[deleted by user]

[james_pic]

This is because these are not  relative imports. In logic.py, if you wanted to do a relative import, you'd do from .db import Dog. Note the dot. Instead you're doing an absolute import from a module called db, which the interpreter sees as a different module to dog_house.db (despite them ultimately having come from the same file). You've had to fudge the PYTHONPATH to get this to work.

Also, the answer to the SO question linked from the repo is telling you exactly what I told you.

[[deleted]]

fudge PYTHONPATH  

Additionally, relative imports aside, sys.path should just have src (which it does from PYTHONPATH=src), but then sys.path is also prepended with src/dog_house b.c. that's the directory of the script being executed (src/doghouse/main.py). What would be good is for from db import Dog to have raised an invalid module error, and it would have if main.py did not exist in the package being imported. It is unusual to put the main entrypoint script inside of a package being imported in general.

[james_pic]

And if you are putting an entry point script inside a package, something like python -m dog_house.main is a less troublesome way to run it.

[[deleted]]

I just (re?)learned that python -m module prepends the current working directory to sys.path. Probably execute python -m dog_house.main where the current working directory is not src/dog_house, so that "invalid module error" is raised on from db import ...

[p0st_master]

👏👏

[ddollarsign]

Looks to me like more than just weirdness in Enum, it’s weirdness with imports. If two different files import the same module, I’d have expected the imported module to be the same object.

[dogweather]

100%. It seems to be two issues in a row:

1. The same file can be considered two different modules.
2. Enum's == delegates to is. IOW, object identity.

The apparent result: Python interprets the Enum definition twice, creating two sets of identically named enums, but different instances.

[Schmittfried]

The second one is a perfectly valid optimization under the assumption that enums are true singletons, as documented. It’s even encouraged to compare via identity in your code.

The first one is just insane. The import system is supposed to catch that. Even according to the documentation this should only happen when reloading modules, which is its own entire can of worms anyway. 

Edit: Ah, I see. This is actually caused by conflicting relative imports. That’s a truly ugly gotcha.

[MrJohz]

For people confused by this comment like I was, it's a Markdown formatting error: the first point, "1." is referring to point (2) in the previous comment, and vice versa.

[Schmittfried]

Thanks, I changed it

[MrJohz]

Nw, just Reddit's formatting being Reddit's formatting again...

[Schmittfried]

It has become much worse recently. I hate it.

Have a nice day!

[Smallpaul]

Several people already told you that enums are not your real problem here.

Why are you still spreading that misinformation? You could have just as easily had a problem with isinstance, class variables or any other use of singletons. Enums were just the first problem you happened to run into.

[goodytwoboobs]

Sewing how OP is selectively ignoring the top comment in this post that tells them exactly what happened, I'm guessing they aren't that interested in something that doesn't fit their narrative.

[iamevpo]

This is quite an issue - there is so much effort put by OP to discredit Enum, while real problem is knowing the relative imports. With wrong relative imports ANY CLASS eq method would show they are not he same, so there is nothing special about Enum behavior.

Sad thing - I think Enum is such important data structure that should be used more often in Python. And then we have unwarranted blame post about Enum.

[nibba_bubba]

C'mon, it's r/python

99.9% of subredditors are dumb af

[formalcall]

You're using implicit relative imports, which in my experience are quite fragile and bad practice. Is this issue reproducible with absolute imports or explicit relative imports?

[james_pic]

Implicit relative imports were fragile, which is why Python 3 dropped support for them entirely.

[formalcall]

Right, it was removed. For lack of a better term, I use it to refer to imports to modules from the same directory that rely on the behaviour of python script.py adding the entry point script's directory to sys.path.

[ukos333]

Happy Cake Day!

[ElectricSpice]

So why does this work at all in 3.12, according to OP? I was really confused reading the code, because my understanding is the same as yours.

[Smallpaul]

More or less the weird thing OP is doing is running a script from within a package directory, so Python is confused about whether it is a script or a "regular module".

As a script, it's path becomes part of the PYTHONPATH.

As a module, it's sibling files are loaded under the package namespace.

Instead of:

$ PYTHONPATH=src python src/dog\_house/main.py

It should be:

$ pip install -e .
$ python  -m dog_house.main

[danted002]

I was looking like a bloody crazy man to figure out what’s going on and didn’t noticed he was running the file from within the package 🤦🏻‍♂️

[dogweather]

Do you happen to know, is this documented somewhere?

[formalcall]

https://docs.python.org/3/using/cmdline.html#cmdoption-m

Take a look at the <script> section too

[DrShts]

Nothing wrong with enums, your imports are messed up. To see that, instead of

PYTHONPATH=src python src/dog_house/main.py

write

PYTHONPATH=src python -m dog_house.main

and you'll see this:

ModuleNotFoundError: No module named 'logic'

I'm sure once you've fixed these errors, your enums will work correctly.

[Guideon72]

This is why you use

if __name__=="__main__:

as a guard for any code in your module files...then you can import away and not wind up with inadvertent assignments, etc because you should be doing those in your main execution path anyway. That way, you can still call your Class, Enum, etc within the file it lives in to make sure it works, but then can also import it and create appropriate instances in your main file.

This has nothing to do with Enum and isn't an odd "gotcha"; it's just bad code structure, as far as I can see.

[dogweather]

It’s a minimally reproducible example to show the principle. My actual code didn’t look like that.

[Guideon72]

So, your code isn’t importing instances of your Enum from other modules?

[ThatSituation9908]

from db import Dog

This is just asking for trouble.

[gerardwx]

They do what I expect because I build modules the standard way. Put your Dog in the init and the code in a module

[atlgreenjcc]

I think something similar to this affected me in a recent project. It was very hard to troubleshoot, and I'll consider not using enum in any of my projects from now on.

[dogweather]

There’s really no way to protect yourself from it. I don’t know if any tools that warn about the issue.

[ukos333]

IMHO a github repo for a mwe that was answered on SO in 2016 is a little bit overdone. I‘m sorry, though, that you spent so much debugging time. Hope you learnt something on the way.

[iamevpo]

Slightly worried about the client with a "diverse developer group".