Audit and trim @azure-tools/typespec-ts emitter dependencies (#4754)

Fixes #4537.

This PR audits the `@azure-tools/typespec-ts` emitter's dependencies and
removes/replaces several that were unmaintained, redundant, or only
powering dead code paths.

## Dependency changes
- **Removed `handlebars`** (runtime dep) — replaced the four metadata
builders with a tiny in-house `renderTemplate` (a mustache subset
supporting `{{var}}` and `{{#if}}/{{else}}/{{/if}}` with handlebars
standalone-whitespace semantics). Output was verified byte-identical
against handlebars across a boolean matrix.
- **Removed `mkdirp`** (devDep) — the only usage (`mkdirp -p coverage`)
is now a portable `node -e
"require('fs').mkdirSync('coverage',{recursive:true})"`.
- **Removed redundant `prettier`** from `devDependencies` (it was
already in `dependencies`).
- **Replaced unmaintained `npm-run-all`** with `concurrently` (already
in the repo catalog, actively maintained). `npm-run-all` had no release
since 2018. Mapped `--race` to `concurrently --kill-others --success
first` and verified the exit-code/teardown semantics.
- Dropped `handlebars`, `mkdirp`, and `npm-run-all` from the workspace
catalog.

## Cleanup enabled by the audit
- **Removed dead README template paths**: `karmaConfig`,
`nonBrandedReadmeTemplate`, and `serviceDocURL` were unused; the README
template now treats the `@azure` scope as always-on (every generated
package is branded), dropping the `{{#if azure}}` gates.
- **Removed the internal `is-typespec-test` emitter option** — its only
effect was gating the README "Install the package" section. Cleaned up
the option schema, interface, transform, docs, regenerated reference
docs, and 79 test `tspconfig.yaml` fixtures.

## Merge
- Merged latest `main` (including #4750's coverage/spector unification);
resolved the one `package.json` scripts conflict.

## Verification
Replicated the `Consistency` CI gates locally: `format:check`, package
`lint`, `cspell`, `chronus verify`, and `deps check` (catalog-sync) all
pass. Build, `test-next`, and `unit-test` suites are green.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

---------

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: xirzec

.chronus/changes/typespec-ts-dependency-audit-2026-6-29-14-40-0.md

@@ -0,0 +1,7 @@
+---
+changeKind: internal
+packages:
+  - "@azure-tools/typespec-ts"
+---
+
+Remove unused `handlebars` and `mkdirp` dependencies. README, snippets, sample-test, and recorded-client metadata files now use a small built-in template renderer instead of Handlebars, and the test-server scripts create the coverage directory with Node instead of `mkdirp`. Also drop dead metadata templates (`karmaConfig`, the non-branded README template) that were no longer emitted.

.chronus/changes/typespec-ts-remove-is-typespec-test-2026-6-29-17-0-0.md

@@ -0,0 +1,7 @@
+---
+changeKind: internal
+packages:
+  - "@azure-tools/typespec-ts"
+---
+
+Remove the internal `is-typespec-test` emitter option. Its only effect was hiding the README "Install the package" section for test packages, so the install section is now always emitted and the option (and the `isReleasablePackage` metadata it gated) has been dropped.

packages/typespec-ts/CONTRIBUTING.md

@@ -84,7 +84,6 @@ pnpm check:tree        # fails if regeneration left the git tree dirty
        emitter-output-dir: "{project-root}"
        generate-metadata: true
        generate-test: false
-       is-typespec-test: true
        hierarchy-client: false
        package-details:
          name: "@msinternal/auth-apikey"

packages/typespec-ts/README.md

@@ -126,12 +126,6 @@ other cases:
 
 Whether to generate sample files, for basic samples of your generated sdks. Defaults to `undefined`. Management packages' default to `true`.
 
