SLIDESMANIA.COM SLIDESMANIA.COM Testing to avoid doubting 

SLIDESMANIA.COM Benjamin Cavy 

SLIDESMANIA.COM SLIDESMANIA.COM Testing to almost avoid doubting This could have been called 

SLIDESMANIA.COM SLIDESMANIA.COM Testing for a little less doubting This should have been called 

SLIDESMANIA.COM SLIDESMANIA.COM Disclaimer Opinions are my own they sometimes change I’m interested by yours ! 

SLIDESMANIA.COM SLIDESMANIA.COM This is not a « silver bullet » 

SLIDESMANIA.COM SLIDESMANIA.COM What is a good test anyway ? 

SLIDESMANIA.COM SLIDESMANIA.COM Tests pyramid Units Integration E2E Cost Execution time Precision 

SLIDESMANIA.COM SLIDESMANIA.COM My dream test 🎯 fails only when it should 🧪 is reproductible ⏩ runs quickly 💡is easy to understand 

SLIDESMANIA.COM SLIDESMANIA.COM Test pyramid Units Integration E2E 🧪 🧪 🧪 ⏩ ⏩ ⏩ 🧪 ⏩ 🧪 🧪 🧪 ⏩ ⏩ Not reproductible 

SLIDESMANIA.COM SLIDESMANIA.COM Unit tests shortcomings 🪢 Tighten coupling with code structure ⛓ Make refactoring harder 🧩 Testing pieces of code, not application features 😨 I got little faith in unit tests 

SLIDESMANIA.COM SLIDESMANIA.COM Testing diamong Integration E2E Units 

SLIDESMANIA.COM SLIDESMANIA.COM Integration tests : my guidelines 🧑💻 Focus on features / user journey 📦 Test in black box mode 🍾 Mock only what’s strictly necessary 

SLIDESMANIA.COM SLIDESMANIA.COM And concretly ? 

SLIDESMANIA.COM SLIDESMANIA.COM Test containers Containers orchestrated by your tests 🪩 Java, node, python, go, rust, … 🪞 « ISO prod » technical environnement 

SLIDESMANIA.COM SLIDESMANIA.COM Wiremock Stubs for HTTP cakks 🍾 Fine grain stubbing ⚙ Standalone server ✅ Call check Alternatives oMock-server (node) oMock Service Worker (frontend) 

SLIDESMANIA.COM SLIDESMANIA.COM Cypress Fast, easy and reliable tes:ng for anything that runs in a browser. 🎇 An UI that allows to clearly visualise all test steps 🧰 naviga9on, stubbing, and async asser9on features 🔎 4 supported browsers 

SLIDESMANIA.COM SLIDESMANIA.COM Testing library Accessibility oriented library 

SLIDESMANIA.COM SLIDESMANIA.COM Application API Application API Application API Frontend DOM 

SLIDESMANIA.COM SLIDESMANIA.COM Application API API API Frontend DOM 

SLIDESMANIA.COM SLIDESMANIA.COM Application API API API 

SLIDESMANIA.COM SLIDESMANIA.COM API API Application Frontend Application API DOM 

SLIDESMANIA.COM SLIDESMANIA.COM Pros 💥 Failure : behaviour has changed 🔧 Refactoring resilient ✅ Test the whole stack (SQL queries, …) 💡 Allow to imagine features from user perspective 

SLIDESMANIA.COM SLIDESMANIA.COM Pain points 🛠 Stubbs are hard to maintain 🐌 Things can get slow 🤯 Test code may become hard to read 

SLIDESMANIA.COM Total decoupling Reboot / complete reset between tests It’s slow !!! 2 main causes 🚚 Technical elements instantation 📑 Functionnal setup String coupling Context is kept between tests ⚠ Dependant of execution order Coupling « happy medium » Programmatic cleaning Common setup for a whole test suite 

SLIDESMANIA.COM SLIDESMANIA.COM My tests are too complicated ! 🔧 Extract « test primitives » 

SLIDESMANIA.COM SLIDESMANIA.COM My tests are too complicated ! 🔧 Extract « test primiBves » 🛠 FuncBonnal builders 

SLIDESMANIA.COM SLIDESMANIA.COM My tests are too complicated ! 🔧 Extract « test primiBves » 🛠 FuncBonnal builders 🚆Focus on one target in each test 

SLIDESMANIA.COM SLIDESMANIA.COM @benjamin_cavy Thank you ! Any question ?