Bug #11188: Method#inspect for chaining alias methods

• Status: Closed
• Assignee: matz (Yukihiro Matsumoto)
• Target version: -
• ruby -v: 2.3dev
• Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN
• Tags: core, patch

[ko1 (Koichi Sasada)]

The following script prints strange results (at least for me).

class C0
  def foo
  end
end

class C1 < C0
  alias foo1 foo
  alias foo2 foo1
  alias foo3 foo2
end

p C1.new.method(:foo)
p C1.new.method(:foo1)
p C1.new.method(:foo2)
p C1.new.method(:foo3)

Result:

#<Method: C1(C0)#foo>
#<Method: C1(C0)#foo1(foo)>
#<Method: C1#foo2(foo)>
#<Method: C1#foo3(foo)>

I believe 3rd and 4th results should be:

#<Method: C1(C0)#foo2(foo)>
#<Method: C1(C0)#foo3(foo)>

How about it?

[jeremyevans0 (Jeremy Evans)]

• File method-inspect-chain-alias-11188.patch method-inspect-chain-alias-11188.patch added

I agree with ko1's opinion. Attached is a patch that implements his proposal.

Note that this change cannot be made in method_inspect, because at that time, the necessary information has already been lost. To implement ko1's proposal, changes to rb_alias are required, so that the defined_class in the alias chain methods (foo2 and foo3) is set correctly to C0.

[jeremyevans0 (Jeremy Evans)]

• Status changed from Open to Closed

This patch was merged in adecd43197d5ea2a62a618a5c9be653bcf009c62.

[Eregon (Benoit Daloze)]

Nice, in fact this was already the behavior in TruffleRuby and JRuby.