NPM jasmine-core Package

Jasmine-Core

Overview

Jasmine-Core is a simple framework for writing unit tests in JavaScript. It lets you write tests that self-document and become more readable and maintainable. Jasmine-Core is used for testing both synchronous and asynchronous code.

Installation

npm install --save-dev jasmine-core

Usage

To use Jasmine-Core, you first need to define the test suite and the test cases as shown below:

describe("A suite", function() {
  it("contains spec with an expectation", function() {
    expect(true).toBe(true);
  });
});

describe: defines a test suite. A suite is a collection of related test cases.
it: defines a test case. A test case is a single test that verifies a specific behavior of the code being tested.
expect: asserts the expected outcome of the test.

Configuration Options

Jasmine-Core provides various configuration options to customize the testing environment. These options can be set before running the tests.
jasmine.DEFAULT_TIMEOUT_INTERVAL: Sets the default timeout interval for all asynchronous tests.
jasmine.DEFAULT_UPDATE_INTERVAL: Sets the default interval for updating the test runner UI.
jasmine.getEnv().addReporter: Adds a new reporter to the test runner.
jasmine.getEnv().configure: Configures the test runner with the provided options.

Best Practices

Here are some best practices for writing tests with Jasmine-Core:

  • Keep tests independent: Each test case should be independent of other test cases.
  • Use descriptive names: Use clear and concise names for test suites and test cases.
  • Avoid nesting: Avoid nesting test suites and test cases too deeply.
  • Use spies and mocks: Use spies and mocks to isolate the code being tested from its dependencies.
  • Clean up after each test: Make sure to clean up any resources or state changes made during each test case.

Implementation Guide

To implement Jasmine-Core in your project, follow these steps:

  1. Create a new test file (e.g., spec.js)
  2. Include the Jasmine-Core library:
<script src="jasmine-core.js"></script>
  1. Define your test suites and test cases:
describe("A suite", function() {
  it("contains spec with an expectation", function() {
    expect(true).toBe(true);
  });
});
  1. Run your tests using a test runner like Karma or Mocha:
karma start

Examples

Example 1: Testing a function

describe("A Calculator", function() {
  it("can add two numbers", function() {
    const calculator = new Calculator();
    expect(calculator.add(1, 2)).toBe(3);
  });
});

Example 2: Testing asynchronous code

describe("An asynchronous function", function() {
  it("returns a value after 1 second", function(done) {
    setTimeout(function() {
      done();
    }, 1000);
  });
});

Resources