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
Building a testing culture
Search
Pedro Tavares
June 02, 2018
Programming
180
0
Share
Embed
Copy iframe code
Copy JS code
Copy link
Start on current slide
Building a testing culture
Pedro Tavares
June 02, 2018
More Decks by Pedro Tavares
See All by Pedro Tavares
Diving into Merkle Trees
ordepdev
2
860
Harvest, Yield, and Scalable Tolerant Systems
ordepdev
0
290
Things you should know about Database Storage and Retrieval
ordepdev
0
170
Building a testing culture
ordepdev
0
1.4k
Things you should know about Database Storage and Retrieval
ordepdev
0
1.7k
GitLab as an Application Lifecycle Management Suite
ordepdev
0
440
Consumer Driven Contracts
ordepdev
0
1.4k
Optional<Java>
ordepdev
0
1.4k
Microservices? You have to
ordepdev
0
1.3k
Other Decks in Programming
See All in Programming
バグを直したら useEffect が消えた
colorful12
3
670
Detecting Compromised CI with eBPF and Cilium Tetragon
lizrice
0
230
Building a Meta Ray-Ban display app
akkeylab
0
170
KotlinConf Extended South Korea 2026 Keynote
l2hyunwoo
0
120
Gmail/Google DriveをトリガーにAIエージェントを動かそう! / Run AI agents with Gmail/Google Drive as triggers!
har1101
2
360
170k Jobs a Day on GKE: Scaling Mercari's CI Platform - and What's Next for AI-Native Development
junyaokabe
0
120
まだ間に合う!今年の夏こそSchemeのマクロ展開器を完全理解!
omasanori
0
270
仕様駆動開発へのトライを機に チームに適合する手法を模索し続けている話
freee
PRO
0
590
Jindong: Introducing Declarative Haptics in Compose Multiplatform
l2hyunwoo
0
130
freeeにおけるEvalsの実践例の紹介
freee
PRO
0
140
夏だ!祭りだ!祭りとはドメインモデリングでは?
ryugen04
0
350
AI時代に設計が 最大の生産性レバーになる 意図駆動開発とデータを消さない設計|Don't Delete Your Data or Your Intent — Design as the Deepest Lever in the AI Era
tomohisa
1
1.1k
Featured
See All Featured
Information Architects: The Missing Link in Design Systems
soysaucechin
1
1.1k
RailsConf & Balkan Ruby 2019: The Past, Present, and Future of Rails at GitHub
eileencodes
141
35k
Into the Great Unknown - MozCon
thekraken
41
2.7k
HDC tutorial
michielstock
2
810
Avoiding the “Bad Training, Faster” Trap in the Age of AI
tmiket
0
210
StorybookのUI Testing Handbookを読んだ
zakiyama
31
6.9k
Embracing the Ebb and Flow
colly
88
5.1k
Testing 201, or: Great Expectations
jmmastey
46
8.2k
Raft: Consensus for Rubyists
vanstee
141
7.6k
Making the Leap to Tech Lead
cromwellryan
135
10k
What's in a price? How to price your products and services
michaelherold
247
13k
Leveraging LLMs for student feedback in introductory data science courses - posit::conf(2025)
minecr
1
350
Transcript
TESTING building CULTURE
https://ordepdev.me/posts/test-driven-developers
THIS IS NOT ABOUT TDD!
@ordepdev
First of all Why testing?
“It’s time for software developers to take up the mantle
of responsibility for what they produce.
Testing is the engineering rigour of software development.
Responsibility — the state or fact of being accountable or
to blame for something.
Rigour — the quality of being extremely thorough and careful.
Software Engineering
An engineering discipline that is concerned with all aspects of
software production.
MUCH MORE THAN CODING!
Types of Bad Software Projects
1. Without tests.
Zero Automated Tests.
ZERO!
Lack of professionalism?
Lack of skills?
Lack of knowledge?
Lack of time to test?
It can be all of them.
What about software quality?
Relax, we test all features with manual testing.
None
2. With Wrongly Designed Tests..
Testing is HARD.
https://twitter.com/codepipes/status/987934900111138816
Testing pitfalls: coupling.
Implementation Boundary Testing Boundary
Implementation Boundary Testing Boundary ✅ ✅ ✅ ✅ ✅ ✅
✅ ✅ ❌ ❌
Uncertainty and Doubt.
Implementation Boundary Testing Boundary ✅ ✅ ✅ ✅ ✅ ❌
❌ ❌ ❌ ❌
Testing pitfalls: performance.
Taking too much time? — that’s a no run.
Types of Testing
1. Testing after the implementation.
2. Testing during the implementation.
3. Testing that reproduce bugs.
It’s our job to build a testing culture!
But how?
5 rules.
1. Every change must have tests.
50 100 150 200 Development Unit Tests Functional Tests System
Tests Production The cost of bugs
Bugs in production are embarrassing and costly.
2. Write more than unit tests.
https://twitter.com/pwlporto/status/999258562370170880
We do not know how much an increase in coverage
can decrease the number of defects.” “
https://ordepdev.me/posts/code-coverage
Mutation testing!
def add(x,y) x + y end def add(x,y) x -
y end Source Code Mutation
Property-based testing! https://hypothesis.works/articles/quickcheck-in-every-language
http://blog.jessitron.com/2013/04/property-based-testing-what-is-it.html
Contract testing! https://martinfowler.com/bliki/ContractTest.html
https://ordepdev.me/posts/boost-your-confidence-with-consumer-driven-contracts
Model-based testing! http://mit.bme.hu/~micskeiz/pages/modelbased_testing.html
Instead of writing hundreds of test cases, write an abstract
model of the system and generate a set of test cases.” “
None
Formal methods! https://www.infoq.com/presentations/aws-testing-tla
Formal methods use mathematical proof as a complement to system
testing in order to ensure correct behavior.” “
3. Bug fixing must have tests.
Don’t repeat the same bug hunting — write a test!
4. Testing code must be reviewed.
A well-designed test suite is much easier to read, understand
and evolve.
Testing code is production code!
5. Test suites must be consistent.
L12. assertEquals(input, expectation); L35. assertEquals(expectation, input); L43. assertThat(input).isEqualTo( expectation); Assertions
L12. assertEquals(input, expectation); L35. assertEquals(expectation, input); L43. assertThat(input).isEqualTo( expectation); Assertions
L12. createEntity L35. create_withValidPayload_success L43. create_withValidPayload_shouldPersistEntity Test Methods
L12. createEntity L35. create_withValidPayload_success L43. create_withValidPayload_shouldPersistEntity Test Methods
We must share the same values, practices, and tools.
Enforce them through code reviews, static analysis, and style checking
tools.
5+1.Test suites must be visible.
A failed test is a failed build!
Wrapping up.
People who are successful at automating tasks tend to work
this way in every aspect of their jobs. It is just how they work; it is part of their culture. “ ”
Manual work is a bug. acmqueue | january-february 2018
ALWAYS BE AUTOMATING!
GO AND FIX YOUR BROKEN CULTURE!
TESTING building CULTURE @ordepdev ordepdev.me Thanks!