wakey wakey

wake_detector_test.go

@@ -0,0 +1,67 @@
+package nebula
+
+import (
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestWakeDetector(t *testing.T) {
+	delta := time.Duration(0)
+	ok := true
+	w := &wakeDetector{read: func() (time.Duration, bool) { return delta, ok }}
+
+	// The first sample primes the baseline and never reports a wake, even with a pre-existing spread
+	delta = 3 * time.Hour
+	slept, sok := w.Sample()
+	assert.True(t, sok)
+	assert.Equal(t, time.Duration(0), slept)
+
+	// A stable spread means the machine never slept
+	slept, sok = w.Sample()
+	assert.True(t, sok)
+	assert.Equal(t, time.Duration(0), slept)
+
+	// The spread grows by exactly the time spent suspended
+	delta += 42 * time.Second
+	slept, sok = w.Sample()
+	assert.True(t, sok)
+	assert.Equal(t, 42*time.Second, slept)
+
+	// A wake is reported once, then the baseline moves with it
+	slept, sok = w.Sample()
+	assert.True(t, sok)
+	assert.Equal(t, time.Duration(0), slept)
+
+	// Negative jitter from the non-atomic clock pair reads clamps to zero
+	delta -= time.Microsecond
+	slept, sok = w.Sample()
+	assert.True(t, sok)
+	assert.Equal(t, time.Duration(0), slept)
+
+	// Consecutive suspends both report; the clamped jitter moved the baseline so it is not double-counted
+	delta += time.Minute
+	slept, _ = w.Sample()
+	assert.Equal(t, time.Minute, slept)
+	delta += time.Hour
+	slept, _ = w.Sample()
+	assert.Equal(t, time.Hour, slept)
+
+	// An unsupported platform read reports not-ok
+	ok = false
+	_, sok = w.Sample()
+	assert.False(t, sok)
+}
+
+// TestWakeDetectorPlatformClock smoke tests the real clock pair: two samples close together must not report a
+// wake on a machine that isn't suspending mid-test.
+func TestWakeDetectorPlatformClock(t *testing.T) {
+	w := newWakeDetector()
+	if _, ok := w.Sample(); !ok {
+		t.Skip("platform has no suspend clock pair")
+	}
+	slept, ok := w.Sample()
+	assert.True(t, ok)
+	assert.Less(t, slept, time.Second)
+}