if got := srcsetFilterAndEscaper(test.input); got != test.want {
			t.Errorf("%s: srcsetFilterAndEscaper(%q) want %q != %q", test.name, test.input, test.want, got)
		}
	}
}

func BenchmarkURLEscaper(b *testing.B) {
	for i := 0; i < b.N; i++ {
		urlEscaper("http://example.com:80/foo?q=bar%20&baz=x+y#frag")
	}
}

func BenchmarkURLEscaperNoSpecials(b *testing.B) {
	for i := 0; i < b.N; i++ {