Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Features
Speaker Deck
PRO
Sign in
Sign up for free
Search
Search
Writing readable tests
Search
Alex Tercete
August 20, 2015
Programming
2
190
Writing readable tests
Lightning Talk presented at the LSCC Talks #14 event.
Alex Tercete
August 20, 2015
Tweet
Share
More Decks by Alex Tercete
See All by Alex Tercete
Making Makefiles
alextercete
0
65
Shipping containers
alextercete
0
53
Parallelism and Symmetry
alextercete
0
220
Porting to .NET Standard
alextercete
0
55
Prepping Commits
alextercete
1
130
The end of your line-endings nightmare
alextercete
0
180
I love sushi, therefore I love rebase
alextercete
0
100
ReadyRoll for DotNet developers
alextercete
0
85
Coding Dojo: The Randori Kata
alextercete
1
500
Other Decks in Programming
See All in Programming
PHPカンファレンス名古屋2025 タスク分解の試行錯誤〜レビュー負荷を下げるために〜
soichi
1
730
Datadog Workflow Automation で圧倒的価値提供
showwin
1
280
5分で理解する SOLID 原則 #phpcon_nagoya
shogogg
1
390
新宿駅構内を三人称視点で探索してみる
satoshi7190
2
120
Visual StudioのGitHub Copilotでいろいろやってみる
tomokusaba
1
210
「個人開発マネタイズ大全」が教えてくれたこと
bani24884
1
270
もう僕は OpenAPI を書きたくない
sgash708
6
1.9k
なぜイベント駆動が必要なのか - CQRS/ESで解く複雑系システムの課題 -
j5ik2o
14
4.7k
PHPのバージョンアップ時にも役立ったAST
matsuo_atsushi
0
230
dbt Pythonモデルで実現するSnowflake活用術
trsnium
0
270
DRFを少しずつ オニオンアーキテクチャに寄せていく DjangoCongress JP 2025
nealle
2
280
PRレビューのお供にDanger
stoticdev
1
240
Featured
See All Featured
Why You Should Never Use an ORM
jnunemaker
PRO
55
9.2k
Designing Experiences People Love
moore
140
23k
Large-scale JavaScript Application Architecture
addyosmani
511
110k
The Psychology of Web Performance [Beyond Tellerrand 2023]
tammyeverts
46
2.4k
Imperfection Machines: The Place of Print at Facebook
scottboms
267
13k
Side Projects
sachag
452
42k
Building Better People: How to give real-time feedback that sticks.
wjessup
367
19k
What's in a price? How to price your products and services
michaelherold
244
12k
ピンチをチャンスに:未来をつくるプロダクトロードマップ #pmconf2020
aki_iinuma
114
51k
Fashionably flexible responsive web design (full day workshop)
malarkey
406
66k
Rebuilding a faster, lazier Slack
samanthasiow
80
8.9k
Building Adaptive Systems
keathley
40
2.4k
Transcript
Writing readable tests Separating mechanics from data Alex Tercete @alextercete
https://www.flickr.com/photos/vdepizzol/8081618546
read- ability?
