How to compare two methods?

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
35/100
Issue type
Bug
Clarity
Needs clarification
Activity status
Stale
Tech stack
javascript, python
Domain
compilers

Research direction

No source file or test is named. Start by reproducing the provided ClassA callback-comparison example and inspect the generated JavaScript shown in the issue. Done means determining whether the differing method identity is expected or a compiler bug, then establishing a concrete workaround or regression coverage.

Written by the indexing model from the issue text.

Description

IS: limitation IS: question

Hi.

I want to check whether a given callback is a specific method in a class. I found that comparing two methods failed. Following is the test code:

class ClassA:
    def proc(self, callback=None):
        if callback==self.method1:
            print('callback==self.method1, callback=', callback)
        else:
            print('callback!=self.method1')
            print('callback.name=', callback.name)
            print('callback.__name__=', callback.__name__)
            print('callback.__qualname__=', callback.__qualname__)
            print('callback=',  callback)
            print('self.method1=', self.method1)
        if self.method1==self.method1:
            print('self.method1==self.method1')
        else: print('self.method1!=self.method1')
    def method1(self):
        pass
def main():
    a1= ClassA()
    a1.proc(a1.method1)
if __name__ == '__main__':
    main()

output:

callback!=self.method1
callback.name= None
callback.__name__= None
callback.__qualname__= None
callback= function () {
                var args = [] .slice.apply (arguments);
                return func.apply (null, [self] .concat (args));
            }
self.method1= function () {
                var args = [] .slice.apply (arguments);
                return func.apply (null, [self] .concat (args));
            }
self.method1!=self.method1

What I was surprised was the last line in the output, self.method1!=self.method1, which was a self comparison, but failed. (Is it a bug?)

How can I know a given callback is equal to a specific method? I tried to find a workaround. But as the output above, information about the method (name, _ _ name _ _, and _ _ qualname _ _) is not available. Any idea or workaround is welcome if you have any.

Thanks.

Dominant language
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