♻️ (sum_tail): refactor sum_tail

Author: yuanyu90221

arrays-and-slices/sum_test.go

@@ -49,19 +49,20 @@ func TestSumAll(t *testing.T) {
 }
 
 func TestSumAllTails(t *testing.T) {
-	t.Run("make the sums of some slices", func(t *testing.T) {
-		got := SumAllTails([]int{1, 2}, []int{0, 9})
-		want := []int{2, 9}
-
+	checkSums := func(t testing.TB, got, want []int) {
+		t.Helper()
 		if !reflect.DeepEqual(got, want) {
 			t.Errorf("got %v, want %v", got, want)
 		}
+	}
+	t.Run("make the sums of some slices", func(t *testing.T) {
+		got := SumAllTails([]int{1, 2}, []int{0, 9})
+		want := []int{2, 9}
+		checkSums(t, got, want)
 	})
 	t.Run("safely sum empty slices", func(t *testing.T) {
 		got := SumAllTails([]int{}, []int{3, 4, 5})
 		want := []int{0, 9}
-		if !reflect.DeepEqual(got, want) {
-			t.Errorf("got %v, want %v", got, want)
-		}
+		checkSums(t, got, want)
 	})
 }