fix(graph): stabilize debouncer tests with synctest fake clock #741

Merged
argoyle merged 1 commits from fix-flaky-debouncer-test into main 2026-02-25 12:49:13 +00:00
+18 -6
View File
@@ -3,6 +3,7 @@ package graph
import (
"sync/atomic"
"testing"
"testing/synctest"
"time"
"github.com/stretchr/testify/assert"
@@ -10,6 +11,7 @@ import (
)
func TestDebouncer_Coalesces(t *testing.T) {
synctest.Test(t, func(t *testing.T) {
d := NewDebouncer(50 * time.Millisecond)
var calls atomic.Int32
@@ -20,13 +22,16 @@ func TestDebouncer_Coalesces(t *testing.T) {
})
}
// Wait for the debounce delay plus some margin.
time.Sleep(150 * time.Millisecond)
// Advance fake clock past the debounce delay and let goroutines settle.
time.Sleep(50 * time.Millisecond)
synctest.Wait()
assert.Equal(t, int32(1), calls.Load(), "rapid calls should coalesce into a single execution")
})
}
func TestDebouncer_DifferentKeys(t *testing.T) {
synctest.Test(t, func(t *testing.T) {
d := NewDebouncer(50 * time.Millisecond)
var calls atomic.Int32
@@ -34,24 +39,31 @@ func TestDebouncer_DifferentKeys(t *testing.T) {
d.Debounce("key-b", func() { calls.Add(1) })
d.Debounce("key-c", func() { calls.Add(1) })
time.Sleep(150 * time.Millisecond)
time.Sleep(50 * time.Millisecond)
synctest.Wait()
assert.Equal(t, int32(3), calls.Load(), "different keys should fire independently")
})
}
func TestDebouncer_TimerReset(t *testing.T) {
synctest.Test(t, func(t *testing.T) {
d := NewDebouncer(100 * time.Millisecond)
var value atomic.Int32
// First call sets value to 1.
d.Debounce("key", func() { value.Store(1) })
// Wait 60ms (less than the 100ms delay), then replace with value 2.
// Advance 60ms (less than the 100ms delay) — first timer hasn't fired.
time.Sleep(60 * time.Millisecond)
// Replace with value 2 — resets the timer to fire at 60+100 = 160ms.
d.Debounce("key", func() { value.Store(2) })
// At 60ms the first timer hasn't fired yet. Wait for the second timer.
time.Sleep(150 * time.Millisecond)
// Advance another 100ms (total 160ms) to fire the reset timer.
time.Sleep(100 * time.Millisecond)
synctest.Wait()
require.Equal(t, int32(2), value.Load(), "later call should replace the earlier one")
})
}