Release Narwhals v1.21.0 · narwhals-dev/narwhals

Changes

fix: always pass Column to pandas.spark.functions (#1712)
tests: add 'core' to nox dependencies (#1713)
feat: add weekday to Pandas, Dask and Arrow dt namespaces (#1680)
Link to Avoiding the UserWarning error while using Pandas group_by page when warning is thrown (#1683)

feat: Implement partial "lazy" support for DuckDB (even with this PR, DuckDB support is work-in-progress!) (#1725)
feat: validate library minimum version in compliant objects (#1727)
feat: enable to cast to Struct dtype (#1717)
feat: Expressify clip arguments (#1709)
feat: add is_nan expression & series method (#1625)
feat: show native object (if possible) in repr (#1702)
feat: add sum and sum_horizontal for SparkLike (#1693)
feat: add some SparkLikeLazyFrame methods (#1633)

fix: fix broken link from warning (#1732)
fix: nw.lit(date, dtype=nw.Date), loosen Dask minimum back to 2024.8 (#1730)
chore: simplify definitions of rhs expressions, bump dask minimum to 2024.10 (#1720)
fix: dask group by with kwargs (#1676)
fix: DaskLazyFrame and ArrowDataFrame .with_row_index column order (#1706)
fix: scalar reductions on empty inputs (#1715)
fix: remove maintain_order from LazyFrame.unique (#1687)
fix: modin dtype interoperability (#1692)
fix: Dask was raising for scalar vs Series binary operations (#1684)
fix: casting to List for cudf (#1686)

docs: Expr method' docstrings (#1733)
docs: let nw.LazyFrame docstrings examples run on Polars and Dask only (#1700)
docs: update null handling page with is_nan reference (#1716)
docs: add spark-like in backend completeness (#1710)
docs: Series method' docstrings (#1699)
docs: DataFrame method' docstrings (#1688)

test: catch some cudf failures (#1735)
chore: refactor root_names and output_names tracking (#1731)
tests: remove unnecessary pytest filterwarnings (#1691)
chore: remove some lazy tests (#1719)
fix: Catch cuDF warning for concat with empty elements, and ComputeError for non-float is_nan (#1718)
chore: use None instead of float('nan') to check for null values in tests (#1697)
test: allow to run tests for Polars[gpu] (#1698)
test: Make constructors configurable when running tests (#1694)