}
				t.Logf("read(%d) = %q, %v", len(p), string(p[:n]), err)
			}
			want("abc", nil)
			want("", nil)
			want("def", nil)
			want("", io.EOF)
		})
	}
}

func TestReaderReset(t *testing.T) {
	checkAll := func(r *Reader, want string) {
		t.Helper()
		all, err := io.ReadAll(r)
		if err != nil {
			t.Fatal(err)
		}
		if string(all) != want {