Undef problematic Object methods

[bf4]

Needs tests and references to issues

[mention-bot]

@bf4, thanks for your PR! By analyzing the history of the files in this pull request, we identified @beauby, @NullVoxPopuli and @bolshakov to be potential reviewers.

[idoa01]

resurfacing an old issue which I think can be solved here: #2002

[bf4]

@idoa01 not sure I follow

[idoa01]

Oh, sorry, I thought that I didn't comment in the end :(
(I didn't want to comment since I didn't check if the bug is still active in the latest release, but I see that the code is still there)

There is an old bug that I think can be addressed in the same manner - you can't have an attribute named hash since your code checks if the object respond_to? the attribute. with basic ruby objects method names, respond_to will always be true.

my bug originated with the display attribute that this pull request handles, but doesn't handle other methods like hash (see example in #2002)

you might be able to fix this with undef_method like in this pull request (but it's a more complicated issue, since undefing the .hash method might cause issues with equality)

a better solution would be to ignore all Object methods, something in the lines of:

if respond_to?(attr) && method(attr).owner != Kernel
  send(attr)
else
  object.read_attribute_for_serialization(attr)
end