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The suite that only fails on CI

Shared state, a static context and a blocking .Result. Make every test independent.

Advanced22 min on the clock5 graded checks · 100 pointsTesting an ASP.NET Core APIPro

Graded by reading your code against the checklist below.

What you build

Give every test its own database rather than one shared store
Remove the static shared context
Set up and tear down with IAsyncLifetime
Await the async calls instead of blocking on them
Add a second test that proves the first one’s rows are not visible to it

Done means

No shared state, a unique store per test, async throughout, and two tests that cannot see each other.

How it is graded

Published in full, before you start — every point is one of these and there is nothing else.

Every test gets its own database+25Tests that do not depend on each other
The static shared context is gone+20Tests that do not depend on each other
Setup and teardown use IAsyncLifetime+20Tests that do not depend on each other
Async calls are awaited, not blocked on+20async and await
A second test proves the isolation holds+15Tests that do not depend on each other

What it teaches

Tests that do not depend on each otheradvanced

xUnit runs classes in parallel, so one shared static context means two tests writing to the same store — the suite that passes locally and fails on CI, non-deterministically.

async and awaitbeginner

Calling .Result on a task blocks a thread that could have served another request, and under load that is the deadlock everyone has a story about — await is how you wait without holding anything up.

The rest of Testing an ASP.NET Core API

Your first xUnit testBeginner · 12 min Five tests, one behaviourBeginner · 12 min Stop calling the real thingIntermediate · 18 min The whole pipeline, in memoryIntermediate · 20 min The paths nobody testsIntermediate · 18 min