Slide 1
Slide 1 text
TESTS SHOULD TELL A STORY
LARACON US 2016
Slide 2
Slide 2 text
STORIES
Slide 3
Slide 3 text
WHO KNOWS THIS MAN?
Slide 4
Slide 4 text
FRED ROGERS
Slide 5
Slide 5 text
THE NEIGHBORHOOD LIVES ON
Slide 6
Slide 6 text
We live in a world in which
we need to share
responsibility.
It's easy to say, “It's not my
child, not my community,
not my world, not my
problem.”
Then there are those who
see the need and respond. I
consider those people my
heroes.
Fred Rogers
Slide 7
Slide 7 text
TAYLOR OTWELL
Slide 8
Slide 8 text
No content
Slide 9
Slide 9 text
No content
Slide 10
Slide 10 text
No content
Slide 11
Slide 11 text
No content
Slide 12
Slide 12 text
YOUR CODE
TELLS A STORY
Slide 13
Slide 13 text
No content
Slide 14
Slide 14 text
TESTS SHOULD TELL A STORY
DISTILLED SHARED KNOWLEDGE
▸ Good naming
▸ Good abstractions
▸ Details pushed down
▸ Intent clearly expressed
▸ Test driven (mostly)
Slide 15
Slide 15 text
TESTS SHOULD TELL A STORY
IN STORY FORM
▸ Who are the characters? (Subject & Collaborators)
▸ What is the setting? (Environment)
▸ What is the plot? (Goal of our system)
▸ What is the conflict? (Task at hand)
▸ What is the resolution? (Solution)
Slide 16
Slide 16 text
STORIES ARE NOT JUST TOLD
THEY ARE INTERPRETED
Slide 17
Slide 17 text
I NEED MAYO
Coheed and Cambria
HEADSHOT KID DISASTER FROM SECOND STAGE TURBINE BLADE
Slide 18
Slide 18 text
WHAT DO YOU SEE?
Slide 19
Slide 19 text
No content
Slide 20
Slide 20 text
EVEN FUTURE-YOU WILL
INTERPRET CODE DIFFERENTLY
Slide 21
Slide 21 text
TESTS SHOULD TELL A STORY
COMMUNICATIVE CONCERNS TO CONSIDER
▸ Skill level
▸ Ambiguous intent
▸ Cultural differences
▸ Language differences
▸ Contextual differences
▸ Mood at the time of reading
▸ Knowledge of area/domain of code
Slide 22
Slide 22 text
No content
Slide 23
Slide 23 text
TESTS SHOULD TELL A STORY
EXPECTATIONS
▸ Ex: A method named read in a CSV parsing library
▸ Load the entire file into memory into an array
▸ Stream the file, each line as an array
▸ Load the file into a lazily evaluated collection - each row
lazily loaded in an array
Slide 24
Slide 24 text
AMBIGUITY LEAVES ROOM FOR
INTERPRETATION
Slide 25
Slide 25 text
We don’t make
mistakes, we
have happy
accidents.
Bob Ross
Slide 26
Slide 26 text
WE ARE NOT BOB ROSS
Slide 27
Slide 27 text
WE MAKE MISTAKES
Slide 28
Slide 28 text
OUR MISTAKES HAVE
CONSEQUENCES
Slide 29
Slide 29 text
WRITE TESTS
TO PREVENT HAPPY ACCIDENTS
Slide 30
Slide 30 text
YOU DO WRITE TESTS, DON’T YOU?
Slide 31
Slide 31 text
ಠ_ಠ
Slide 32
Slide 32 text
ಠ_ಠ
Slide 33
Slide 33 text
ಠ_ಠ
Slide 34
Slide 34 text
No content
Slide 35
Slide 35 text
KEYNOTE !"
Slide 36
Slide 36 text
No content
Slide 37
Slide 37 text
TESTS
Slide 38
Slide 38 text
ANATOMY OF A TEST
Slide 39
Slide 39 text
TESTS SHOULD TELL A STORY
ANATOMY OF A TEST - FOUR PHASE
▸ Setup environment and preconditions
▸ Exercise the method/system under test
▸ Verify the result
▸ Tear down the environment
Slide 40
Slide 40 text
TESTS SHOULD TELL A STORY
ANATOMY OF A TEST - AAA
▸ Arrange preconditions and input
▸ Act on the object/method/system under test
▸ Assert what you expect the result to be
Slide 41
Slide 41 text
TESTS SHOULD TELL A STORY
ANATOMY OF A TEST - GIVEN-WHEN-THEN
▸ Arrange - Given
▸ Act - When
▸ Assert - Then
Slide 42
Slide 42 text
SETTING A BASELINE
Slide 43
Slide 43 text
TESTS SHOULD TELL A STORY
PHPUNIT
subject = new UserRepository();
$this->name = ‘Machuga’;
$this->subject->save(new User($this->name));
}
public function teardown() {
$this->subject->clear();
}
public function testCanFindAUserByName() {
$user = $this->subject->findByName($this->name);
$this->assertEquals($this->name, $user->name);
}
}
Slide 44
Slide 44 text
XUNIT
Slide 45
Slide 45 text
TESTS SHOULD TELL A STORY
XUNIT - PHPUNIT
subject = new UserRepository();
$this->name = ‘Machuga’;
$this->subject->save(new User($this->name));
}
public function teardown() {
$this->subject->clear();
}
public function testCanFindAUserByName() {
$user = $this->subject->findByName($this->name);
$this->assertEquals($this->name, $user->name);
}
}
Slide 46
Slide 46 text
TESTS SHOULD TELL A STORY
XUNIT - PHPUNIT
subject = new UserRepository();
$this->name = ‘Machuga’;
$this->subject->save(new User($this->name));
}
public function teardown() {
$this->subject->clear();
}
public function testCanFindAUserByName() {
$user = $this->subject->findByName($this->name);
$this->assertEquals($this->name, $user->name);
}
}
Slide 47
Slide 47 text
TESTS SHOULD TELL A STORY
XUNIT - PHPUNIT
subject = new UserRepository();
$this->name = ‘Machuga’;
$this->subject->save(new User($this->name));
}
public function teardown() {
$this->subject->clear();
}
public function testCanFindAUserByName() {
$user = $this->subject->findByName($this->name);
$this->assertEquals($this->name, $user->name);
}
}
Slide 48
Slide 48 text
TESTS SHOULD TELL A STORY
XUNIT - PHPUNIT
subject = new UserRepository();
$this->name = ‘Machuga’;
$this->subject->save(new User($this->name));
}
public function teardown() {
$this->subject->clear();
}
public function testCanFindAUserByName() {
$user = $this->subject->findByName($this->name);
$this->assertEquals($this->name, $user->name);
}
}
Slide 49
Slide 49 text
TESTS SHOULD TELL A STORY
XUNIT - PHPUNIT
subject = new UserRepository();
$this->name = ‘Machuga’;
$this->subject->save(new User($this->name));
}
public function teardown() {
$this->subject->clear();
}
public function testCanFindAUserByName() {
$user = $this->subject->findByName($this->name);
$this->assertEquals($this->name, $user->name);
}
}
Slide 50
Slide 50 text
TESTS SHOULD TELL A STORY
XUNIT - PHPUNIT
subject = new UserRepository();
$this->name = ‘Machuga’;
$this->subject->save(new User($this->name));
}
public function teardown() {
$this->subject->clear();
}
public function testCanFindAUserByName() {
$user = $this->subject->findByName($this->name);
$this->assertEquals($this->name, $user->name);
}
}
Slide 51
Slide 51 text
TESTS SHOULD TELL A STORY
XUNIT - PHPUNIT
subject = new UserRepository();
$this->name = ‘Machuga’;
$this->subject->save(new User($this->name));
}
public function teardown() {
$this->subject->clear();
}
public function testCanFindAUserByName() {
$user = $this->subject->findByName($this->name);
$this->assertEquals($this->name, $user->name);
}
}
Slide 52
Slide 52 text
TESTS SHOULD TELL A STORY
XUNIT - PHPUNIT
subject = new UserRepository();
$this->name = ‘Machuga’;
$this->subject->save(new User($this->name));
}
public function teardown() {
$this->subject->clear();
}
public function testCanFindAUserByName() {
$user = $this->subject->findByName($this->name);
$this->assertEquals($this->name, $user->name);
}
}
Slide 53
Slide 53 text
SPEC/BDD STYLE
Slide 54
Slide 54 text
AT A BASIC LEVEL
VERY SIMILAR
Slide 55
Slide 55 text
TESTS SHOULD TELL A STORY
XUNIT - PHPUNIT
subject = new UserRepository();
$this->name = ‘Machuga’;
$this->subject->save(new User($this->name));
}
public function teardown() {
$this->subject->clear();
}
public function testCanFindAUserByName() {
$user = $this->subject->findByName($this->name);
$this->assertEquals($this->name, $user->name);
}
}
Slide 56
Slide 56 text
TESTS SHOULD TELL A STORY
SPEC/BDD - PHO
subject = new UserRepository();
$this->name = ‘Machuga’;
$this->subject->save(new User($this->name));
});
afterEach(function() {
$this->subject->clear();
});
it(‘can find a user by name’, function() {
$user = $this->subject->findByName($this->name);
expect($user->name)->toEqual($this->name);
});
});
Slide 57
Slide 57 text
TESTS SHOULD TELL A STORY
XUNIT - PHPUNIT
