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JavaScript Testing with Jasmine
book

JavaScript Testing with Jasmine

by Evan Hahn
March 2013
Intermediate to advanced
52 pages
51m
English
O'Reilly Media, Inc.
Content preview from JavaScript Testing with Jasmine

Chapter 8. Reference

Jasmine on the Web

The Basic Structure of a Suite

  describe("colors", function() {
      describe("red", function() {
          var red;
          beforeEach(function() {
              red = new Color("red");
          });
          afterEach(function() {
              red = null;
          });
          it("has the correct value", function() {
              expect(red.hex).toEqual("FF0000");
          });
          it("makes orange when mixed with yellow", function() {
              var yellow = new Color("yellow");
              var orange = new Color("orange");
              expect(red.mix(yellow)).toEqual(orange);
          });
      });
  });

Matchers Reference

  • toEqual checks for equality, not necessarily the same object.
  • toBe checks if two objects are the same.
  • toBeTruthy checks if a value is truthy (not just true).
  • toBeFalsy checks if a value is falsy (not just false).
  • toContain checks if a value is inside another.
  • toBeDefined checks if a value is defined.
  • toBeUndefined checks if a value is undefined.
  • toBeNull checks if a value is null.
  • toBeNaN checks if a value is NaN.
  • toBeCloseTo checks decimal proximity.
  • toMatch checks if a value matches a given regular expression.
  • toThrow checks if a function throws an error.
  • .not inverts the meaning of the following matcher.

List of Falsy Values

  • false
  • 0
  • ""
  • undefined (note that the variable undefined isn’t always undefined!)
  • null
  • NaN

Reserved Words in Jasmine

The following are words that you shouldn’t use in your code so that you don’t cause conflicts with Jasmine:

  • jasmine (and everything in its namespace)
  • describe
  • it
  • expect
  • beforeEach
  • afterEach
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Publisher Resources

ISBN: 9781449356729Errata Page