(examples-for percent-encode
("escapes space"
(percent-encode "x y")
"x%20y")
("escapes <>"
(percent-encode "x<y>")
"x%3Cy%3E")
("escapes []"
(percent-encode "x[y]")
"x%5By%5D")
("escapes %"
(percent-encode "%50")
"%2550")
("does not escape -"
(percent-encode "a-b")
"a-b")
("escapes a bunch of stuff in the same string"
(percent-encode "x[y?]=a&b%c/d")
"x%5By%3F%5D=a&b%25c%2Fd"))