subject = new UserRepository();
$this->name = ‘Machuga’;
$this->subject->save(new User($this->name));
}
public function teardown() {
$this->subject->clear();
}
public function testCanFindAUserByName() {
$user = $this->subject->findByName($this->name);
$this->assertEquals($this->name, $user->name);
}
}
Slide 58
Slide 58 text
TESTS SHOULD TELL A STORY
SPEC/BDD - PHO
subject = new UserRepository();
$this->name = ‘Machuga’;
$this->subject->save(new User($this->name));
});
afterEach(function() {
$this->subject->clear();
});
it(‘can find a user by name’, function() {
$user = $this->subject->findByName($this->name);
expect($user->name)->toEqual($this->name);
});
});
Slide 59
Slide 59 text
TESTS SHOULD TELL A STORY
SPEC/BDD - PHO
subject = new UserRepository();
$this->name = ‘Machuga’;
$this->subject->save(new User($this->name));
});
afterEach(function() {
$this->subject->clear();
});
it(‘can find a user by name’, function() {
$user = $this->subject->findByName($this->name);
expect($user->name)->toEqual($this->name);
});
});
Slide 60
Slide 60 text
TESTS SHOULD TELL A STORY
SPEC/BDD - PHO
subject = new UserRepository();
$this->name = ‘Machuga’;
$this->subject->save(new User($this->name));
});
afterEach(function() {
$this->subject->clear();
});
it(‘can find a user by name’, function() {
$user = $this->subject->findByName($this->name);
expect($user->name)->toEqual($this->name);
});
});
Slide 61
Slide 61 text
TESTS SHOULD TELL A STORY
SPEC/BDD - PHO
subject = new UserRepository();
$this->name = ‘Machuga’;
$this->subject->save(new User($this->name));
});
afterEach(function() {
$this->subject->clear();
});
it(‘can find a user by name’, function() {
$user = $this->subject->findByName($this->name);
expect($user->name)->toEqual($this->name);
});
});
Slide 62
Slide 62 text
TESTS SHOULD TELL A STORY
SPEC/BDD - PHO
subject = new UserRepository();
$this->name = ‘Machuga’;
$this->subject->save(new User($this->name));
});
afterEach(function() {
$this->subject->clear();
});
it(‘can find a user by name’, function() {
$user = $this->subject->findByName($this->name);
expect($user->name)->toEqual($this->name);
});
});
Slide 63
Slide 63 text
TESTS SHOULD TELL A STORY
SPEC/BDD - PHO
subject = new UserRepository();
$this->name = ‘Machuga’;
$this->subject->save(new User($this->name));
});
afterEach(function() {
$this->subject->clear();
});
it(‘can find a user by name’, function() {
$user = $this->subject->findByName($this->name);
expect($user->name)->toEqual($this->name);
});
});
Slide 64
Slide 64 text
TESTS SHOULD TELL A STORY
SPEC/BDD - PHO
subject = new UserRepository();
$this->name = ‘Machuga’;
$this->subject->save(new User($this->name));
});
afterEach(function() {
$this->subject->clear();
});
it(‘can find a user by name’, function() {
$user = $this->subject->findByName($this->name);
expect($user->name)->toEqual($this->name);
});
});
Slide 65
Slide 65 text
TESTS SHOULD TELL A STORY
SPEC/BDD - PHO
subject = new UserRepository();
$this->name = ‘Machuga’;
$this->subject->save(new User($this->name));
});
afterEach(function() {
$this->subject->clear();
});
it(‘can find a user by name’, function() {
$user = $this->subject->findByName($this->name);
expect($user->name)->toEqual($this->name);
});
});
Slide 66
Slide 66 text
TESTS SHOULD TELL A STORY
SPEC/BDD - PHO
subject = new UserRepository();
$this->name = ‘Machuga’;
$this->subject->save(new User($this->name));
});
afterEach(function() {
$this->subject->clear();
});
it(‘can find a user by name’, function() {
$user = $this->subject->findByName($this->name);
expect($user->name)->toEqual($this->name);
});
});
Slide 67
Slide 67 text
TESTS SHOULD TELL A STORY
NESTED CONTEXTS
subject = new UserRepository();
$this->name = ‘Machuga’;
$this->subject->save(new User($this->name));
});
afterEach(function() {
$this->subject->clear();
});
context(‘when finding a user’, function() {
it(‘can find an existing user by name’, function() {
$user = $this->subject->findByName($this->name);
expect($user->name)->toEqual($this->name);
});
it(‘returns null when given an invalid name’, function() {
$user = $this->subject->findByName(‘Santa Claus’);
expect($user)->toEqual(null);
});
});
});
Slide 68
Slide 68 text
TESTS SHOULD TELL A STORY
SPEC OR DOCUMENTATION FORMATTER PRINTS AS
A User Repository
when finding a user
can find an existing user by name
returns null when given an invalid username
Slide 69
Slide 69 text
TESTS SHOULD TELL A STORY
SUBJECTIVE PREFERENCE TO BDD SPECS OVER XUNIT
▸ Generally written out in sentences
▸ Easily mapped to user stories
▸ Easily mapped to acceptance criteria
▸ Easily readable by stakeholders
▸ Allow for contexts to be described easily
▸ Allow for nested contexts
▸ Handles multiple cases well
▸ I work with them day-to-day
Slide 70
Slide 70 text
HOW ARE YOU FEELING
ABOUT THE SPEC DSL?
Slide 71
Slide 71 text
HOW ARE YOU FEELING
ABOUT THE SPEC DSL?
Slide 72
Slide 72 text
SPEC LIBRARIES
WE’LL BE USING
Slide 73
Slide 73 text
SPEC LIBRARIES
WE’LL BE USING
Slide 74
Slide 74 text
JASMINE
&
RSPEC
Slide 75
Slide 75 text
TESTS SHOULD TELL A STORY
JASMINE
describe(‘A User Repository’, function() {
const subject = new UserRepository();
const name = ‘Machuga’;
beforeEach(function() {
subject.save(new User(name));
});
afterEach(function() {
subject.clear();
});
it(‘can find a user by name’, function() {
const user = subject.findByName(name);
expect(user.name).toEqual(name);
});
});
Slide 76
Slide 76 text
TESTS SHOULD TELL A STORY
JASMINE
describe(‘A User Repository’, function() {
const subject = new UserRepository();
const name = ‘Machuga’;
beforeEach(function() {
subject.save(new User(name));
});
afterEach(function() {
subject.clear();
});
it(‘can find a user by name’, function() {
const user = subject.findByName(name);
expect(user.name).toEqual(name);
});
});
const defines a variable
that cannot be redefined
Slide 77
Slide 77 text
TESTS SHOULD TELL A STORY
JASMINE
describe(‘A User Repository’, function() {
const subject = new UserRepository();
const name = ‘Machuga’;
beforeEach(function() {
subject.save(new User(name));
});
afterEach(function() {
subject.clear();
});
it(‘can find a user by name’, function() {
const user = subject.findByName(name);
expect(user.name).toEqual(name);
});
});
dot syntax rather than ->
Slide 78
Slide 78 text
TESTS SHOULD TELL A STORY
JASMINE
describe(‘A User Repository’, function() {
const subject = new UserRepository();
const name = ‘Machuga’;
beforeEach(function() {
subject.save(new User(name));
});
afterEach(function() {
subject.clear();
});
it(‘can find a user by name’, function() {
const user = subject.findByName(name);
expect(user.name).toEqual(name);
});
});
lexical scope for variables
Slide 79
Slide 79 text
TESTS SHOULD TELL A STORY
RSPEC
describe ‘A User Repository’ do
subject { UserRepository.new }
let(:name) { ‘Machuga’ }
before do
subject.save(User.new(name))
end
after do
subject.clear!
end
it ‘can find a user by name’ do
user = subject.find_by_name(name)
expect(user.name).to eq(name)
end
end
Slide 80
Slide 80 text
TESTS SHOULD TELL A STORY
RSPEC
describe ‘A User Repository’ do
subject { UserRepository.new }
let(:name) { ‘Machuga’ }
before do
subject.save(User.new(name))
end
after do
subject.clear!
end
it ‘can find a user by name’ do
user = subject.find_by_name(name)
expect(user.name).to eq(name)
end
end
blocks denoted by { } or do..end
Slide 81
Slide 81 text
TESTS SHOULD TELL A STORY
RSPEC
describe ‘A User Repository’ do
subject { UserRepository.new }
let(:name) { ‘Machuga’ }
before do
subject.save(User.new(name))
end
after do
subject.clear!
