karma-typescript

library5.5.4jsnpmunverified

karma-typescript is a Karma plugin designed to simplify running unit tests for TypeScript projects. It seamlessly integrates TypeScript compilation, type checking, and test execution within the Karma test runner without requiring separate build steps. It also provides remapped test coverage reports via Istanbul, ensuring accurate coverage data even after transpilation. The current stable version is 5.5.4, with recent releases focusing on bug fixes and compatibility updates for newer versions of Karma and TypeScript. Its key differentiators include built-in type checking, automatic source map generation for debugging, and robust remapped coverage reporting, making it a comprehensive solution for testing TypeScript code.

testing

npm install karma-typescript

github ↗package ↗

INSTALL

IMPORT

SIG · KARMA-TYPESCRIPT

karma-typescript

testingjavascriptv5.5.4

Install

—

Import

—

Disk

—

Pass rate

0/ 6

Env Coverage0 / 6

glibc

18–22

musl

18–22

Install & Compatibility

Where this runs

tested against v? · npm install

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

node 18–226 runs

build_error

glibc

node 18–226 runs

build_error

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

framework

✓ config.set({ frameworks: ["jasmine", "karma-typescript"], // ... });

✗ require('karma-typescript')

karma-typescript is configured as a framework and preprocessor, not imported directly into application code. Ensure 'karma-typescript' is included in the `frameworks` array in `karma.conf.js`.

preprocessor

✓ config.set({ preprocessors: { "**/*.ts": "karma-typescript" // or '*.tsx' for React }, // ... });

✗ preprocessors: { '**/*.ts': require('karma-typescript') }

Configure karma-typescript as a preprocessor for your TypeScript files in `karma.conf.js`. This tells Karma to compile TypeScript files before tests run.

reporter

✓ config.set({ reporters: ["progress", "karma-typescript"], // ... });

✗ reporters: ["karma-typescript-reporter"]

To enable the specialized TypeScript reporter and coverage features, include 'karma-typescript' in the `reporters` array in `karma.conf.js`.

This configuration sets up Karma with Jasmine and karma-typescript to compile and run tests on TypeScript files located in the 'src' directory, producing remapped coverage reports.

module.exports = function(config) { config.set({ basePath: './', frameworks: ["jasmine", "karma-typescript"], files: [ "src/**/*.ts" // Use '*.tsx' for React projects ], preprocessors: { "**/*.ts": "karma-typescript" // Use '*.tsx' for React projects }, reporters: ["progress", "karma-typescript"], browsers: ["ChromeHeadless"], // Use ChromeHeadless for CI environments karmaTypescript: { compilerOptions: { esModuleInterop: true, module: "CommonJS", target: "ES5" }, include: ["src/**/*.ts"], exclude: ["node_modules"] } }); };

Debug

Known issues

breakingkarma-typescript versions 5.x require Karma 5.x or 6.x. Earlier versions of Karma may not be fully supported, leading to unexpected behavior or compilation issues.

fix

Upgrade Karma to a compatible version (e.g., `npm install karma@^6 --save-dev`) and ensure `typescript` peer dependency is met. Refer to the `peerDependencies` section for exact ranges.

affects: >=5.0.0

gotchaVersion 5.3.0 of karma-typescript was noted as 'messed up' by the maintainer and was quickly followed by 5.4.0. Users on 5.3.0 might encounter unresolved bugs that were fixed in 5.4.0.

fix

Ensure you are using `karma-typescript@5.4.0` or higher to avoid issues present in version 5.3.0. Always check the latest patch releases for bug fixes.

affects: =5.3.0

gotchaMissing or incompatible `acorn` dependency can cause the test run to lock or fail. This has been a recurring bug fix in recent patch versions.

fix

Upgrade to `karma-typescript@5.5.2` or newer to ensure the correct `acorn` dependency is available and avoid test run lockups. If issues persist, try `npm install acorn` explicitly.

affects: <5.5.2

gotchaWhen `singleRun` is set to `false`, karma-typescript might still kill the process if coverage thresholds aren't met. This behavior can be unexpected during watch mode.

fix

Update to `karma-typescript@5.4.0` or newer, which includes a fix to prevent the process from being killed when coverage thresholds aren't met in `singleRun: false` mode.

affects: <5.4.0

Errors

Common errors & fixes

Error: Cannot find module 'acorn'

A dependency issue where the 'acorn' package, used for parsing, is not correctly resolved or installed.

fix

Upgrade `karma-typescript` to the latest patch release (e.g., `npm install karma-typescript@latest --save-dev`) or explicitly install `acorn`: `npm install acorn --save-dev`.

TypeError: Cannot read property 'karmaTypescript' of undefined

The `karma-typescript` plugin is not correctly recognized or initialized by Karma, often due to missing `frameworks` entry.

fix

Ensure `karma-typescript` is listed in the `frameworks` array in your `karma.conf.js`: `frameworks: ["jasmine", "karma-typescript"],`

Coverage threshold not met, exiting with error code 1.

The configured code coverage percentage was not reached by the tests, causing the process to terminate. This is a deliberate feature.

fix

Adjust the coverage thresholds in your `karma.conf.js` under `karmaTypescript.coverageOptions.threshold`, or set `karmaTypescript.coverageOptions.failOnThresholdNotMet: false` if you do not want failures on unmet thresholds.

TSxxxx: [TypeScript error message]

A TypeScript compilation error occurred during the test run, indicating issues in your source or test files.

fix

Review the accompanying TypeScript error message and fix the code. Ensure your `tsconfig.json` or `karmaTypescript.compilerOptions` are correctly configured for your project.

Upgrade

Version history

5.5.4latest on npm

Audit

Dependencies

karmarequiredRequired peer dependency as karma-typescript is a plugin for Karma. Supports Karma versions 1 through 6.

typescriptrequiredRequired peer dependency for TypeScript compilation and type checking. Supports TypeScript versions 1 through 5.

Agent activity

2 hits · last 30 days

node

Resources

githubhttps://github.com/monounity/karma-typescript ↗

packagehttps://www.npmjs.com/package/karma-typescript ↗