}
		got := commonPath(pat1, pat2)
		if got != test.want {
			t.Errorf("%s vs. %s: got %q, want %q", test.p1, test.p2, got, test.want)
		}
	}
}

func TestDifferencePath(t *testing.T) {
	for _, test := range []struct {
		p1, p2 string
		want   string
	}{
		{"/a/{x}", "/{x}/a", "/a/x"},
		{"/{x}/a", "/a/{x}", "/x/a"},
		{"/a/{z}/", "/{z}/a/", "/a/z/"},