end
it ‘can find a user by name’ do
user = subject.find_by_name(name)
expect(user.name).to eq(name)
end
end
optional syntax
Slide 82
Slide 82 text
TESTS SHOULD TELL A STORY
RSPEC
describe ‘A User Repository’ do
subject { UserRepository.new }
let(:name) { ‘Machuga’ }
before do
subject.save(User.new(name))
end
after do
subject.clear!
end
it ‘can find a user by name’ do
user = subject.find_by_name(name)
expect(user.name).to eq(name)
end
end
new is a method on the class
Slide 83
Slide 83 text
TESTS SHOULD TELL A STORY
RSPEC
describe ‘A User Repository’ do
subject { UserRepository.new }
let(:name) { ‘Machuga’ }
before do
subject.save(User.new(name))
end
after do
subject.clear!
end
it ‘can find a user by name’ do
user = subject.find_by_name(name)
expect(user.name).to eq(name)
end
end
can use ! and ? in method names
Slide 84
Slide 84 text
5 TIPS FOR SPEC
STORYTELLING
OR: I TRIED THESE 5 WEIRD TRICKS ON MY TESTS;
YOU’LL NEVER GUESS WHAT HAPPENED NEXT!
Slide 85
Slide 85 text
1. BE EXPRESSIVE
Slide 86
Slide 86 text
CUSTOM ACTIONS
FOR COMPLEX BEHAVIOR
Slide 87
Slide 87 text
TESTS SHOULD TELL A STORY
RSPEC ACCEPTANCE TEST
describe 'items' do
it 'should be able to be dragged into categories' do
drag_item_to_category_with_text 'apple', 'a-f'
expect('apple').to be_in_category_with_text(‘a-f')
end
end
Slide 88
Slide 88 text
TESTS SHOULD TELL A STORY
LAYOUT
CHECK NEXT
Slide 89
Slide 89 text
TESTS SHOULD TELL A STORY
LAYOUT
CHECK NEXT
Slide 90
Slide 90 text
TESTS SHOULD TELL A STORY
RSPEC CUSTOM ACTION
# Perform drag and drop on item by name to category by name
def drag_item_to_category_with_text(item_text, category_text)
item(item_text).drag_to category_with_text(category_text)
end
Slide 91
Slide 91 text
TESTS SHOULD TELL A STORY
RSPEC CUSTOM ACTION
# Perform drag and drop on item by name to category by name
def drag_item_to_category_with_text(item_text, category_text)
item(item_text).drag_to category_with_text(category_text)
end
def item(text)
sel = “#{item_prefix}_categorizable_selector”
page.find(send(sel), text: text)
end
def category_with_text(text)
sel = “#{category_prefix}_category_selector”
page.find(send(sel), text: text)
end
Slide 92
Slide 92 text
TESTS SHOULD TELL A STORY
RSPEC ACCEPTANCE TEST REPRISE
describe 'items' do
it 'should be able to be dragged into categories' do
drag_item_to_category_with_text 'apple', 'a-f'
expect('apple').to be_in_category_with_text(‘a-f')
end
end
Slide 93
Slide 93 text
TESTS SHOULD TELL A STORY
RSPEC ACCEPTANCE TEST UNFOLDED
describe 'items' do
it 'should be able to be dragged into categories' do
item = page.find(
send(#{item_prefix}_categorizable_selector”),
text: ‘apple’)
category = page.find(
send(“#{category_prefix}_category_selector”),
text: ‘a-f’)
item.drag_to category
expect('apple').to be_in_category_with_text(‘a-f')
end
end
Slide 94
Slide 94 text
TESTS SHOULD TELL A STORY
RSPEC ACCEPTANCE TEST DOUBLED DOWN
describe 'items' do
it 'should be able to be dragged into categories' do
item1 = page.find(
send("#{item_prefix}_categorizable_selector"),
text: 'apple')
item2 = page.find(
send("#{item_prefix}_categorizable_selector"),
text: 'oranges')
item3 = page.find(
send("#{item_prefix}_categorizable_selector"),
text: 'bananas')
item4 = page.find(
send("#{item_prefix}_categorizable_selector"),
text: 'kiwis')
category = page.find(
send('#{category_prefix}_category_selector'),
text: 'a-f')
item1.drag_to category
item2.drag_to category
item3.drag_to category
item4.drag_to category
expect(uncategorized_items).to be_empty
end
end
Slide 95
Slide 95 text
TESTS SHOULD TELL A STORY
RSPEC ACCEPTANCE TEST DOUBLED DOWN
describe 'items' do
it 'should be able to be dragged into categories' do
item1 = page.find(
send("#{item_prefix}_categorizable_selector"),
text: 'apple')
item2 = page.find(
send("#{item_prefix}_categorizable_selector"),
text: 'oranges')
item3 = page.find(
send("#{item_prefix}_categorizable_selector"),
text: 'bananas')
item4 = page.find(
send("#{item_prefix}_categorizable_selector"),
text: 'kiwis')
category = page.find(
send('#{category_prefix}_category_selector'),
text: 'a-f')
item1.drag_to category
item2.drag_to category
item3.drag_to category
item4.drag_to category
expect(uncategorized_items).to be_empty
end
end
Slide 96
Slide 96 text
TESTS SHOULD TELL A STORY
RSPEC ACCEPTANCE TEST NOPE
describe 'items' do
it 'should be able to be dragged into categories' do
item1 = page.find(
send("#{item_prefix}_categorizable_selector"),
text: 'apple')
item2 = page.find(
send("#{item_prefix}_categorizable_selector"),
text: 'oranges')
item3 = page.find(
send("#{item_prefix}_categorizable_selector"),
text: 'bananas')
item4 = page.find(
send("#{item_prefix}_categorizable_selector"),
text: 'kiwis')
category1 = page.find(
send('#{category_prefix}_category_selector'),
text: 'a-f')
category2 = page.find(
send('#{category_prefix}_category_selector'),
text: 'g-n')
category3 = page.find(
send('#{category_prefix}_category_selector'),
text: 'o-w')
category4 = page.find(
send('#{category_prefix}_category_selector'),
text: 'x-z')
item1.drag_to category1
item2.drag_to category2
item3.drag_to category3
item4.drag_to category4
check_button.click
expect(next_button).to be_enabled
end
end
Slide 97
Slide 97 text
TESTS SHOULD TELL A STORY
RSPEC ACCEPTANCE TEST NOPE
describe 'items' do
it 'should be able to be dragged into categories' do
item1 = page.find(
send("#{item_prefix}_categorizable_selector"),
text: 'apple')
item2 = page.find(
send("#{item_prefix}_categorizable_selector"),
text: 'oranges')
item3 = page.find(
send("#{item_prefix}_categorizable_selector"),
text: 'bananas')
item4 = page.find(
send("#{item_prefix}_categorizable_selector"),
text: 'kiwis')
category1 = page.find(
send('#{category_prefix}_category_selector'),
text: 'a-f')
category2 = page.find(
send('#{category_prefix}_category_selector'),
text: 'g-n')
category3 = page.find(
send('#{category_prefix}_category_selector'),
text: 'o-w')
category4 = page.find(
send('#{category_prefix}_category_selector'),
text: 'x-z')
item1.drag_to category1
item2.drag_to category2
item3.drag_to category3
item4.drag_to category4
check_button.click
expect(next_button).to be_enabled
end
end
Slide 98
Slide 98 text
TESTS ARE CODE
REFACTOR!
Slide 99
Slide 99 text
USE THE BEST
MATCHER / ASSERTION
Slide 100
Slide 100 text
expect((2+2).to_s == 4).to eq true
Slide 101
Slide 101 text
Failures:
1) Hi, Laracon! #
Failure/Error: expect((2+2).to_s == 4).to eq true
expected true
got false
(compared using ==)
# ./testing_spec.rb:3:in `block (2 levels) in '
Finished in 0.02861 seconds (files took 0.16021 seconds to load)
1 example, 1 failure
Failed examples:
rspec ./testing_spec.rb:2 # My awesome example group works
Slide 102
Slide 102 text
expect((2+2).to_s).to eq 4
Slide 103
Slide 103 text
Failures:
1) Hi, Laracon! #
Failure/Error: expect((2+2).to_s).to eq 4
expected: 4
got: "4"
(compared using ==)
# ./testing_spec.rb:3:in `block (2 levels) in '
Finished in 0.01195 seconds (files took 0.13384 seconds to load)
1 example, 1 failure
Failed examples:
rspec ./testing_spec.rb:2 # My awesome example group works
Slide 104
Slide 104 text
CUSTOM
MATCHERS / ASSERTIONS
Slide 105
Slide 105 text
TESTS SHOULD TELL A STORY
LARAVEL CUSTOM ASSERTION
/**
* Asserts that the response contains the given header
* and equals the optional value.
