Equality operator not implemented on Requirement

[lkollar]

Reproducer:

>>> packaging.requirements.Requirement("a") == packaging.requirements.Requirement("a")
False

Is this expected behaviour?

[brettcannon]

There's no comparison operator implemented on the class, so this may be on purpose. What's your specific use-case for wanting this? I ask because without a concrete version specifier of what's installed this is a very ephemeral thing.

And as a work-around, you could compare the string representations of the objects.

[lkollar]

I was trying to do this in a test and was wondering why it doesn't have it implemented. I ended up working it around with the string comparison, just like you suggested.

I opened the issue mainly to clarify if this is an omission or if there is a good reason for not having it implemented. I don't have a strong opinion here. My only data point is that 'pkg_resources.Requirement' implements it, but I'm not even sure it's a goal at all to attempt any sort of compatibility with it.

[brettcannon]

I don't know the history of the module to know if compatibility is in any way a goal.

[sbidoul]

I also stumbled on this requirement in a testing context. It would be nice to have.

[8day]

Comparison will require normalization of "dist; (((extra == 'doc')) and python_version == '3.8.6')" and "dist; 'doc' in extra and '3.8.6' in python_version" to "dist; python_version == '3.8.6' and extra == 'doc'", which requires a lot of work.

Also, considering that variable extra from environment markers is likely to be redefined in the near future, as discussed at https://discuss.python.org/t/the-extra-environment-marker-and-its-operators/, support for equality operator most likely will be added after such discussion will result in some PEP.

P.S. I am in no way related to PyPA, so these are just my two cents.

[pelson]

I was about to roll my sleeves up and implement this, when I saw that it has already been implemented in #499.

As a result of this:

>>> from packaging.requirements import Requirement

>>> Requirement('a==1') == Requirement('a== 1')"
True

And specifically, the motivating reproducer in the issues description is also working:

>>> import packaging.requirements 
>>> packaging.requirements.Requirement("a") == packaging.requirements.Requirement("a")
True

Therefore, suggest this can be closed.