feat: Add support for nw.int_range for eager backends

[FBruzzesi]

What type of PR is this? (check all applicable)

• 💾 Refactor
• ✨ Feature
• 🐛 Bug Fix
• 🔧 Optimization
• 📝 Documentation
• ✅ Test
• 🐳 Other

Checklist

• Code follows style guide (ruff)
• Tests added
• Documented the changes

If you have comments or can explain your changes, please do so below

Related issue: #2722

I am slightly concerned that this could turn out to be a month long PR. I will open it as draft for now. There are a couple of pain points I already know:

• I was very careful with type hints, yet it somehow doesn't pass type checker Fixed
• A custom check (importing from dtypes) will fail. That's the default used in the dtype argument. In principle we could just ignore the argument completely and always opt for Int64.
• Polars can do eager: bool. In our case it's a bit more complex than that. Instead of adding yet another argument to the function, I allowed for eager to be False (default), None or the backend/implementation that should back the series.

[dangotbanned]

Hey @FBruzzesi, as I've mentioned 8347839 times, I'm very keen to see this in narwhals! 😄

Would you be okay if we let this one marinate for a bit and maybe target the release after the next? 🙏

[FBruzzesi]

Hey @FBruzzesi,as I've mentioned 8347839 times, I'm very keen to see this in narwhals! 😄

🎉

Would you be okay if we let this one marinate for a bit and maybe target the release after the next? 🙏

Yeah I was not expecting this to be finalized by tomorrow. It has some sharp edges that need some love and work

[FBruzzesi]

@MarcoGorelli any "trick" to avoid the custom check in precommit?

• For compliant namespaces the import of IntegerType is in the if TYPE_CHECKING block
• For function.py, Int64 is used as default value (and then overwritten by the v*.dtypes.Int64 dtype). I guess one way of doing it is to let it be None and set it inside the function given the version. Yet It's a bit less explicit to a user.

I thought about emulating that utils/import_check.py does, but I would need to figure out what's happening there from scratch 😂

[dangotbanned]

any "trick" to avoid the custom check in precommit?

You could add this to nw.typing, and then use that everywhere instead?

IntegerDType: TypeAlias = "dtypes.IntegerType | type[dtypes.IntegerType]"

[dangotbanned]

this is probably fine, i'd just like to take a look before merging please, thanks 🙏

@MarcoGorelli pinging again as (#2895 (comment)) was a month ago 🫣