Issue #11064 has been reported by Jan Lelis.

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Bug #11064: #singleton_methods for objects with special singleton_class returns an empty array
https://bugs.ruby-lang.org/issues/11064

* Author: Jan Lelis
* Status: Open
* Priority: Normal
* Assignee: 
* ruby -v: ruby 2.2.1p85 (2015-02-26 revision 49769) [x86_64-linux]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN
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~~~
def nil.bla
  42  
end

# works
nil.bla #=> 42
nil.singleton_method(:bla) #=> #<Method: NilClass#bla>
NilClass.instance_methods.include? :bla #=> true

# does not work
nil.singleton_methods #=> []
~~~




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