is_in fails with custom Collection

[harrymconner]

Checks

• I have checked that this issue has not already been reported.
• I have confirmed this bug exists on the latest version of Polars.

Reproducible example

This MRE shows is_in failing for a custom Collection but succeeding for a custom Sequence.

from collections.abc import Collection, Iterator, Sequence
from typing import overload

import polars as pl

df = pl.DataFrame({"A": [1, 2, 3]})


class CustomCollection(Collection[int]):
    def __init__(self, vals: Collection[int]) -> None:
        super().__init__()
        self.vals = vals

    def __contains__(self, x: object) -> bool:
        return x in self.vals

    def __iter__(self) -> Iterator[int]:
        yield from self.vals

    def __len__(self) -> int:
        return len(self.vals)


coll = CustomCollection([2, 3, 4])
print(f"CustomCollection is Collection: {isinstance(coll, Collection)}")  # True


try:
    df.filter(pl.col("A").is_in(coll))
except TypeError as e:
    # TypeError: Series constructor called with unsupported type 'CustomCollection' for the `values` parameter
    print(e, "\n")


class CustomSequence(Sequence[int]):
    def __init__(self, vals: Sequence[int]) -> None:
        super().__init__()
        self.vals = vals

    def __len__(self) -> int:
        return len(self.vals)

    @overload
    def __getitem__(self, index: slice) -> Sequence[int]: ...

    @overload
    def __getitem__(self, index: int) -> int: ...

    def __getitem__(self, index: int | slice) -> int | Sequence[int]:
        return self.vals[index]


seq = CustomSequence([2, 3, 4])
print(f"CustomSequence is Sequence: {isinstance(seq, Sequence)}")  # True

print(df.filter(pl.col("A").is_in(seq)))

Log output

Issue description

The other parameter in the is_in method is annotated to accept Expr | Collection[Any] | Series. However, passing a custom Collection raises a TypeError when is_in tries to convert the custom Collection to a pl.Series. The isinstance checks in pl.Series look for Sequences but not Collections, which is resulting in the TypeError. Perhaps the type annotation for the other parameter of is_in should be updated to reflect that pl.Series expects a Sequence instead of a Collection?

Expected behavior

Passing a custom Collection to is_in behaves the same as passing a native list, tuple, etc.

Installed versions

--------Version info---------
Polars:              1.20.0
Index type:          UInt32
Platform:            Windows-11-10.0.26100-SP0
Python:              3.12.8 (main, Dec 19 2024, 14:41:01) [MSC v.1942 64 bit (AMD64)]
LTS CPU:             False

----Optional dependencies----
Azure CLI            'az' is not recognized as an internal or external command,
operable program or batch file.
<not installed>
adbc_driver_manager  <not installed>
altair               <not installed>
azure.identity       <not installed>
boto3                <not installed>
cloudpickle          <not installed>
connectorx           <not installed>
deltalake            <not installed>
fastexcel            0.12.1
fsspec               2024.12.0
gevent               <not installed>
google.auth          <not installed>
great_tables         <not installed>
matplotlib           <not installed>
nest_asyncio         <not installed>
numpy                2.2.1
openpyxl             <not installed>
pandas               <not installed>
pyarrow              19.0.0
pydantic             2.10.5
pyiceberg            <not installed>
sqlalchemy           2.0.37
torch                <not installed>
xlsx2csv             <not installed>
xlsxwriter           3.2.0

[MarcoGorelli]

Thanks @harrymconner for the report

I think the current check

            if isinstance(other, (set, frozenset)):
                other = list(other)

might be too tight