*
* @param string $headerName
* @param mixed $value
* @return $this
*/
protected function seeHeader($headerName, $value = null)
{
$headers = $this->response->headers;
$this->assertTrue($headers->has($headerName), "Header [{$headerName}] not present on
response.");
if (! is_null($value)) {
$this->assertEquals(
$headers->get($headerName), $value,
"Header [{$headerName}] was found, but value [{$headers->get($headerName)}] does
not match [{$value}]."
);
}
return $this;
}
Slide 106
Slide 106 text
TESTS SHOULD TELL A STORY
PHPUNIT CUSTOM ASSERTIONS BLESSED METHOD
Slide 107
Slide 107 text
TESTS SHOULD TELL A STORY
RSPEC CUSTOM MATCHER
require 'rspec/expectations'
RSpec::Matchers.define :be_a_multiple_of do |expected|
match do |actual|
actual % expected == 0
end
failure_message do |actual|
"expected that #{actual} would be a multiple of #{expected}"
end
end
RSpec.describe 9 do
it ‘should blow up and be helpful’ do
expect(9).to be_a_multiple_of(4)
end
end
Failures:
1) 9 should blow up and be helpful
Failure/Error: expect(9).to be_a_multiple_of(4)
expected that 9 would be a multiple of 4
Slide 108
Slide 108 text
2. RESPECT THE CUKES
Slide 109
Slide 109 text
TESTS SHOULD TELL A STORY
CUCUMBER
Slide 110
Slide 110 text
TESTS SHOULD TELL A STORY
USER STORIES AS GHERKIN SPECS
Feature: Getting Laracon attendees test their code
In order to convince Laracon attendees to test their code
As a speaker
I want to provide helpful information and entertainment
Scenario: Adam Wathan gives a TDD talk prior to my talk
Given that attendees recently saw Adam’s talk
And I was in the audience
When I go to give my talk
Then I can make some assumptions on what attendees know
And I can weep as a rearrange my slide deck
Slide 111
Slide 111 text
TESTS SHOULD TELL A STORY
USER STORIES AS RSPEC SPECS
describe ‘Convincing Laracon attendees to test their code’ do
describe ‘Giving a talk as a speaker’ do
context ‘Adam Wathan gives a TDD talk the day before’ do
it ‘can make some assumptions on what attendees know’
it ‘can weep while rearranging slide deck’
end
end
end
Slide 112
Slide 112 text
TESTS SHOULD TELL A STORY
BEHAVIOR-DRIVEN DEVELOPMENT
‣ Describing/designing an application as how it appears to the
stakeholder
‣ Feature-driven workflow
‣ Embraces concepts of the Agile Manifesto
‣ Individuals and interactions over processes and tools
‣ Working software over comprehensive documentation
‣ Customer collaboration over contract negotiation
‣ Responding to change over following a plan
Slide 113
Slide 113 text
3. BAD STORIES ARE SIGNALS
Slide 114
Slide 114 text
TESTS SHOULD TELL A STORY
SMELLS OF BAD STORIES
▸ Plot holes
▸ Lack of Character Development
▸ No Descriptions
▸ Switching narrative
Slide 115
Slide 115 text
TESTS SHOULD TELL A STORY
PLOT HOLES
▸ Mocking the object under test
▸ Global state mutations out of view
▸ Implicit Behavior
Slide 116
Slide 116 text
TESTS SHOULD TELL A STORY
NO DESCRIPTIONS
▸ Creating abstractions that provide no benefit
▸ No explanation why the environment is in current state
▸ The world is bland and empty
Slide 117
Slide 117 text
TESTS SHOULD TELL A STORY
LACK OF CHARACTER DEVELOPMENT
▸ Performing transformations on characters out of view
▸ Mocking collaborators without clear reason
Slide 118
Slide 118 text
TESTS SHOULD TELL A STORY
SWITCHING NARRATIVES
▸ Setting expectations on collaborators
▸ Blurring lines between suites
Slide 119
Slide 119 text
4. UNIT TEST IN ISOLATION
Slide 120
Slide 120 text
MORE ON THIS SOON
Slide 121
Slide 121 text
5. TRY TDD/BDD
Slide 122
Slide 122 text
TWO WEEKS
Slide 123
Slide 123 text
TESTS SHOULD TELL A STORY
FEATURE-FIRST
▸ Build only what your client needs at that moment
▸ Supports slice plans
▸ Waste few resources to test an idea
▸ Provides readable, agreed upon specs for stakeholders
▸ Encourages collaboration
Slide 124
Slide 124 text
TESTS SHOULD TELL A STORY
DRIVING YOUR DESIGN & CODE
Slide 125
Slide 125 text
TESTS SHOULD TELL A STORY
DRIVING YOUR DESIGN & CODE
▸ Write failing test first
▸ Evidence feature is incomplete
▸ Evidence feature is not coincidently passing
Slide 126
Slide 126 text
TESTS SHOULD TELL A STORY
DRIVING YOUR DESIGN & CODE
▸ Write failing test first
▸ Evidence feature is incomplete
▸ Evidence feature is not coincidently passing
▸ Write smallest amount of code
▸ Evidence necessary code to solve that use-case is implemented
Slide 127
Slide 127 text
TESTS SHOULD TELL A STORY
DRIVING YOUR DESIGN & CODE
▸ Write failing test first
▸ Evidence feature is incomplete
▸ Evidence feature is not coincidently passing
▸ Write smallest amount of code
▸ Evidence necessary code to solve that use-case is implemented
▸ Listen to feedback & refactor code & test in pieces
▸ Confidence nothing is broken
▸ Aids in better design
Slide 128
Slide 128 text
TESTS SHOULD TELL A STORY
DRIVING YOUR DESIGN & CODE
▸ Write failing test first
▸ Evidence feature is incomplete
▸ Evidence feature is not coincidently passing
▸ Write smallest amount of code
▸ Evidence necessary code to solve that use-case is implemented
▸ Listen to feedback & refactor code & test in pieces
▸ Confidence nothing is broken
▸ Aids in better design
▸ Taking small steps
▸ Ensures frequent save points
Slide 129
Slide 129 text
TIME FOR A STORY
WARNING: MATH AHEAD
Slide 130
Slide 130 text
No content
Slide 131
Slide 131 text
TESTS SHOULD TELL A STORY
LMS
▸ Per School Year
▸ ~ 3 Million Students
▸ ~ 2 Million Live Help Sessions
▸ ~ 1 Billion Math Problems
▸ Math Content Quantity Comparable to Khan Academy
▸ A gigantic Rails monolith + two SPA’s
Slide 132
Slide 132 text
No content
Slide 133
Slide 133 text
TESTS SHOULD TELL A STORY
LIVE HELP
▸ Teachers available to help students
▸ Voice
▸ Text
▸ Whiteboard
Slide 134
Slide 134 text
No content
Slide 135
Slide 135 text
No content
Slide 136
Slide 136 text
TESTS SHOULD TELL A STORY
LIVE HELP
▸ Originally in Flash
▸ Reimagined & Rewritten in 2013
▸ Goals of rewrite
▸ Decrease wait time of over 2 minutes
▸ Work on iPad
▸ Improve performance and maintainability
▸ Better pairing of teachers to students
Slide 137
Slide 137 text
TESTS SHOULD TELL A STORY
LIVE HELP
▸ Rewrote in CoffeeScript with Node & Angular
▸ Great Success
▸ Throughput bumped to the current level
▸ Wait times decreased to typically < 15 seconds
▸ Compatible with iPad
▸ Improved pairing students to teachers
Slide 138
Slide 138 text
TESTS SHOULD TELL A STORY
LIVE HELP
▸ Left largely untouched until big update in late 2015
▸ Compiled all CoffeeScript to JS, switched to ES2015
▸ Simplified server-side to boost performance + scaling
Slide 139
Slide 139 text
THE PAIRING ALGORITHM
Slide 140
Slide 140 text
No content
Slide 141
Slide 141 text
TESTS SHOULD TELL A STORY
LIVE HELP PAIRING ALGORITHM
▸ Time-based weighting queue
▸ Grows linearly over time
▸ Those who are waiting longer get selected first
▸ Bonus weighting for teachers/students speaking same language
▸ Adds large offset that tapers over time
▸ Offset becomes 0 at threshold
▸ Fastpass match weight - Guaranteed win
Slide 142
Slide 142 text
TESTS SHOULD TELL A STORY
GRAPHS!
