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Test Suite

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An extension of Deno’s built-in test runner to add setup/teardown hooks and make it easier to organize tests in a format similar to Jasmine, Jest, and Mocha.

Features

  • Ability to group tests together into test suites
  • Setup/teardown hooks for test suites (beforeAll, afterAll, beforeEach, afterEach)
  • Tests within a test suite inherit configuration options
  • describe/it functions similar to Jasmine, Jest, and Mocha
  • shorthand for focusing and ignoring tests

Installation

To include this module in a Deno project, you can import directly from the TS files. This module is available in Deno’s third part module registry but can also be imported directly from GitHub using raw content URLs.

// Import from Deno's third party module registry
import { describe, it } from "https://deno.land/x/test_suite@0.10.1/mod.ts";
// Import from GitHub
import { describe, it } "https://raw.githubusercontent.com/udibo/test_suite/0.10.1/mod.ts";

Usage

When you have a set of tests that are related, you can group them together by creating a test suite. A test suite can contain other test suites and tests. All tests within a suite will inherit their options from the suite unless they specifically set them.

The beforeAll and afterAll hook options can be used to do something before and after all the tests in the suite run. If you would like to set values for all tests within the suite, you can create a context interface that defines all the values available to the tests that are defined in the beforeAll function.

The beforeEach and afterEach hook options are similar to beforeAll and afterAll except they are called before and after each individual test.

Below are some examples of how to use describe and it in tests.

See deno docs for more information.

Nested test grouping

The example below can be found here.

import {
  afterEach,
  beforeEach,
  describe,
  it,
} from "https://deno.land/x/test_suite@0.10.1/mod.ts";
import { assertEquals } from "https://deno.land/std@0.126.0/testing/asserts.ts";
import {
  getUser,
  resetUsers,
  User,
} from "https://deno.land/x/test_suite@0.10.1/examples/user.ts";

describe("user describe", () => {
  let user: User;

  beforeEach(() => {
    user = new User("Kyle June");
  });

  afterEach(() => {
    resetUsers();
  });

  it("create", () => {
    const user = new User("John Doe");
    assertEquals(user.name, "John Doe");
  });

  describe("getUser", () => {
    it("user does not exist", () => {
      assertEquals(getUser("John Doe"), undefined);
    });

    it("user exists", () => {
      assertEquals(getUser("Kyle June"), user);
    });
  });

  it("resetUsers", () => {
    assertEquals(getUser("Kyle June"), user);
    resetUsers();
    assertEquals(getUser("Kyle June"), undefined);
  });
});

If you run the above tests using deno test, you will get the following output.

$ deno test
running 1 test from file:///examples/user_nested_test.ts
test user describe ...
  test create ... ok (4ms)
  test getUser ...
    test user does not exist ... ok (4ms)
    test user exists ... ok (3ms)
  ok (11ms)
  test resetUsers ... ok (3ms)
ok (24ms)

test result: ok. 1 passed (5 steps); 0 failed; 0 ignored; 0 measured; 0 filtered out (43ms)

Flat test grouping

The example below can be found here.

import { describe, it } from "https://deno.land/x/test_suite@0.10.1/mod.ts";
import { assertEquals } from "https://deno.land/std@0.126.0/testing/asserts.ts";
import {
  getUser,
  resetUsers,
  User,
} from "https://deno.land/x/test_suite@0.10.1/example/user.ts";

interface UserContext {
  user: User;
}

const userSuite = describe({
  name: "user",
  beforeEach(context: UserContext) {
    context.user = new User("Kyle June");
  },
  afterEach() {
    resetUsers();
  },
});

it(userSuite, "create", () => {
  const user = new User("John Doe");
  assertEquals(user.name, "John Doe");
});

interface GetUserContext extends UserContext {
  value?: number;
}

const getUserSuite = describe<GetUserContext>({
  name: "getUser",
  suite: userSuite,
});

it(getUserSuite, "user does not exist", () => {
  assertEquals(getUser("John Doe"), undefined);
});

it(getUserSuite, "user exists", (context: UserContext) => {
  assertEquals(getUser("Kyle June"), context.user);
});

it(userSuite, "resetUsers", (context: UserContext) => {
  assertEquals(getUser("Kyle June"), context.user);
  resetUsers();
  assertEquals(getUser("Kyle June"), undefined);
});

If you run the above tests using deno test, you will get the following output.

$ deno test
running 1 test from file:///examples/user_flat_test.ts
test user ...
  test create ... ok (3ms)
  test getUser ...
    test user does not exist ... ok (2ms)
    test user exists ... ok (4ms)
  ok (11ms)
  test resetUsers ... ok (3ms)
ok (22ms)

test result: ok. 1 passed (5 steps); 0 failed; 0 ignored; 0 measured; 0 filtered out (44ms)

Shorthand for focusing and ignoring tests

To avoid having to change your test function arguments to be able to focus or ignore tests temporarily, a shorthand has been implemented. This makes it as easy as typing .only and .ignore to focus and ignore tests.

  • To focus a test case, replace it with it.only.
  • To ignore a test case, replace it with it.ignore.
  • To focus a test suite, replace describe with describe.only.
  • To ignore a test suite, replace describe with describe.ignore.

Migrating from earlier versions

The TestSuite class has been turned into an internal only class. To create a test suite, use the describe function instead of creating a new instance of TestSuite directly.

The test function has been removed. Replace test calls with calls to it.

The each function that was previously available has been temporarily removed to allow me to switch over to the test step api quicker. I plan on implementing this later. If you make use of the each function for generating test cases, do not upgrade beyond version 0.9.5.

License

MIT