idx+1, tt.whence, tt.offset, gotOff, gotErr, tt.returnOff)
			}
		}
	})
}

func TestOffsetWriter_WriteAt(t *testing.T) {
	const content = "0123456789ABCDEF"
	contentSize := int64(len(content))
	tmpdir, err := os.MkdirTemp(t.TempDir(), "TestOffsetWriter_WriteAt")
	if err != nil {
		t.Fatal(err)
	}

	work := func(off, at int64) {
		position := fmt.Sprintf("off_%d_at_%d", off, at)