This allows RDoc to better generate documentation for methods
following the Ruby core documentation guide (which omits aliases
in call-seq in most cases).  This makes documentation for methods
defined in C more similar to methods defined in Ruby.  For methods
defined in Ruby, the method description of the aliased method is
already not used (you have to explicitly document the alias to
use it).

Internally, this adds AnyMethod#has_call_seq? and #skip_description?,
and updates Darkfish to:

* only show the method name if there is a call-seq for the method,
  but the call-seq omits the method
* to omit the method description if the method is an alias or has
  aliases and has a call-seq that does not include the method

See discussion in https://github.com/ruby/ruby/pull/7316 for
details.

https://github.com/ruby/rdoc/commit/e3688de49b

deduplicate_call_seq has a bug that skips call-seq for methods where the
alias is a prefix of the method name. For example, if the alias name is
"each" and the current method name is "each_line", then
deduplicate_call_seq will skip all call-seq for "each_line" since it
will believe that it is for the alias.

https://github.com/ruby/rdoc/commit/1148988ccc

This change fixes alias call-seq to return nil if the method's
call-seq does not specify the alias.

Previously, the alias's call-seq would be an empty string in this case
which broke darkfish rendering.

This change also backfills test coverage for 0ead786 which moved
call-seq deduplication into AnyMethod.

https://github.com/ruby/rdoc/commit/5ce2789b6f

https://github.com/ruby/rdoc/commit/45c92005fe

Previously, only calls to rb_define_alias were treated as aliases.
This treats calls to rb_define_method with the same C function as
aliases, with the first function defined being the primary method.

This move the dedup code from the C parser to AnyMethod, and has
AnyMethod look in its aliases to find the call_seq.

Switch the deduplication code to remove lines matching one of the
other aliases, instead of only keeping lines matching the current
alias.  The previous approach could eliminate all call_seq lines
in cases where no line matched.  This was necessary to pass
tests when call_seq does deduplication by default.

The only change to the darkfish template is to not perform
unnecessary work by deduplicating twice.

https://github.com/ruby/rdoc/commit/0ead78616b

  It version applied `frozen_string_literal: true`

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@60920 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

  * It version introduced did you mean? feature for ri command:
    https://github.com/ruby/rdoc/pull/533
  * Removed obbsoleted ruby_token.rbb.
    [Bug #13990][ruby-core:83180]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@60146 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

When you change this to true, you may need to add more tests.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@53141 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@47391 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

  RDoc 4.1.0 contains a number of enhancements including a new default
  style and accessibility support.  You can see the changelog here:

  https://github.com/rdoc/rdoc/blob/v4.1.0.preview.1/History.rdoc

* test/rdoc:  ditto.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@42971 b2dd03c8-39d4-4d8f-98ff-823fe69b080e