Tests as docs? 🤔
Tests can serve as documentation. But the default `mix test` command doesn't print them out in a way that has clear information. Thankfully, there are two flags that can make it really nice.
testing 🏷️
How to find the 🐢 slowest N modules in test suite
If you want to improve your test suite speed, the first thing we want to do is find out what's the slowest module we have, right? Elixir 1.17's got your back.
🔍 ExUnit 1.17's new flag to find intermittent failures
Intermittent tests are a pain, but Elixir 1.17 has a really cool new flag in `mix test` to help us.
😲 Test breakpoints? New in Elixir 1.17 ✨
Elixir 1.17 shipped with a new feature that lets us put breakpoints right into our tests! All we have to do is run them with --breakpoints. Too good to be true? Check it out!
ExUnit's --seed surprising behavior! 😲
If I asked you what ExUnit’s `--seed` option does, you'd probably say 'randomize the order of tests', right? And that's right. But it turns out it does more!
Easy, Concurrent Temp Dirs with ExUnit ✅
What do you do when you want a temp directory in your tests? ExUnit's got your back with one simple trick!
🔍 Debug Ecto queries in tests
Sometimes, it's helpful to see what queries our tests are making. There's a quick config change to do that!
Elixir 1.16 running multiple tests with line numbers! ✅
Prior to Elixir 1.16 we couldn't run multiple test files with their line numbers. With Elixir 1.16, we can!
Testing Async Assigns (Preview)
With LiveView's new async assigns, we can now load data asynchronously like a breeze. But how do we test it since we have async behavior? 🤔
ExUnit. It's an app!
I imagine many think ExUnit just does some type of scripting to run tests. But it’s a full Elixir app! Check it out.
Anatomy of a LiveView Test
The best way to write LiveView tests: follow the familiar setup-exercise-verify testing pattern
Inspecting LiveView tests with open_browser/2
Anytime I need to inspect a page when testing LiveView, I reach for `open_browser/2`.
Better Phoenix function components tests with ~H sigil
There are 2 ways to test Phoenix function components. But I recommend only using one of them!
Using ExUnit's test context for unique values
Sometimes we need unique values in our tests. There's a nice ExUnit trick we can use.
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