2 posts tagged with "testing"

While writing the previous post about our per-test SQLite databases, I was describing how each test gets its own in-memory database, no shared connections, no shared state. And I thought: wait, if nothing is shared, can we just run them all at the same time?

Turns out we could, and our server test suite went from ~4 seconds to ~0.85 seconds for around 800 tests. Zero code changes to the tests themselves. One 25-line Erlang module.

Curling IO's tests don't need a shared test database, cleanup hooks, or transaction tricks. Each test gets its own database, so a test can pass alone or in the full suite for the same reason: nothing else can touch its data.

That falls out of one Version 3 choice: SQLite runs in-process. Each test gets a completely independent in-memory SQLite database, cloned from a template in microseconds using SQLite's backup API.