Weight Points
0
5000
10000
15000
20000
Seconds
0 5 10 15 20
Student w/ Language Mismatch
Student w/ Language Match
Slide 143
Slide 143 text
TESTS SHOULD TELL A STORY
LIVE HELP PAIRING ALGORITHM - WITHIN THRESHOLD
Given a language boost threshold of 15000
And EnglishStudent1 has waited 11s
And SpanishStudent1 has waited 6s (13.5s)
When a Spanish Teacher pulls in another student
Then that student will be SpanishStudent1
Weight
Points
0
15000
30000
Seconds
0 5 10 15 20 25 30
English Student Spanish Student
Slide 144
Slide 144 text
TESTS SHOULD TELL A STORY
LIVE HELP PAIRING ALGORITHM - WITHIN THRESHOLD
Given a language boost threshold of 15000
And EnglishStudent1 has waited 11s
And SpanishStudent1 has waited 6s (13.5s)
When a Spanish Teacher pulls in another student
Then that student will be SpanishStudent1
Weight
Points
0
15000
30000
Seconds
0 5 10 15 20 25 30
English Student Spanish Student
Slide 145
Slide 145 text
TESTS SHOULD TELL A STORY
LIVE HELP PAIRING ALGORITHM - PAST THRESHOLD
Given a language boost threshold of 15000
And EnglishStudent1 has waited 20s
And SpanishStudent1 has waited 15s (15s)
When a Spanish Teacher pulls in another student
Then that student will be EnglishStudent1
Weight
Points
0
15000
30000
Seconds
0 5 10 15 20 25 30
English Student Spanish Student
Slide 146
Slide 146 text
REFACTORING SPECS
Slide 147
Slide 147 text
TESTS SHOULD TELL A STORY
PREVIOUS SPEC (COMPILED FROM COFFEESCRIPT)
describe("PairMatcher", function() {
describe("Pair scoring order", function() {
describe("Spanish speaking teachers", function() {
beforeEach(function() {
this.students = [
this.helper.createSpanishStudent(), this.helper.createEnglishStudent(),
this.helper.createSpanishStudent(), this.helper.createStudent()
];
this.matcher = new PairMatcher(this.students);
});
it("will prefer new Spanish speaking students", function() {
var match1, match2;
this.offsetStudentTimes();
match1 = this.matcher.getNextStudentFor(this.spanishTeacher);
this.removeStudent(match1);
match2 = this.matcher.getNextStudentFor(this.spanishTeacher);
expect(match1.getLanguage()).toBe('es');
expect(match2.getLanguage()).toBe('es');
});
});
});
});
Slide 148
Slide 148 text
TESTS SHOULD TELL A STORY
EXISTING SPEC
describe(“PairMatcher Pair scoring order for Spanish speaking teachers", function() {
beforeEach(function() {
this.students = [
this.helper.createSpanishStudent(),
this.helper.createEnglishStudent(),
this.helper.createSpanishStudent(),
this.helper.createStudent()
];
this.matcher = new PairMatcher(this.students);
});
it("will prefer new Spanish speaking students", function() {
this.offsetStudentTimes();
var match1 = this.matcher.getNextStudentFor(this.spanishTeacher);
this.removeStudent(match1);
var match2 = this.matcher.getNextStudentFor(this.spanishTeacher);
expect(match1.getLanguage()).toBe(‘es’);
expect(match2.getLanguage()).toBe('es');
});
});
Slide 149
Slide 149 text
TESTS SHOULD TELL A STORY
EXISTING SPEC
describe(“PairMatcher Pair scoring order for Spanish speaking teachers", function() {
beforeEach(function() {
this.students = [
this.helper.createSpanishStudent(),
this.helper.createEnglishStudent(),
this.helper.createSpanishStudent(),
this.helper.createStudent()
];
this.matcher = new PairMatcher(this.students);
});
it("will prefer new Spanish speaking students", function() {
this.offsetStudentTimes();
var match1 = this.matcher.getNextStudentFor(this.spanishTeacher);
this.removeStudent(match1);
var match2 = this.matcher.getNextStudentFor(this.spanishTeacher);
expect(match1.getLanguage()).toBe(‘es’);
expect(match2.getLanguage()).toBe('es');
});
});
Slide 150
Slide 150 text
TESTS SHOULD TELL A STORY
EXISTING SPEC
describe(“PairMatcher Pair scoring order for Spanish speaking teachers", function() {
beforeEach(function() {
this.students = [
this.helper.createSpanishStudent(),
this.helper.createEnglishStudent(),
this.helper.createSpanishStudent(),
this.helper.createStudent()
];
this.matcher = new PairMatcher(this.students);
});
it("will prefer new Spanish speaking students", function() {
this.offsetStudentTimes();
var match1 = this.matcher.getNextStudentFor(this.spanishTeacher);
this.removeStudent(match1);
var match2 = this.matcher.getNextStudentFor(this.spanishTeacher);
expect(match1.getLanguage()).toBe(‘es’);
expect(match2.getLanguage()).toBe('es');
});
});
Slide 151
Slide 151 text
TESTS SHOULD TELL A STORY
EXISTING SPEC
describe(“PairMatcher Pair scoring order for Spanish speaking teachers", function() {
beforeEach(function() {
this.students = [
this.helper.createSpanishStudent(),
this.helper.createEnglishStudent(),
this.helper.createSpanishStudent(),
this.helper.createStudent()
];
this.matcher = new PairMatcher(this.students);
});
it("will prefer new Spanish speaking students", function() {
this.offsetStudentTimes();
var match1 = this.matcher.getNextStudentFor(this.spanishTeacher);
this.removeStudent(match1);
var match2 = this.matcher.getNextStudentFor(this.spanishTeacher);
expect(match1.getLanguage()).toBe(‘es’);
expect(match2.getLanguage()).toBe('es');
});
});
WHAT LANGUAGE DOES
STUDENT SPEAK?
Slide 152
Slide 152 text
TESTS SHOULD TELL A STORY
EXISTING SPEC
describe(“PairMatcher Pair scoring order for Spanish speaking teachers", function() {
beforeEach(function() {
this.students = [
this.helper.createSpanishStudent(),
this.helper.createEnglishStudent(),
this.helper.createSpanishStudent(),
this.helper.createStudent()
];
this.matcher = new PairMatcher(this.students);
});
it("will prefer new Spanish speaking students", function() {
this.offsetStudentTimes();
var match1 = this.matcher.getNextStudentFor(this.spanishTeacher);
this.removeStudent(match1);
var match2 = this.matcher.getNextStudentFor(this.spanishTeacher);
expect(match1.getLanguage()).toBe(‘es’);
expect(match2.getLanguage()).toBe('es');
});
});
Slide 153
Slide 153 text
TESTS SHOULD TELL A STORY
EXISTING SPEC
describe(“PairMatcher Pair scoring order for Spanish speaking teachers", function() {
beforeEach(function() {
this.students = [
this.helper.createSpanishStudent(),
this.helper.createEnglishStudent(),
this.helper.createSpanishStudent(),
this.helper.createStudent()
];
this.matcher = new PairMatcher(this.students);
});
it("will prefer new Spanish speaking students", function() {
this.offsetStudentTimes();
var match1 = this.matcher.getNextStudentFor(this.spanishTeacher);
this.removeStudent(match1);
var match2 = this.matcher.getNextStudentFor(this.spanishTeacher);
expect(match1.getLanguage()).toBe(‘es’);
expect(match2.getLanguage()).toBe('es');
});
});
Slide 154
Slide 154 text
TESTS SHOULD TELL A STORY
EXISTING SPEC
describe(“PairMatcher Pair scoring order for Spanish speaking teachers", function() {
beforeEach(function() {
this.students = [
this.helper.createSpanishStudent(),
this.helper.createEnglishStudent(),
this.helper.createSpanishStudent(),
this.helper.createStudent()
];
this.matcher = new PairMatcher(this.students);
});
it("will prefer new Spanish speaking students", function() {
this.offsetStudentTimes();
var match1 = this.matcher.getNextStudentFor(this.spanishTeacher);
this.removeStudent(match1);
var match2 = this.matcher.getNextStudentFor(this.spanishTeacher);
expect(match1.getLanguage()).toBe(‘es’);
expect(match2.getLanguage()).toBe('es');
});
});
WTF IS THIS?
Slide 155
Slide 155 text
TESTS SHOULD TELL A STORY
EXISTING SPEC
describe(“PairMatcher Pair scoring order for Spanish speaking teachers", function() {
beforeEach(function() {
this.students = [
this.helper.createSpanishStudent(),
this.helper.createEnglishStudent(),
this.helper.createSpanishStudent(),
this.helper.createStudent()
];
this.matcher = new PairMatcher(this.students);
});
it("will prefer new Spanish speaking students", function() {
this.offsetStudentTimes();
var match1 = this.matcher.getNextStudentFor(this.spanishTeacher);
this.removeStudent(match1);
var match2 = this.matcher.getNextStudentFor(this.spanishTeacher);
expect(match1.getLanguage()).toBe(‘es’);
expect(match2.getLanguage()).toBe('es');
});
});
WTF IS THIS?