read- ability
understand- ability
The four elements of readability
https://www.flickr.com/photos/tychosnose/15416119182 Context WHERE
Reader’s Experience https://www.flickr.com/photos/theilr/5048464567 WHO
https://www.flickr.com/photos/thomasclaveirole/463202335 Structure HOW
Content https://www.flickr.com/photos/carinefel/13916816466 WHAT
Structure Mechanics Content Data
https://www.flickr.com/photos/emily3333000/16210254212
[Test] public void Add_two_numbers() { var calculator = new RpnCalculator();
calculator.Push(5); calculator.Push(3); Assert.That(calculator.Add(), Is.EqualTo(8)); } [Test] public void Add_two_numbers() { var calculator = new RpnCalculator(); calculator.Push(5); calculator.Push(3); Assert.That(calculator.Add(), Is.EqualTo(8)); }
[Test] public void Subtract_two_numbers() { var calculator = new RpnCalculator();
calculator.Push(5); calculator.Push(3); Assert.That(calculator.Subtract(), Is.EqualTo(2)); } [Test] public void Add_two_numbers() { var calculator = new RpnCalculator(); calculator.Push(5); calculator.Push(3); Assert.That(calculator.Add(), Is.EqualTo(8)); } [Test] public void Subtract_two_numbers() { var calculator = new RpnCalculator(); calculator.Push(5); calculator.Push(3); Assert.That(calculator.Subtract(), Is.EqualTo(2)); }
Don’t Repeat Yourself
[SetUp] public void SetUp() { _calculator = new RpnCalculator(); _calculator.Push(5);
_calculator.Push(3); } [Test] public void Add_two_numbers() { Assert.That(_calculator.Add(), Is.EqualTo(8)); } private RpnCalculator _calculator; [SetUp] public void SetUp() { _calculator = new RpnCalculator(); _calculator.Push(5); _calculator.Push(3); } [Test] public void Add_two_numbers() { Assert.That(_calculator.Add(), Is.EqualTo(8)); } [Test] public void Subtract_two_numbers() { Assert.That(_calculator.Subtract(), Is.EqualTo(2)); }
Repeat everything
[Test] public void Add_two_numbers() { var calculator = new RpnCalculator();
calculator.Push(5); calculator.Push(3); Assert.That(calculator.Add(), Is.EqualTo(8)); } [Test] public void Subtract_two_numbers() { var calculator = new RpnCalculator(); calculator.Push(5); calculator.Push(3); Assert.That(calculator.Subtract(), Is.EqualTo(2)); } [Test] public void Add_two_numbers() { var calculator = new RpnCalculator(); calculator.Push(5); calculator.Push(3); Assert.That(calculator.Add(), Is.EqualTo(8)); }
Separate mechanics from data
public void SetUp() { _calculator = new RpnCalculator(); } [Test]
public void Add_two_numbers() { _calculator.Push(5); _calculator.Push(3); Assert.That(_calculator.Add(), Is.EqualTo(8)); } private RpnCalculator _calculator; [SetUp] public void SetUp() { _calculator = new RpnCalculator(); } [Test] public void Add_two_numbers() { _calculator.Push(5); _calculator.Push(3); Assert.That(_calculator.Add(), Is.EqualTo(8)); } [Test] public void Subtract_two_numbers() { _calculator.Push(5); _calculator.Push(3); Assert.That(_calculator.Subtract(), Is.EqualTo(2)); }
If it isn’t data, it must be mechanics https://www.flickr.com/photos/sarahreido/3120877348
[Test] public void Show_result_of_an_addition_on_the_display() { var stubCalculatorEngine = Substitute.For<ICalculatorEngine>(); stubCalculatorEngine.Add(1,
2).Returns(3); var mockCalculatorDisplay = Substitute.For<ICalculatorDisplay>(); var calculator = new Calculator(stubCalculatorEngine, mockCalculatorDisplay); calculator.Type('1', '+', '2', '='); mockCalculatorDisplay.Received().Show("3"); }
[Test] public void Show_result_of_an_addition_on_the_display() { var stubCalculatorEngine = Substitute.For<ICalculatorEngine>(); stubCalculatorEngine.Add(1,
2).Returns(3); var mockCalculatorDisplay = Substitute.For<ICalculatorDisplay>(); var calculator = new Calculator(stubCalculatorEngine, mockCalculatorDisplay); calculator.Type('1', '+', '2', '='); mockCalculatorDisplay.Received().Show("3"); }
[SetUp] public void SetUp() { _stubCalculatorEngine = Substitute.For<ICalculatorEngine>(); _mockCalculatorDisplay =
Substitute.For<ICalculatorDisplay>(); _calculator = new Calculator(_stubCalculatorEngine, _mockCalculatorDisplay); } [Test] public void Show_result_of_an_addition_on_the_display() { _stubCalculatorEngine.Add(1, 2).Returns(3); _calculator.Type('1', '+', '2', '='); _mockCalculatorDisplay.Received().Show("3"); }
Keep only what is essential to understand the test
Thanks! Alex Tercete @alextercete https://speakerdeck.com/alextercete/writing-readable-tests