Chore: use generics as possible

common/picker/picker_test.go

@@ -8,33 +8,38 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
-func sleepAndSend(ctx context.Context, delay int, input any) func() (any, error) {
-	return func() (any, error) {
+func sleepAndSend[T any](ctx context.Context, delay int, input T) func() (T, error) {
+	return func() (T, error) {
 		timer := time.NewTimer(time.Millisecond * time.Duration(delay))
 		select {
 		case <-timer.C:
 			return input, nil
 		case <-ctx.Done():
-			return nil, ctx.Err()
+			return getZero[T](), ctx.Err()
 		}
 	}
 }
 
 func TestPicker_Basic(t *testing.T) {
-	picker, ctx := WithContext(context.Background())
+	picker, ctx := WithContext[int](context.Background())
 	picker.Go(sleepAndSend(ctx, 30, 2))
 	picker.Go(sleepAndSend(ctx, 20, 1))
 
 	number := picker.Wait()
 	assert.NotNil(t, number)
-	assert.Equal(t, number.(int), 1)
+	assert.Equal(t, number, 1)
 }
 
 func TestPicker_Timeout(t *testing.T) {
-	picker, ctx := WithTimeout(context.Background(), time.Millisecond*5)
+	picker, ctx := WithTimeout[int](context.Background(), time.Millisecond*5)
 	picker.Go(sleepAndSend(ctx, 20, 1))
 
 	number := picker.Wait()
-	assert.Nil(t, number)
+	assert.Equal(t, number, getZero[int]())
 	assert.NotNil(t, picker.Error())
 }
+
+func getZero[T any]() T {
+	var result T
+	return result
+}