ADD OPTIONAL OFFSET
STAGGER WAIT TIMES
REVERSE CHRONOLOGICALLY
Slide 156
Slide 156 text
TESTS SHOULD TELL A STORY
EXISTING SPEC
describe(“PairMatcher Pair scoring order for Spanish speaking teachers", function() {
beforeEach(function() {
this.students = [
this.helper.createSpanishStudent(),
this.helper.createEnglishStudent(),
this.helper.createSpanishStudent(),
this.helper.createStudent()
];
this.matcher = new PairMatcher(this.students);
});
it("will prefer new Spanish speaking students", function() {
this.offsetStudentTimes();
var match1 = this.matcher.getNextStudentFor(this.spanishTeacher);
this.removeStudent(match1);
var match2 = this.matcher.getNextStudentFor(this.spanishTeacher);
expect(match1.getLanguage()).toBe(‘es’);
expect(match2.getLanguage()).toBe('es');
});
});
Slide 157
Slide 157 text
TESTS SHOULD TELL A STORY
EXISTING SPEC
describe(“PairMatcher Pair scoring order for Spanish speaking teachers", function() {
beforeEach(function() {
this.students = [
this.helper.createSpanishStudent(),
this.helper.createEnglishStudent(),
this.helper.createSpanishStudent(),
this.helper.createStudent()
];
this.matcher = new PairMatcher(this.students);
});
it("will prefer new Spanish speaking students", function() {
this.offsetStudentTimes();
var match1 = this.matcher.getNextStudentFor(this.spanishTeacher);
this.removeStudent(match1);
var match2 = this.matcher.getNextStudentFor(this.spanishTeacher);
expect(match1.getLanguage()).toBe(‘es’);
expect(match2.getLanguage()).toBe('es');
});
});
WUT?
Slide 158
Slide 158 text
TESTS SHOULD TELL A STORY
EXISTING SPEC
describe(“PairMatcher Pair scoring order for Spanish speaking teachers", function() {
beforeEach(function() {
this.students = [
this.helper.createSpanishStudent(),
this.helper.createEnglishStudent(),
this.helper.createSpanishStudent(),
this.helper.createStudent()
];
this.matcher = new PairMatcher(this.students);
});
it("will prefer new Spanish speaking students", function() {
this.offsetStudentTimes();
var match1 = this.matcher.getNextStudentFor(this.spanishTeacher);
this.removeStudent(match1);
var match2 = this.matcher.getNextStudentFor(this.spanishTeacher);
expect(match1.getLanguage()).toBe(‘es’);
expect(match2.getLanguage()).toBe('es');
});
});
Slide 159
Slide 159 text
TESTS SHOULD TELL A STORY
THE OLD STORY
Describe the pair order for Spanish speaking teachers
Given this list of four students [es, en, es, en]
And all have wait times within the language threshold
And each is waiting longer than the previous
When the teacher pulls two new students
Then the teacher should receive the Spanish speaking students
Slide 160
Slide 160 text
TESTS SHOULD TELL A STORY
THE OLD STORY
describe(“PairMatcher Pair scoring order for Spanish speaking teachers", function() {
beforeEach(function() {
this.students = [
this.helper.createSpanishStudent(),
this.helper.createEnglishStudent(),
this.helper.createSpanishStudent(),
this.helper.createStudent()
];
this.matcher = new PairMatcher(this.students);
});
it("will prefer new Spanish speaking students", function() {
this.offsetStudentTimes();
var match1 = this.matcher.getNextStudentFor(this.spanishTeacher);
this.removeStudent(match1);
var match2 = this.matcher.getNextStudentFor(this.spanishTeacher);
expect(match1.getLanguage()).toBe(‘es’);
expect(match2.getLanguage()).toBe('es');
});
});
THE PROLOGUE
Slide 161
Slide 161 text
TESTS SHOULD TELL A STORY
THE OLD STORY
describe(“PairMatcher Pair scoring order for Spanish speaking teachers", function() {
beforeEach(function() {
this.students = [
this.helper.createSpanishStudent(),
this.helper.createEnglishStudent(),
this.helper.createSpanishStudent(),
this.helper.createStudent()
];
this.matcher = new PairMatcher(this.students);
});
it("will prefer new Spanish speaking students", function() {
this.offsetStudentTimes();
var match1 = this.matcher.getNextStudentFor(this.spanishTeacher);
this.removeStudent(match1);
var match2 = this.matcher.getNextStudentFor(this.spanishTeacher);
expect(match1.getLanguage()).toBe(‘es’);
expect(match2.getLanguage()).toBe('es');
});
});
THE SUPPORTING CAST
Slide 162
Slide 162 text
TESTS SHOULD TELL A STORY
THE OLD STORY
describe(“PairMatcher Pair scoring order for Spanish speaking teachers", function() {
beforeEach(function() {
this.students = [
this.helper.createSpanishStudent(),
this.helper.createEnglishStudent(),
this.helper.createSpanishStudent(),
this.helper.createStudent()
];
this.matcher = new PairMatcher(this.students);
});
it("will prefer new Spanish speaking students", function() {
this.offsetStudentTimes();
var match1 = this.matcher.getNextStudentFor(this.spanishTeacher);
this.removeStudent(match1);
var match2 = this.matcher.getNextStudentFor(this.spanishTeacher);
expect(match1.getLanguage()).toBe(‘es’);
expect(match2.getLanguage()).toBe('es');
});
});
THE PROTAGONIST
Slide 163
Slide 163 text
TESTS SHOULD TELL A STORY
THE OLD STORY
describe(“PairMatcher Pair scoring order for Spanish speaking teachers", function() {
beforeEach(function() {
this.students = [
this.helper.createSpanishStudent(),
this.helper.createEnglishStudent(),
this.helper.createSpanishStudent(),
this.helper.createStudent()
];
this.matcher = new PairMatcher(this.students);
});
it("will prefer new Spanish speaking students", function() {
this.offsetStudentTimes();
var match1 = this.matcher.getNextStudentFor(this.spanishTeacher);
this.removeStudent(match1);
var match2 = this.matcher.getNextStudentFor(this.spanishTeacher);
expect(match1.getLanguage()).toBe(‘es’);
expect(match2.getLanguage()).toBe('es');
});
});
THE PLOT
Slide 164
Slide 164 text
TESTS SHOULD TELL A STORY
THE OLD STORY
describe(“PairMatcher Pair scoring order for Spanish speaking teachers", function() {
beforeEach(function() {
this.students = [
this.helper.createSpanishStudent(),
this.helper.createEnglishStudent(),
this.helper.createSpanishStudent(),
this.helper.createStudent()
];
this.matcher = new PairMatcher(this.students);
});
it("will prefer new Spanish speaking students", function() {
this.offsetStudentTimes();
var match1 = this.matcher.getNextStudentFor(this.spanishTeacher);
this.removeStudent(match1);
var match2 = this.matcher.getNextStudentFor(this.spanishTeacher);
expect(match1.getLanguage()).toBe(‘es’);
expect(match2.getLanguage()).toBe('es');
});
});
M. NIGHT SHYMALAN TWIST &
NO CHARACTER DEVELOPMENT
Slide 165
Slide 165 text
TESTS SHOULD TELL A STORY
THE OLD STORY
describe(“PairMatcher Pair scoring order for Spanish speaking teachers", function() {
beforeEach(function() {
this.students = [
this.helper.createSpanishStudent(),
this.helper.createEnglishStudent(),
this.helper.createSpanishStudent(),
this.helper.createStudent()
];
this.matcher = new PairMatcher(this.students);
});
it("will prefer new Spanish speaking students", function() {
this.offsetStudentTimes();
var match1 = this.matcher.getNextStudentFor(this.spanishTeacher);
this.removeStudent(match1);
var match2 = this.matcher.getNextStudentFor(this.spanishTeacher);
expect(match1.getLanguage()).toBe(‘es’);
expect(match2.getLanguage()).toBe('es');
});
});
THE CONFLICT
Slide 166
Slide 166 text
TESTS SHOULD TELL A STORY
THE OLD STORY
describe(“PairMatcher Pair scoring order for Spanish speaking teachers", function() {
beforeEach(function() {
this.students = [
this.helper.createSpanishStudent(),
this.helper.createEnglishStudent(),
this.helper.createSpanishStudent(),
this.helper.createStudent()
];
this.matcher = new PairMatcher(this.students);
});
it("will prefer new Spanish speaking students", function() {
this.offsetStudentTimes();
var match1 = this.matcher.getNextStudentFor(this.spanishTeacher);
this.removeStudent(match1);
var match2 = this.matcher.getNextStudentFor(this.spanishTeacher);
expect(match1.getLanguage()).toBe(‘es’);
expect(match2.getLanguage()).toBe('es');
});
});
PLOT HOLE
Slide 167
Slide 167 text
TESTS SHOULD TELL A STORY
THE OLD STORY
describe(“PairMatcher Pair scoring order for Spanish speaking teachers", function() {
beforeEach(function() {
this.students = [
this.helper.createSpanishStudent(),
this.helper.createEnglishStudent(),
this.helper.createSpanishStudent(),
this.helper.createStudent()
];
this.matcher = new PairMatcher(this.students);
});