-### `is-typespec-test`
-
-**Type:** `boolean`
-
-Internal option for test
-
 ### `azure-arm`
 
 **Type:** `boolean`

packages/typespec-ts/package.json

@@ -23,11 +23,11 @@
     "lint": "eslint . --ext .ts --max-warnings=0",
     "lint:fix": "eslint . --fix --ext .ts",
     "check:tree": "node ./test/commands/check-clean-tree.ts",
-    "integration-test-ci": "npm-run-all copy:typespec spector-test",
-    "spector-test": "npm-run-all --silent -p start-test-server --race generate-and-run",
-    "start-test-server": "mkdirp -p coverage && npx tsp-spector serve ./node_modules/@azure-tools/azure-http-specs/specs ./node_modules/@typespec/http-specs/specs --port 3002  --coverageFile ./coverage/spector-coverage-typescript-azure.json",
+    "integration-test-ci": "npm run copy:typespec && npm run spector-test",
+    "spector-test": "concurrently --kill-others --success first \"npm:start-test-server\" \"npm:generate-and-run\"",
+    "start-test-server": "node ./test/commands/start-test-server.js",
     "copy:typespec": "node ./test/commands/copy-typespec.ts",
-    "generate-and-run": "npm run generate-tsp-only:client && npm-run-all -p integration-test:alone generate-tsp-only:declarations && npm run stop-test-server -- -p 3002",
+    "generate-and-run": "npm run generate-tsp-only:client && concurrently --kill-others-on-fail \"npm:integration-test:alone\" \"npm:generate-tsp-only:declarations\" && npm run stop-test-server -- -p 3002",
     "generate-tsp-only": "node ./test/commands/gen-spector.js",
     "generate-tsp-only:client": "node ./test/commands/gen-spector.js --phase=client",
     "generate-tsp-only:declarations": "node ./test/commands/gen-spector.js --phase=declarations",
@@ -66,9 +66,7 @@
     "@typespec/xml": "workspace:^",
     "@typespec/ts-http-runtime": "catalog:",
     "cross-env": "catalog:",
-    "mkdirp": "catalog:",
-    "npm-run-all": "catalog:",
-    "prettier": "catalog:",
+    "concurrently": "catalog:",
     "vitest": "catalog:",
     "vite": "catalog:",
     "@vitest/coverage-v8": "catalog:",
@@ -86,7 +84,6 @@
   },
   "dependencies": {
     "fast-xml-parser": "catalog:",
-    "handlebars": "catalog:",
     "prettier": "catalog:",
     "ts-morph": "catalog:",
     "tslib": "catalog:"

packages/typespec-ts/src/interfaces.ts

@@ -223,7 +223,6 @@ export interface ClientOptions {
   generateTest?: boolean;
   generateSample?: boolean;
   azureOutputDirectory?: string;
-  isTypeSpecTest?: boolean;
   serviceInfo?: ServiceInfo;
   azureArm?: boolean;
   enableOperationGroup?: boolean;

packages/typespec-ts/src/lib.ts

@@ -39,7 +39,6 @@ export interface EmitterOptions {
    */
   "generate-test"?: boolean;
   "generate-sample"?: boolean;
-  "is-typespec-test"?: boolean;
   "azure-arm"?: boolean;
   "enable-operation-group"?: boolean;
   "enable-model-namespace"?: boolean;
@@ -170,11 +169,6 @@ export const EmitterOptionsSchema: JSONSchemaType<EmitterOptions> = {
       description:
         "Whether to generate sample files, for basic samples of your generated sdks. Defaults to `undefined`. Management packages' default to `true`.",
     },
-    "is-typespec-test": {
-      type: "boolean",
-      nullable: true,
-      description: "Internal option for test",
-    },
     "azure-arm": {
       type: "boolean",
       nullable: true,

packages/typespec-ts/src/metadata/build-readme-file.ts

@@ -1,12 +1,10 @@
 // Copyright (c) Microsoft Corporation.
 // Licensed under the MIT License.
 
-// eslint-disable-next-line @typescript-eslint/ban-ts-comment
-// @ts-ignore: to fix the handlebars issue
-import hbs from "handlebars";
 import { ClientModel } from "../interfaces.js";
 import { getClientName } from "../utils/name-constructors.js";
 import { NameType, normalizeName } from "../utils/name-utils.js";
+import { renderTemplate } from "./render-template.js";
 
 const azureReadmeModularTemplate = `# {{ clientDescriptiveName }} library for JavaScript
 
@@ -38,23 +36,18 @@ Key links:
 
 See our [support policy](https://github.com/Azure/azure-sdk-for-js/blob/main/SUPPORT.md) for more details.
 
