blockingtest

What it detects

Reports blocking channel receives and selects in test code when they have no cancellation or timer escape. It also reports unguarded sends in context-aware test helpers.

Checks

Check	What it detects
send*	Reports unguarded channel sends in context-aware test code.
receive*	Reports blocking channel receives in tests without a cancellation escape.
select*	Reports blocking selects in tests without a cancellation escape.

* Opt-in; requires explicit selection.

Why this is flagged

An unconditional wait can leave a test stuck forever when the expected event never happens. A cancellation or timeout path lets the test stop promptly and report a useful failure instead of hanging the entire test run.

Further reading: Go concurrency patterns: Pipelines and cancellation, Timing out, moving on.

How to fix it

Wait with a select that also listens for the test context or a bounded timeout. If cancellation wins, stop the test with a message that explains what it was waiting for.

Examples

Flagged code

func waitForEvent(t *testing.T, events <-chan Event) Event {
  // gohawk: blocking channel receive in test code requires cancellation-aware select
  return <-events
}

Accepted code

func waitForEventSafely(t *testing.T, events <-chan Event) Event {
  t.Helper()
  select {
  case event := <-events:
    return event
  case <-t.Context().Done():
    t.Fatal("timed out waiting for event")
    return Event{}
  }
}