TypeScript Testing Library

Get started

npm i -D @osmoscraft/node-testing-library

Create run-test.ts in your project root with the following content:

import { getTests, runTests } from "@osmoscraft/node-testing-library";

async function run() {
  const tests = await getTests("src", /\.test\.ts$/);
  runTests(tests);
}

run();

Update package.json with the following scripts to run tests

  "scripts": {
    "test": "ts-node-dev --quiet --transpile-only run-test.ts",
    "test:watch": "ts-node-dev --respawn --watch --transpile-only run-test.ts",
  },

Write your first test in src/hello-world.test.ts

import { describe, expect, it } from "@osmoscraft/node-testing-library";

describe("hello world", () => {
  it("should pass", async () => {
    await expect("hello").toEqual("hello");
  });
});

Please make sure to use await in frontend of each expect or the error reporting may not be able to surface all failed tests

TypeScript configuration

This library relies on ts-node-dev to compile TypeScript to JavavScript only the fly. Since the JavaScript output will be executed in a Node.js environment, your tsconfig.json should produce code that is compatible with Node.js. If your existing tsconfig.json produces code using ESNext module, you will need to specific a separate tsconfig.test.json like this:

{
  "compilerOptions": {
    "target": "es2019",
    "moduleResolution": "node",
    "module": "CommonJS",
    "importsNotUsedAsValues": "error",
    "strict": true,
    "esModuleInterop": true,
    "outDir": "dist"
  }
}

and consume it in your package.json test script:

  "scripts": {
    "test": "ts-node-dev --project tsconfig.test.json --quiet --transpile-only run-test.ts",
    "test:watch": "ts-node-dev --project tsconfig.test.json --respawn --watch --transpile-only run-test.ts",
  },