-{{#if azure}}
 ### Prerequisites
 
 - An [Azure subscription][azure_sub].
-{{/if}}
 
-{{#if isReleasablePackage}}
 ### Install the \`{{ clientPackageName }}\` package
 
 Install the {{ clientDescriptiveName }} library for JavaScript with \`npm\`:
 
 \`\`\`bash
 npm install {{ clientPackageName }}
 \`\`\`
-{{/if}}
 
-{{#if azure}}
 {{#if addCredentials}}
 ### Create and authenticate a \`{{ clientClassName}}\`
 
@@ -129,7 +122,8 @@ const credential = new InteractiveBrowserCredential({
 const client = new {{ clientClassName }}("<endpoint>", credential);
 \`\`\`
 {{/if}}
-{{/if}}{{/if}}
+{{/if}}
+
 
 ### JavaScript Bundle
 To use this client library in the browser, first you need to use a bundler. For details on how to do this, please refer to our [bundling documentation](https://aka.ms/AzureSDKBundling).
@@ -140,7 +134,6 @@ To use this client library in the browser, first you need to use a bundler. For
 
 \`{{ clientClassName }}\` is the primary interface for developers using the {{ clientDescriptiveName }} library. Explore the methods on this client object to understand the different features of the {{ serviceName }} service that you can access.
 
-{{#if azure}}
 ## Troubleshooting
 
 ### Logging
@@ -153,7 +146,7 @@ import { setLogLevel } from "@azure/logger";
 setLogLevel("info");
 \`\`\`
 
-For more detailed instructions on how to enable logs, you can look at the [@azure/logger package docs]({{ repoURL }}/tree/main/sdk/core/logger).
+For more detailed instructions on how to enable logs, you can look at the [@azure/logger package docs](https://github.com/Azure/azure-sdk-for-js/tree/main/sdk/core/logger).
 
 {{#if samplesURL}}
 ## Next steps
@@ -163,54 +156,16 @@ Please take a look at the [samples]({{ samplesURL }}) directory for detailed exa
 
 ## Contributing
 
-If you'd like to contribute to this library, please read the [contributing guide]({{ contributingGuideURL }}) to learn more about how to build and test the code.
+If you'd like to contribute to this library, please read the [contributing guide](https://github.com/Azure/azure-sdk-for-js/blob/main/CONTRIBUTING.md) to learn more about how to build and test the code.
 
 ## Related projects
 
-- [{{ projectName }}]({{ repoURL }})
+- [Microsoft Azure SDK for JavaScript](https://github.com/Azure/azure-sdk-for-js)
 
 [azure_sub]: https://azure.microsoft.com/free/
 [azure_portal]: https://portal.azure.com
-{{#if identityPackageURL}}[azure_identity]: {{ identityPackageURL }}
-{{/if}}[defaultazurecredential]: {{ identityPackageURL }}#defaultazurecredential
-{{/if}}
-`;
-
-const nonBrandedReadmeTemplate = `# {{ clientDescriptiveName }} library for JavaScript
-
-{{ description }}
-
-Key links:
-
-{{#if packageSourceURL}}
-- [Source code]({{ packageSourceURL }})
-{{/if}}
-{{#if packageNPMURL}}
-- [Package (NPM)]({{ packageNPMURL }})
-{{/if}}
-{{#if apiRefURL}}
-- [API reference documentation]({{ apiRefURL }})
-{{/if}}
-{{#if serviceDocURL}}
-- [Product documentation]({{ serviceDocURL }})
-{{/if}}
-{{#if samplesURL}}
-- [Samples]({{ samplesURL }})
-{{/if}}
-
-## Getting started
-
-### Currently supported environments
-
-- LTS versions of Node.js
-
-### Install the \`{{ clientPackageName }}\` package
-
-Install the {{ clientDescriptiveName }} library for JavaScript with \`npm\`:
-
-\`\`\`bash
-npm install {{ clientPackageName }}
-\`\`\`
+[azure_identity]: https://github.com/Azure/azure-sdk-for-js/tree/main/sdk/identity/identity
+[defaultazurecredential]: https://github.com/Azure/azure-sdk-for-js/tree/main/sdk/identity/identity#defaultazurecredential
 `;
 