it("will prefer new Spanish speaking students", function() {
this.offsetStudentTimes();
var match1 = this.matcher.getNextStudentFor(this.spanishTeacher);
this.removeStudent(match1);
var match2 = this.matcher.getNextStudentFor(this.spanishTeacher);
expect(match1.getLanguage()).toBe(‘es’);
expect(match2.getLanguage()).toBe('es');
});
});
BREAKING DOWN THE 4TH WALL
Slide 168
Slide 168 text
TESTS SHOULD TELL A STORY
THE OLD STORY
describe(“PairMatcher Pair scoring order for Spanish speaking teachers", function() {
beforeEach(function() {
this.students = [
this.helper.createSpanishStudent(),
this.helper.createEnglishStudent(),
this.helper.createSpanishStudent(),
this.helper.createStudent()
];
this.matcher = new PairMatcher(this.students);
});
it("will prefer new Spanish speaking students", function() {
this.offsetStudentTimes();
var match1 = this.matcher.getNextStudentFor(this.spanishTeacher);
this.removeStudent(match1);
var match2 = this.matcher.getNextStudentFor(this.spanishTeacher);
expect(match1.getLanguage()).toBe(‘es’);
expect(match2.getLanguage()).toBe('es');
});
});
THE RESOLUTION
Slide 169
Slide 169 text
TESTS SHOULD TELL A STORY
GOOD THINGS ABOUT THIS SPEC
Slide 170
Slide 170 text
TESTS SHOULD TELL A STORY
GOOD THINGS ABOUT THIS SPEC
▸ Mostly clear name for example group and test description
Slide 171
Slide 171 text
TESTS SHOULD TELL A STORY
GOOD THINGS ABOUT THIS SPEC
▸ Mostly clear name for example group and test description
▸ Using this (disposable context in Jasmine)
Slide 172
Slide 172 text
TESTS SHOULD TELL A STORY
GOOD THINGS ABOUT THIS SPEC
▸ Mostly clear name for example group and test description
▸ Using this (disposable context in Jasmine)
▸ Assertions match description
Slide 173
Slide 173 text
TESTS SHOULD TELL A STORY
NOT-SO-GOOD THINGS ABOUT THIS SPEC
Slide 174
Slide 174 text
TESTS SHOULD TELL A STORY
NOT-SO-GOOD THINGS ABOUT THIS SPEC
▸ Helpers cause side-effects (offsetTimes, removeStudent)
Slide 175
Slide 175 text
TESTS SHOULD TELL A STORY
NOT-SO-GOOD THINGS ABOUT THIS SPEC
▸ Helpers cause side-effects (offsetTimes, removeStudent)
▸ Object under test has dependency mutated after use
Slide 176
Slide 176 text
TESTS SHOULD TELL A STORY
NOT-SO-GOOD THINGS ABOUT THIS SPEC
▸ Helpers cause side-effects (offsetTimes, removeStudent)
▸ Object under test has dependency mutated after use
▸ Character development happens off-screen
Slide 177
Slide 177 text
TESTS SHOULD TELL A STORY
NOT-SO-GOOD THINGS ABOUT THIS SPEC
▸ Helpers cause side-effects (offsetTimes, removeStudent)
▸ Object under test has dependency mutated after use
▸ Character development happens off-screen
▸ Expectations are dependent on result of side-effects
Slide 178
Slide 178 text
TESTS SHOULD TELL A STORY
NOT-SO-GOOD THINGS ABOUT THIS SPEC
▸ Helpers cause side-effects (offsetTimes, removeStudent)
▸ Object under test has dependency mutated after use
▸ Character development happens off-screen
▸ Expectations are dependent on result of side-effects
▸ Three methods of creating a student are used
Slide 179
Slide 179 text
TESTS PASS
SPANISH STUDENTS ARE PULLED FIRST
Slide 180
Slide 180 text
TESTS SHOULD TELL A STORY
THE NEW STORY
Describe A Spanish Speaking teacher pulling students with
the same language
Given all wait times are within the threshold
And englishStudent1 has been waiting 3s
And spanishStudent2 has been waiting 2s
And spanishStudent1 has been waiting 1s
When the teacher pulls the next student
Then the teacher should receive spanishStudent2
Slide 181
Slide 181 text
TESTS SHOULD TELL A STORY
THE NEW STORY
describe('StudentTeacherScorer', function() {
var sessions = [];
//…
describe('A teacher speaking same language as a student', function() {
beforeEach(function() {
spanishStudent1.waitTime = 1000;
spanishStudent2.waitTime = 2000;
englishStudent1.waitTime = 3000;
sessions.push(englishStudent1);
sessions.push(spanishStudent2);
sessions.push(spanishStudent1);
});
it('will pick the student waiting longest', function() {
const chosenStudent = scorer.findBestMatchFor(sessions, spanishTeacher);
expect(chosenStudent).toEqual(spanishStudent2);
});
});
});
Slide 182
Slide 182 text
TESTS SHOULD TELL A STORY
THE NEW STORY
describe('StudentTeacherScorer', function() {
var sessions = [];
//…
describe('A teacher speaking same language as a student', function() {
beforeEach(function() {
spanishStudent1.waitTime = 1000;
spanishStudent2.waitTime = 2000;
englishStudent1.waitTime = 3000;
sessions.push(englishStudent1);
sessions.push(spanishStudent2);
sessions.push(spanishStudent1);
});
it('will pick the student waiting longest', function() {
const chosenStudent = scorer.findBestMatchFor(sessions, spanishTeacher);
expect(chosenStudent).toEqual(spanishStudent2);
});
});
});
THE PROLOGUE
Slide 183
Slide 183 text
TESTS SHOULD TELL A STORY
THE NEW STORY
describe('StudentTeacherScorer', function() {
var sessions = [];
//…
describe('A teacher speaking same language as a student', function() {
beforeEach(function() {
spanishStudent1.waitTime = 1000;
spanishStudent2.waitTime = 2000;
englishStudent1.waitTime = 3000;
sessions.push(englishStudent1);
sessions.push(spanishStudent2);
sessions.push(spanishStudent1);
});
it('will pick the student waiting longest', function() {
const chosenStudent = scorer.findBestMatchFor(sessions, spanishTeacher);
expect(chosenStudent).toEqual(spanishStudent2);
});
});
});
CHARACTER DEVELOPMENT
Slide 184
Slide 184 text
TESTS SHOULD TELL A STORY
THE NEW STORY
describe('StudentTeacherScorer', function() {
var sessions = [];
//…
describe('A teacher speaking same language as a student', function() {
beforeEach(function() {
spanishStudent1.waitTime = 1000;
spanishStudent2.waitTime = 2000;
englishStudent1.waitTime = 3000;
sessions.push(englishStudent1);
sessions.push(spanishStudent2);
sessions.push(spanishStudent1);
});
it('will pick the student waiting longest', function() {
const chosenStudent = scorer.findBestMatchFor(sessions, spanishTeacher);
expect(chosenStudent).toEqual(spanishStudent2);
});
});
});
THE CHOSEN ONE
Slide 185
Slide 185 text
TESTS SHOULD TELL A STORY
THE NEW STORY
describe('StudentTeacherScorer', function() {
var sessions = [];
//…
describe('A teacher speaking same language as a student', function() {
beforeEach(function() {
spanishStudent1.waitTime = 1000;
spanishStudent2.waitTime = 2000;
englishStudent1.waitTime = 3000;
sessions.push(englishStudent1);
sessions.push(spanishStudent2);
sessions.push(spanishStudent1);
});
it('will pick the student waiting longest', function() {
const chosenStudent = scorer.findBestMatchFor(sessions, spanishTeacher);
expect(chosenStudent).toEqual(spanishStudent2);
});
});
});
THE PLOT
Slide 186
Slide 186 text
TESTS SHOULD TELL A STORY
THE NEW STORY
describe('StudentTeacherScorer', function() {
var sessions = [];
//…
describe('A teacher speaking same language as a student', function() {
beforeEach(function() {
spanishStudent1.waitTime = 1000;
spanishStudent2.waitTime = 2000;
englishStudent1.waitTime = 3000;
sessions.push(englishStudent1);
sessions.push(spanishStudent2);
sessions.push(spanishStudent1);
});
it('will pick the student waiting longest', function() {
const chosenStudent = scorer.findBestMatchFor(sessions, spanishTeacher);
expect(chosenStudent).toEqual(spanishStudent2);
});
});
});
THE CONFLICT
Slide 187
Slide 187 text
TESTS SHOULD TELL A STORY
THE NEW STORY
describe('StudentTeacherScorer', function() {
var sessions = [];
//…
describe('A teacher speaking same language as a student', function() {
beforeEach(function() {
spanishStudent1.waitTime = 1000;
spanishStudent2.waitTime = 2000;
englishStudent1.waitTime = 3000;
sessions.push(englishStudent1);
sessions.push(spanishStudent2);
sessions.push(spanishStudent1);
});
it('will pick the student waiting longest', function() {
const chosenStudent = scorer.findBestMatchFor(sessions, spanishTeacher);
expect(chosenStudent).toEqual(spanishStudent2);
});
});
});
THE RESOLUTION
Slide 188
Slide 188 text
TESTS FAIL
Slide 189
Slide 189 text
TESTS FAIL
Expected: spanishStudent2
Actual: spanishStudent1
Slide 190
Slide 190 text
No content
Slide 191
Slide 191 text
spanishStudent1.waitTime = 1000;
spanishStudent2.waitTime = 2000;
Slide 192
Slide 192 text
1000 > 2000?
