Three stories about 

 testing 

Marina Miranovich

@obnoxious_mari

http://bit.ly/func2015

2

Table of contents

3

The novel 'About tdd'

4

Intro

5

TDD Pros

TDD can also drive the design of a program (the programmer is concerned with the interface before the implementation);

6

TDD Pros

The lower coupling between objects (CBO).

7

TDD Pros

The total code implementation time could be shorter (and TDD cuts the costs);

8

TDD Cost Profit

9

Cost of defect

10

chapter 1. legacy code

11

legacy code 'features'

• Spaghetti-code;
• Different technologies and approaches;
• JS not ready for testing.

12

legacy code advice

Don't write every new piece of code without tests

13

chapter 2. have no time for testing

14

hot projects

• Hackathon;
• Proof of concept;
• Your example...

15

have no time for tests. advice

Keep calm and write tests

16

chapter 3. want but can't

17

want but can't. advice

writing tests is a habit

18

Happy end

• Sometimes you need some arguments;
• It's never too late;
• Make tests your habit;
• Don't give up.

19

The Story 'About Unit testing''

20

intro. Unit testing

 What?  Individual units of source code.

 Why?  Are tested to determine whether they are fit for use.

21

anti-patterns

• Not isolated test context;
• Complex mocking;
• Testing to much at once.

22

it becomes better

  it('get series', function () {
    $httpBackend.expectGET('http://server/series');
    createShowInfoController();
    $scope.getSeries();
    $httpBackend.flush();

    console.log('$scope.series shouldn't be empty');
    except($scope.series.length).beGreaterThan(0);
  });
            

23

test fails

  > showInfoController get series FAILED
  >    Expect 0 to be greater than 0.
  >      at Object...
            

24

'not good enough test' markers

• console.log()
• try {...} catch {...}

25

console.log > custom matcher

  beforeEach(function() {
      this.addMatchers({
          toNotEmptyArray: function() {
              this.message = function() {
                  return "Expected " + this.actual + " to be not empty";
              };
              return this.actual.length > 0;
          }
      });
  });
            

26

try/catch > expect error

  expect(fn).toThrow(Error);
            

27

hmmm...

  describe('#getSeries', function () {
    it('should have function called getSeries', function () {...});
  });
  
  describe('when $scope.series.length is 0', function () {
    it('should set $scope.isEmptyResult to true', function () {...});
    it('should call showDefaultMessage', function () {...});
  });

            

just unit test

 
  describe('seriesController', function () {

    it('should init controller', function () {...});
    it('should get series', function () {...});

    describe('empty result', function () {
      it('should configure module with defaults', function () {...});
    });
  });

29

Happy end

anti-patterns

• Not isolated test context;
• Complex mocking;
• Testing to much at once.

'not good enough test' markers

• console.log()
• try {...} catch {...}

30

The anecdote 'just About testing'

31

testing mind map

32

by testing layer

 

33

by targets

 

34

happy end

35

Thank you!