https://github.com/ruby/uri/commit/77241d6508

https://github.com/ruby/uri/commit/898b889811

We use the following site for that now:

* https://tools.ietf.org/ or http
* https://datatracker.ietf.org or http

Today, IETF said the official site of RFC is www.rfc-editor.org.

FYI: https://authors.ietf.org/en/references-in-rfcxml

I replaced them to www.rfc-editor.org.

https://github.com/ruby/uri/commit/feb8e0dd73

Otherwise, the path could be considered part of the host or port.

This is better than modifying the path to make it absolute when
a host or port is set.  We could also raise for invalid paths
when a host or port is set using check_path, but that results
in weird errors, and won't catch issues (such as ftp allowing a
relative path).

Fixes [Bug #19916]

https://github.com/ruby/uri/commit/ac32aa005b

URI::Generic#{user,password} return the encoded values, which are
not that useful if you want to do authentication with them.
Automatic decoding by default would break backwards compatibility.
Optional automatic decoding via a keyword to URI.parse would
require threading the option through at least 3 other methods, and
would make semantics confusing (user= takes encoded or unencoded
password?) or require more work.  Thus, adding this as a separate
method seemed the simplest approach.

Unfortunately, URI lacks a method for correct decoding.  Unlike in
www form components, + in earlier parts of the URI such as the
userinfo section is treated verbatim and not as an encoded space.
Add URI.#{en,de}code_uri_component methods, which are almost the
same as URI.#{en,de}code_www_form_component, but without the
special SP => + handling.

Implements [Feature #9045]

https://github.com/ruby/uri/commit/16cfc4e92f

https://github.com/ruby/uri/commit/3b7ccfd835