spanishStudent1.waitTime = 1000;
spanishStudent2.waitTime = 2000;
Slide 193
Slide 193 text
1000 > 2000?
spanishStudent1.waitTime = 1000;
spanishStudent2.waitTime = 2000;
Slide 194
Slide 194 text
EXISTING BEHAVIOR
VERIFIED BY RUNNING THE OLD SPEC
WITH NEW ASSERTIONS
Slide 195
Slide 195 text
A WILD BUG APPEARS
MATH TO THE RESCUE!
Slide 196
Slide 196 text
TESTS SHOULD TELL A STORY
I AM AWFUL AT SPREADSHEETS
Score w/ Language
Language Weight
Normal Score
X-axis: Time
Y-axis: Score
Slide 197
Slide 197 text
TESTS SHOULD TELL A STORY
I AM AWFUL AT SPREADSHEETS
Lang score
decreased
over time till
negated
Score w/ Language
Language Weight
Normal Score
X-axis: Time
Y-axis: Score
Slide 198
Slide 198 text
TESTS SHOULD TELL A STORY
I AM AWFUL AT SPREADSHEETS
Score should
always
increase
Lang score
decreased
over time till
negated
Score w/ Language
Language Weight
Normal Score
X-axis: Time
Y-axis: Score
Slide 199
Slide 199 text
WHAT DID WE DO ABOUT IT?
Slide 200
Slide 200 text
TESTS SHOULD TELL A STORY
HACK THE PLANET
it('will pick the student waiting longest', function() {
const chosenStudent = scorer.findBestMatchFor(sessions, spanishTeacher);
expect(chosenStudent).toEqual(spanishStudent2);
});
Slide 201
Slide 201 text
TESTS SHOULD TELL A STORY
HACK THE PLANET
it('will pick the student waiting shortestlongest', function() {
const chosenStudent = scorer.findBestMatchFor(sessions, spanishTeacher);
expect(chosenStudent).toEqual(spanishStudent2);
});
Slide 202
Slide 202 text
TESTS SHOULD TELL A STORY
HACK THE PLANET
it('will pick the student waiting shortestlongest', function() {
const chosenStudent = scorer.findBestMatchFor(sessions, spanishTeacher);
expect(chosenStudent).toEqual(spanishStudent2);
});
// TODO: This behavior is probably unintended, but the algorithm has not been changed.
// It appears as though students who have waited *less* than the ELL threshold are actually
// processed in the opposite order than we intend. Once they get beyond the ELL threshold
// then wait time correctly influences the student scoring.
Slide 203
Slide 203 text
TALK TO STAKEHOLDERS
Slide 204
Slide 204 text
THEY SAID TO PUNT ON IT
FIX EVENTUALLY
BUT BEEN LIVING WITH IT FOR YEARS
Slide 205
Slide 205 text
No content
Slide 206
Slide 206 text
WE ARE A
PITTSBURGH
COMPANY
Slide 207
Slide 207 text
SO ON THE PUNT RETURN…
Slide 208
Slide 208 text
No content
Slide 209
Slide 209 text
FOUND THE BUG!
Slide 210
Slide 210 text
PAST-SELF FUDGED SOME
MATH
I WORK FOR A MATH COMPANY
i·ro·ny
/ˈīrənē/ noun
Slide 211
Slide 211 text
FIXED THE CALCULATION
REVERTED THE SPEC
Slide 212
Slide 212 text
TESTS PASS
Slide 213
Slide 213 text
HOWEVER…
AN ACCEPTANCE TEST BROKE ELSEWHERE
UNRELATED TO LANGUAGE
Slide 214
Slide 214 text
CURSE JAVASCRIPT
Slide 215
Slide 215 text
No content
Slide 216
Slide 216 text
No content
Slide 217
Slide 217 text
TESTS SHOULD TELL A STORY
IN THIS ACCEPTANCE TEST
Slide 218
Slide 218 text
TESTS SHOULD TELL A STORY
IN THIS ACCEPTANCE TEST
▸ Had an English Speaking teacher accepting fast pass
Slide 219
Slide 219 text
TESTS SHOULD TELL A STORY
IN THIS ACCEPTANCE TEST
▸ Had an English Speaking teacher accepting fast pass
▸ Enqueued a English speaking student
Slide 220
Slide 220 text
TESTS SHOULD TELL A STORY
IN THIS ACCEPTANCE TEST
▸ Had an English Speaking teacher accepting fast pass
▸ Enqueued a English speaking student
▸ Waited a while
Slide 221
Slide 221 text
TESTS SHOULD TELL A STORY
IN THIS ACCEPTANCE TEST
▸ Had an English Speaking teacher accepting fast pass
▸ Enqueued a English speaking student
▸ Waited a while
▸ Enqueued another English speaking student w/ fast pass
Slide 222
Slide 222 text
TESTS SHOULD TELL A STORY
IN THIS ACCEPTANCE TEST
▸ Had an English Speaking teacher accepting fast pass
▸ Enqueued a English speaking student
▸ Waited a while
▸ Enqueued another English speaking student w/ fast pass
▸ Fast pass ensures second student gets max score, no way
to lose
Slide 223
Slide 223 text
WE LOST
Slide 224
Slide 224 text
TEST FIXTURE WASN’T BEING
SET CORRECTLY
Slide 225
Slide 225 text
PATCHED, STILL FAILED
MEANING THIS WAS A PRODUCTION BUG
Slide 226
Slide 226 text
PATCHED CODE
DESERIALIZATION AND CONSTRUCTION
DIFFERED
Slide 227
Slide 227 text
TESTS PASS
Slide 228
Slide 228 text
TESTS SHOULD TELL A STORY
WHAT HAPPENED?
Slide 229
Slide 229 text
TESTS SHOULD TELL A STORY
WHAT HAPPENED?
▸ Earlier bug hid this
▸ Forced shorter times to be favored on language match
▸ Was documented as working the other way
Slide 230
Slide 230 text
TESTS SHOULD TELL A STORY
WHAT HAPPENED?
▸ Earlier bug hid this
▸ Forced shorter times to be favored on language match
▸ Was documented as working the other way
▸ Our acceptance test worked because of order dependency
▸ Only two students, last student was under test and won
favorability
▸ Putting another student closer could have prevented failure
Slide 231
Slide 231 text
MORALS OF THE STORY
Slide 232
Slide 232 text
TESTS SHOULD TELL A STORY
MORALS OF THE STORY
Slide 233
Slide 233 text
TESTS SHOULD TELL A STORY
MORALS OF THE STORY
▸ Favor explicit assertions over potential coincidence
Slide 234
Slide 234 text
TESTS SHOULD TELL A STORY
MORALS OF THE STORY
▸ Favor explicit assertions over potential coincidence
▸ Favor specs that tell the story you need to know
Slide 235
Slide 235 text
TESTS SHOULD TELL A STORY
MORALS OF THE STORY
▸ Favor explicit assertions over potential coincidence
▸ Favor specs that tell the story you need to know
▸ Beware of coincidental truths
Slide 236
Slide 236 text
TESTS SHOULD TELL A STORY
MORALS OF THE STORY
▸ Favor explicit assertions over potential coincidence
▸ Favor specs that tell the story you need to know
▸ Beware of coincidental truths
▸ Don’t be overly clever with fixtures/fake data
Slide 237
Slide 237 text
TESTS SHOULD TELL A STORY
MORALS OF THE STORY
▸ Favor explicit assertions over potential coincidence
▸ Favor specs that tell the story you need to know
▸ Beware of coincidental truths
▸ Don’t be overly clever with fixtures/fake data
▸ Our careers are founded on math - learn more math
Slide 238
Slide 238 text
QUESTIONS?
Slide 239
Slide 239 text
I’M MATT MACHUGA
Twitter, GitHub, Freenode: machuga
Slide 240
Slide 240 text
ERIE, PA
Slide 241
Slide 241 text
ERIE, PA
Slide 242
Slide 242 text
Hiring Software Developers!
TTM IS HIRING!
CONSULTING & TEACHING
Small to medium projects