test-scenarios

Easily run the same unit test with different test data.

Not tied to a specific library, it can be used with

• mocha
• jasmine
• jest
• any library where tests are defined within a function.

Example

// sum.js
export const sum = (a, b) => a + b;

// sum.test.js
import scenarios from "test-scenarios";

describe("sum", () => {
  scenarios([
    { a: 1, b: 2, result: 3 },
    { a: -1, b: 1, result: 0 }
  ], ({ a, b, result }, testIndex) => {
    describe(`When ${a} and ${b} are passed`, () => {
      it(`should return ${result}`, () => {
        expect(sum(a, b)).toEqual(result);
      });
    });
  });
});

API

scenarios(testScenarios, testsFn)

• testScenarios: any contains the test data for every scenario.
• testsFn: Function the tests to run each time with different data, it can contain a whole describe block or multiple it/test. The function will be invoked with the data for the scenario and the test index.

Note for Jest users

You can achieve the same result as the above by using the following syntax:

describe.each([
  { a: 1, b: 2, result: 3 },
  { a: -1, b: 1, result: 0 }
])('sum', ({ a, b, result }) => {
  describe(`When ${a} and ${b} are passed`, () => {
    it(`should return ${result}`, () => {
      expect(sum(a, b)).toEqual(result);
    });
  });
});

More info on describe.each and test.each.