feat: Raise uniform error when passing Series of different lengths to with_columns

narwhals/_arrow/utils.py

@@ -13,6 +13,7 @@
 import pyarrow as pa
 import pyarrow.compute as pc
 
+from narwhals.exceptions import ShapeError
 from narwhals.utils import _SeriesNamespace
 from narwhals.utils import import_dtypes_module
 from narwhals.utils import isinstance_or_issubclass
@@ -278,6 +279,9 @@ def extract_dataframe_comparand(
 ) -> ArrowChunkedArray:
     """Extract native Series, broadcasting to `length` if necessary."""
     if not other._broadcast:
+        if (len_other := len(other)) != length:
+            msg = f"Expected object of length {length}, got: {len_other}."
+            raise ShapeError(msg)
         return other.native
 
     import numpy as np  # ignore-banned-import

narwhals/_pandas_like/utils.py

@@ -7,19 +7,21 @@
 from typing import TYPE_CHECKING
 from typing import Any
 from typing import Iterable
+from typing import Sized
 from typing import TypeVar
 from typing import cast
 
 import pandas as pd
 
 from narwhals.exceptions import ColumnNotFoundError
 from narwhals.exceptions import DuplicateError
+from narwhals.exceptions import ShapeError
 from narwhals.utils import Implementation
 from narwhals.utils import Version
 from narwhals.utils import import_dtypes_module
 from narwhals.utils import isinstance_or_issubclass
 
-T = TypeVar("T")
+T = TypeVar("T", bound=Sized)
 
 if TYPE_CHECKING:
     from pandas._typing import Dtype as PandasDtype
@@ -137,6 +139,9 @@ def extract_dataframe_comparand(
     if other._broadcast:
         s = other._native_series
         return s.__class__(s.iloc[0], index=index, dtype=s.dtype, name=s.name)
+    if (len_other := len(other)) != (len_idx := len(index)):
+        msg = f"Expected object of length {len_idx}, got: {len_other}."
+        raise ShapeError(msg)
     if other._native_series.index is not index:
         return set_index(
             other._native_series,

tests/frame/with_columns_test.py

@@ -5,6 +5,7 @@
 import pytest
 
 import narwhals.stable.v1 as nw
+from narwhals.exceptions import ShapeError
 from tests.utils import PYARROW_VERSION
 from tests.utils import Constructor
 from tests.utils import ConstructorEager
@@ -68,3 +69,12 @@ def test_with_columns_dtypes_single_row(
     df = nw.from_native(constructor(data)).with_columns(nw.col("a").cast(nw.Categorical))
     result = df.with_columns(nw.col("a"))
     assert result.collect_schema() == {"a": nw.Categorical}
+
+
+def test_with_columns_series_shape_mismatch(constructor_eager: ConstructorEager) -> None:
+    df1 = nw.from_native(constructor_eager({"first": [1, 2, 3]}), eager_only=True)
+    second = nw.from_native(constructor_eager({"second": [1, 2, 3, 4]}), eager_only=True)[
+        "second"
+    ]
+    with pytest.raises(ShapeError):
+        df1.with_columns(second=second)