| 1 | package shutdown |
| 2 | |
| 3 | import ( |
| 4 | "sync/atomic" |
| 5 | "testing" |
| 6 | "time" |
| 7 | ) |
| 8 | |
| 9 | // resetForTest clears the package-level state. Tests in this file mutate |
| 10 | // global state, so they cannot run in parallel. |
| 11 | func resetForTest(t *testing.T) { |
| 12 | t.Helper() |
| 13 | startedAt.Store(0) |
| 14 | } |
| 15 | |
| 16 | func TestInProgressInitiallyFalse(t *testing.T) { |
| 17 | resetForTest(t) |
| 18 | if InProgress() { |
| 19 | t.Fatal("InProgress() should be false before MarkStarted") |
| 20 | } |
| 21 | if !StartedAt().IsZero() { |
| 22 | t.Fatal("StartedAt() should be zero time before MarkStarted") |
| 23 | } |
| 24 | } |
| 25 | |
| 26 | func TestMarkStartedFirstCallWins(t *testing.T) { |
| 27 | resetForTest(t) |
| 28 | if !MarkStarted() { |
| 29 | t.Fatal("first MarkStarted() should return true") |
| 30 | } |
| 31 | if MarkStarted() { |
| 32 | t.Fatal("second MarkStarted() should return false") |
| 33 | } |
| 34 | if !InProgress() { |
| 35 | t.Fatal("InProgress() should be true after MarkStarted") |
| 36 | } |
| 37 | if StartedAt().IsZero() { |
| 38 | t.Fatal("StartedAt() should be non-zero after MarkStarted") |
| 39 | } |
| 40 | } |
| 41 | |
| 42 | func TestMarkStartedPreservesFirstTimestamp(t *testing.T) { |
| 43 | resetForTest(t) |
| 44 | MarkStarted() |
| 45 | first := StartedAt() |
| 46 | // Sleep is intentional: it forces time.Now() to advance between the |
| 47 | // two MarkStarted calls so a regression that replaces the CAS with a |
| 48 | // plain Store would change StartedAt() and fail the assertion below. |
| 49 | // Without the gap, both calls could land in the same nanosecond on |
| 50 | // coarse-resolution clocks and mask the bug. |
| 51 | time.Sleep(2 * time.Millisecond) |
| 52 | MarkStarted() // second call must not overwrite |
| 53 | if !StartedAt().Equal(first) { |
| 54 | t.Fatalf("StartedAt() changed after second MarkStarted: %v != %v", StartedAt(), first) |
| 55 | } |
| 56 | } |
| 57 | |
| 58 | func TestMarkStartedConcurrent(t *testing.T) { |
| 59 | resetForTest(t) |
| 60 | const goroutines = 64 |
| 61 | var winners atomic.Int32 |
| 62 | done := make(chan struct{}) |
| 63 | for range goroutines { |
| 64 | go func() { |
| 65 | if MarkStarted() { |
| 66 | winners.Add(1) |
| 67 | } |
| 68 | done <- struct{}{} |
| 69 | }() |
| 70 | } |
| 71 | for range goroutines { |
| 72 | <-done |
| 73 | } |
| 74 | if got := winners.Load(); got != 1 { |
| 75 | t.Fatalf("expected exactly 1 winner across %d goroutines, got %d", goroutines, got) |
| 76 | } |
| 77 | } |