 @@ export class qTestingFramework {
          * This implements the VSCode -> Mynah UI flow
          */
         this.disposables.push(
-            DefaultAmazonQAppInitContext.instance.getAppsToWebViewMessageListener().onMessage(async message => {
+            DefaultAmazonQAppInitContext.instance.getAppsToWebViewMessageListener().onMessage(async (message) => {
                 // Emulate the json format of postMessage
                 const event = {
                     data: JSON.stringify(message),

packages/amazonq/test/e2e/amazonq/framework/jsdomInjector.ts

@@ -28,5 +28,5 @@ export function injectJSDOM() {
     })
 
     // jsdom doesn't have support for structuredClone. See https://github.com/jsdom/jsdom/issues/3363
-    global.structuredClone = val => JSON.parse(JSON.stringify(val))
+    global.structuredClone = (val) => JSON.parse(JSON.stringify(val))
 }

packages/amazonq/test/e2e/amazonq/framework/messenger.ts

@@ -51,7 +51,7 @@ export class Messenger {
         }
 
         const lastChatItem = this.getChatItems().pop()
-        const option = lastChatItem?.followUp?.options?.filter(option => option.type === type)
+        const option = lastChatItem?.followUp?.options?.filter((option) => option.type === type)
         if (!option || option.length > 1) {
             assert.fail('Could not find follow up option')
         }
@@ -61,9 +61,9 @@ export class Messenger {
 
     findCommand(command: string) {
         return this.getCommands()
-            .map(groups => groups.commands)
+            .map((groups) => groups.commands)
             .flat()
-            .filter(commands => commands.command === command)
+            .filter((commands) => commands.command === command)
     }
 
     getCommands() {
@@ -82,7 +82,7 @@ export class Messenger {
         return (
             this.getChatItems()
                 .pop()
-                ?.followUp?.options?.map(opt => opt.type)
+                ?.followUp?.options?.map((opt) => opt.type)
                 .includes(type) ?? false
         )
     }

packages/amazonq/test/e2e/amazonq/framework/text.ts

@@ -22,7 +22,7 @@ export function verifyTextOrder(chatItems: ChatItem[], expectedText: RegExp[]) {
     }
 
     if (currInd !== expectedText.length) {
-        const chatItemBodies = chatItems.filter(item => item !== undefined).map(item => item.body)
+        const chatItemBodies = chatItems.filter((item) => item !== undefined).map((item) => item.body)
         const expected = expectedText.join(', ')
         assert.fail(`Items did not appear in expected order. Found ${chatItemBodies} but expected ${expected}`)
     }

packages/amazonq/test/unit/amazonqGumby/transformFileHandler.test.ts

@@ -45,9 +45,8 @@ describe('Amazon Q Transform - transformFileHandler tests', function () {
                 </dependencies>
                 </DependencyUpdatesReport>
                 `
-            const { latestVersion, majorVersions, minorVersions, status } = await parseVersionsListFromPomFile(
-                testXmlReport
-            )
+            const { latestVersion, majorVersions, minorVersions, status } =
+                await parseVersionsListFromPomFile(testXmlReport)
 
             assert.strictEqual(latestVersion, '1.18.32')
             assert.strictEqual(minorVersions[0], '0.12.0')