@waqas385/nestjs-testgen

NestJS e2e testing CLI — generate Jest and Supertest endpoint tests from controllers and DTOs, with optional wiring of test:e2e, Jest config, and npm scripts. Use this when you want API / HTTP integration tests or automated test scaffolding for a TypeScript NestJS backend.

Related searches: NestJS test generator, generate NestJS e2e tests, Jest e2e NestJS, Supertest scaffold, DTO-based API tests.

What it does

This package scans a NestJS project for controller classes, discovers routes and body DTOs, and generates a scaffolded .spec.ts file with request templates and example payloads.

It is intended for projects where DTOs are properly defined and the NestJS controllers use decorator metadata such as @Controller, @Get, @Post, @Patch, and @Body().

Usage

1. Install in your NestJS project:

npm install --save-dev @waqas385/nestjs-testgen

2. Generate and auto-setup tests for your NestJS project:

npx @waqas385/nestjs-testgen --project . --output test --test-file generated.e2e-spec.ts --overwrite

Quick start in one block:

npm i -D @waqas385/nestjs-testgen
npx @waqas385/nestjs-testgen --project . --output test --test-file generated.e2e-spec.ts --overwrite
npm run test:e2e:generated

This command now does all of the following by default:

• Generates the e2e test file.
• Detects missing test setup and initializes it (after confirmation prompt).
• Adds missing test scripts in package.json (test, test:watch, test:cov, test:e2e, test:e2e:generated).
• Adds a generator script in package.json: test:generate.
• Adds default jest config in package.json if missing.
• Adds @waqas385/nestjs-testgen to target project devDependencies if missing.
• Updates Jest e2e config (test/jest-e2e.json or the --config path from test:e2e script) with:
  • "moduleNameMapper": { "^src/(.*)$": "<rootDir>/../src/$1" }
• Adds/updates test:e2e:generated in the target project's package.json.
• Writes generated tests to <output>/<test-file> (for example: test/generated.e2e-spec.ts).

3. Run generated tests:

npm run test:e2e:generated

To regenerate from inside the target project later:

npm run test:generate

4. Optional: include dependency installation and immediate test execution:

npx @waqas385/nestjs-testgen --project . --output test --test-file generated.e2e-spec.ts --overwrite --install-test-deps --run-generated-tests

If you want to skip prompts and auto-approve setup changes, add --yes. If you want to preview all changes without modifying files, add --dry-run. If you need machine-readable output for CI, add --json.

FAQ

How do I generate NestJS e2e tests with Jest and Supertest?

Install @waqas385/nestjs-testgen, then run npx @waqas385/nestjs-testgen with --project, --output, and --test-file. See the Usage section and --install-test-deps if your project is missing test dependencies.

Is this for unit tests or end-to-end (e2e) tests?

It targets e2e / integration-style HTTP tests against your Nest app (Supertest + Jest), not isolated unit tests of single functions.

Why does Bundlephobia show a build error?

This is a Node.js CLI; browser bundlers fail on built-ins like fs and path. See Bundlephobia note.

How do I run the CLI in CI?

Use --yes to skip prompts and optionally --json for machine-readable output. See the CI examples in Example.

CLI Options

• --project <path>: NestJS project root (default: .)
• --output <path>: Output directory for generated tests (default: generated-tests)
• --controllers <glob>: Controller glob pattern (default: src/**/*.controller.ts)
• --test-file <name>: Output file name (default: generated.e2e-spec.ts)
• --overwrite: Overwrite existing generated test file
• --no-setup: Skip Jest/package.json auto-setup changes
• --install-test-deps: Install missing e2e test dependencies in target project
• --run-generated-tests: Run npm run test:e2e:generated after generation
• --yes: Auto-approve setup/init changes when project test config is missing
• --dry-run: Preview generated/updated files, scripts, config, deps, and test run command without writing anything
• --json: Print machine-readable JSON result (and JSON errors)

Example

npx @waqas385/nestjs-testgen --project . --output test --test-file generated.e2e-spec.ts --overwrite --install-test-deps --run-generated-tests

Dry run preview:

npx @waqas385/nestjs-testgen --project . --output test --test-file generated.e2e-spec.ts --overwrite --install-test-deps --run-generated-tests --dry-run

CI-friendly preview:

npx @waqas385/nestjs-testgen --project . --output test --test-file generated.e2e-spec.ts --overwrite --dry-run --yes --json

CI-friendly apply:

npx @waqas385/nestjs-testgen --project . --output test --test-file generated.e2e-spec.ts --overwrite --install-test-deps --yes --json

Run via npm script (optional):

{
  "scripts": {
    "nestjs-testgen": "nestjs-testgen"
  }
}

Then:

npm run nestjs-testgen -- --project . --output test --test-file generated.e2e-spec.ts --overwrite

Cross-platform support

• Works on Linux, macOS, and Windows.
• Generated npm scripts and Jest paths use forward slashes for compatibility.
• Uses Node APIs (path, fs) for file handling rather than shell-specific path logic.
• For non-interactive environments (CI), use --yes to bypass prompts.

Bundlephobia note

• This package is a Node.js CLI tool for NestJS projects and is not intended for browser bundling.
• Bundlephobia may report a build error because it attempts a browser-focused bundle and this package uses Node built-ins like fs, path, readline, and child_process.
• Use npm install, npm run build, and CLI execution in a Node environment as the source of truth for package health.

Notes

• The package uses ts-morph to analyze TypeScript AST and extract route and DTO metadata.
• Generated payload values are best-effort examples and may need manual adjustment for application-specific business logic.

Discoverability and migration

• Package name: @waqas385/nestjs-testgen
• CLI command: nestjs-testgen
• If you used older package names, migrate with:

npm uninstall nest-testgen
npm i -D @waqas385/nestjs-testgen

Deprecated legacy package (if you published it): point users to this package with npm deprecate <old-name> "Use @waqas385/nestjs-testgen" after you publish the replacement.

Repository: github.com/waqas385/nest-testgen.

Support

If you run into problems while configuring or running this package, feel free to reach out by email at [email protected].