Utils.build_nested_query to handle empty arrays and hashes

[IvanUkhov]

Hello,

In master we have the following:

Rack::Utils.build_nested_query('foo' => 'bar', 'baz' => []) #=> "foo=bar&"
Rack::Utils.build_nested_query('foo' => 'bar', 'baz' => {}) #=> "foo=bar&"

The pull request turns it into:

Rack::Utils.build_nested_query('foo' => 'bar', 'baz' => []) #=> "foo=bar"
Rack::Utils.build_nested_query('foo' => 'bar', 'baz' => {}) #=> "foo=bar"

Regards,
Ivan

[mikegee]

Does this fix something that is broken or does it just make the url look a little better?

[IvanUkhov]

@mikegee, although there are rather mild restrictions on the format of a query string in general, it is very specific in certain contexts. For example, according to the W3C, a query string of a form is a set of pairs separated by the ampersand, and each pair is composed of a key and a value separated by the equals sign. Therefore, if we split foo=bar& by the ampersand, the second pair will be invalid.

I believe that most of the parser nowadays will not have any problems with foo=bar&; I just consider it to be a kind of pollution, and I want the Internet to be clean.

Regards,
Ivan