Overhaul test.CreateTestDb to use testing.T idioms

[xmtp-coder-agent]

Resolves #74

Summary

• test/helpers.go: CreateTestDb now accepts *testing.T, uses t.Context() for context, registers cleanup via t.Cleanup(), and calls t.Fatal() on migration errors. Returns only *bun.DB.
• All callers updated: Replaced db, cleanup := test.CreateTestDb() / defer cleanup() with db := test.CreateTestDb(t) across installations_test.go, subscriptions_test.go, and listener_test.go.
• Fixed Test_Get: Previously had cleanup commented out — now handled automatically by t.Cleanup.

Test plan

• go vet ./... passes (verified locally)
• go test -p 1 ./... passes with Docker services running
• All existing test behavior is preserved — cleanup now runs automatically via t.Cleanup

🤖 Generated with Claude Code

Note

Overhaul test.CreateTestDb to use testing.T idioms

• Changes CreateTestDb signature from () (*bun.DB, func()) to (t *testing.T) *bun.DB in test/helpers.go, eliminating the manual cleanup return value.
• The helper now uses t.Cleanup to truncate DB tables automatically and calls t.Fatal if migration fails, rather than silently ignoring errors.
• All callers in installations_test.go, subscriptions_test.go, and listener_test.go are updated to drop their defer cleanup() calls.
• Behavioral Change: migration errors now immediately fail the test instead of being silently ignored.

^{Macroscope summarized bc8539c.}

[neekolas]

Can you double check that t.Context() isn't available in cleanup scripts? Point me to the relevant docs.

[xmtp-coder-agent]

Re: comment — Yes, confirmed. t.Context() is intentionally cancelled before cleanup functions run. From the official docs:

Context returns a context that is canceled just before Cleanup-registered functions are called.

This is also in the Go 1.24 release notes:

The new T.Context and B.Context methods return a context that's canceled after the test completes and before test cleanup functions run.

The CI failure confirmed this — all four TRUNCATE TABLE queries failed with context canceled, causing data to leak between tests (Test_UnsubscribeResubscribe saw 4 rows instead of 1).

Using context.Background() in the cleanup function is the correct approach here.