 const apiReferenceTemplate = `{{#if apiRefURL}}
@@ -228,8 +183,6 @@ interface Metadata {
   clientPackageName: string;
   /** The name of the client class */
   clientClassName: string;
-  /** The URL of the repository the package lives in */
-  repoURL?: string;
   /** The URL to the package directory in the repository */
   packageSourceURL?: string;
   /** The URL to the package's samples */
@@ -240,29 +193,12 @@ interface Metadata {
   description?: string;
   /** The URL to the package on npmjs.org */
   packageNPMURL?: string;
-  /** The name of the project that lives in the repository */
-  projectName?: string;
   /** whether the client accepts standard credentials */
   addCredentials?: boolean;
-  /** The link to the identity package in the repository */
-  identityPackageURL?: string;
-  /** The URL for the service document */
-  serviceDocURL?: string;
-  /** The dependency info for this service */
-  dependencyDescription?: string;
-  dependencyLink?: string;
-  /** Indicates if the package is a multi-client */
-  hasMultiClients?: boolean;
   /** The URL to the API reference */
   apiRefURL?: string;
   /** Check if the rp is management plane */
   azureArm?: boolean;
-  /** Whether the package being generated is for an Azure service */
-  azure: boolean;
-  /** Indicates if the package is a test/releasable package. */
-  isReleasablePackage?: boolean;
-  /** The link to the contributing guide in the repository */
-  contributingGuideURL?: string;
   /** Indicates if the package need generate test files */
   generateTest?: boolean;
   /** Indicates if the package need SubscriptionId as the client parameter */
@@ -271,13 +207,10 @@ interface Metadata {
 
 export function buildReadmeFile(model: ClientModel) {
   const metadata = createMetadata(model) ?? {};
-  const readmeFileContents = hbs.compile(
-    model.options ? azureReadmeModularTemplate : nonBrandedReadmeTemplate,
-    { noEscape: true },
-  );
+  const content = renderTemplate(azureReadmeModularTemplate, metadata as Record<string, unknown>);
   return {
     path: "README.md",
-    content: readmeFileContents(metadata),
+    content,
   };
 }
 
@@ -301,7 +234,10 @@ export function updateReadmeFile(
   try {
     const metadata = createMetadata(model) ?? {};
 
-    const newApiRefLink = hbs.compile(apiReferenceTemplate, { noEscape: true })(metadata).trim();
+    const newApiRefLink = renderTemplate(
+      apiReferenceTemplate,
+      metadata as Record<string, unknown>,
+    ).trim();
 
     if (!newApiRefLink) {
       return { path: "README.md", content: existingReadmeContent };
@@ -329,14 +265,12 @@ function createMetadata(model: ClientModel): Metadata | undefined {
     return;
   }
   // const packageDetails = model.options.packageDetails;
-  const { packageDetails, azureOutputDirectory, serviceInfo, isTypeSpecTest } = model.options;
+  const { packageDetails, azureOutputDirectory, serviceInfo } = model.options;
 
-  const azureHuh =
-    packageDetails?.scopeName === "azure" || packageDetails?.scopeName === "azure-rest";
   const repoURL = "https://github.com/Azure/azure-sdk-for-js";
   const relativePackageSourcePath = azureOutputDirectory;
   const packageSourceURL =
-    relativePackageSourcePath && repoURL && `${repoURL}/tree/main/${relativePackageSourcePath}`;
+    relativePackageSourcePath && `${repoURL}/tree/main/${relativePackageSourcePath}`;
 
   const clientPackageName = packageDetails?.name;
   const clientClassName = getClientName(model);
@@ -363,17 +297,9 @@ function createMetadata(model: ClientModel): Metadata | undefined {
     packageNPMURL: `https://www.npmjs.com/package/${clientPackageName}`,
     samplesURL:
       model.options.generateSample && packageSourceURL ? `${packageSourceURL}/samples` : undefined,
-    apiRefURL: azureHuh
-      ? `https://learn.microsoft.com/javascript/api/${clientPackageName}${apiRefUrlQueryParameter}`
-      : undefined,
+    apiRefURL: `https://learn.microsoft.com/javascript/api/${clientPackageName}${apiRefUrlQueryParameter}`,
     azureArm: Boolean(model.options.azureArm),
-    azure: azureHuh,
-    isReleasablePackage: !isTypeSpecTest,
-    repoURL: repoURL,
-    projectName: azureHuh ? "Microsoft Azure SDK for JavaScript" : undefined,
-    identityPackageURL: repoURL && `${repoURL}/tree/main/sdk/identity/identity`,
     addCredentials: model.options.addCredentials,
-    contributingGuideURL: repoURL && `${repoURL}/blob/main/CONTRIBUTING.md`,
     generateTest: model.options.generateTest,
     hasSubscriptionId: model.options.hasSubscriptionId,
   };