net/url: url.Parse("example.com/oid/[order_id]") escapes [ ] in String() method #5684
Description
RFC 3986 specifies that reserved characters in URL paths should not be escaped, and
shouldEscape() is designed to enforce that.
The RFC specifies the following set as reserved:
gen-delims: ":", "/", "?", "#", "[",
"]", "@"
sub-delims: "!", "$", "&", "'",
"(", ")", "*", "+", ",",
";", "="
shouldEscape() only checks the following subset, and escapes the rest:
'$', '&', '+', ',', '/', ':', ';', '=', '?', '@'
When proxying, "http://example.com/oid/[order_id]", the "[" and
"]" get escaped, which is a bug. Servers may well handle
".../oid/[order_id]" and ".../oid/%5Border_id%5D" differently.
Example below:
http://play.golang.org/p/Vczuon9WR-