Return the context's cancel cause in the Watcher

Signed-off-by: Tom Wieczorek <[email protected]>

pkg/kubernetes/watch/watcher.go

@@ -189,8 +189,9 @@ func (w *Watcher[T]) WithErrorCallback(callback ErrorCallback) *Watcher[T] {
 	return w
 }
 
-// Until runs a watch until condition returns true. It will error out in case
-// the context gets canceled or the condition returns an error.
+// Until runs a watch until condition returns true. It will return the error
+// returned by condition, nil if condition returns true, or the context's cause
+// in case the context gets cancelled, whichever happens first.
 func (w *Watcher[T]) Until(ctx context.Context, condition Condition[T]) error {
 	return retry(ctx, w.errorCallback, func(ctx context.Context) error {
 		ctx, cancel := context.WithCancel(ctx)
@@ -304,7 +305,7 @@ func (w *Watcher[T]) watch(ctx context.Context, resourceVersion string, conditio
 	for startWatch != nil {
 		select {
 		case <-ctx.Done():
-			return nil, ctx.Err()
+			return nil, context.Cause(ctx)
 
 		case <-watchTimeout.C:
 			return nil, apierrors.NewTimeoutError("server unexpectedly didn't close the watch", 1)
@@ -422,7 +423,7 @@ func retry(ctx context.Context, errorCallback ErrorCallback, runWatch func(conte
 			select {
 			case <-ctx.Done():
 				timer.Stop()
-				return ctx.Err()
+				return context.Cause(ctx)
 			case <-timer.C:
 				continue
 			}