py-1.27.0

## 💥 Breaking changes

- Make bottom interval closed in `hist` (#22090)
- Change Partition API to `base_path` and `file_path` (#21888)

## 🚀 Performance improvements

- Add CSE to streaming groupby (#22196)
- Speed-up new streaming predicate filtering (#22179)
- Speedup new-streaming file row count (#22169)
- Fix quadratic behavior when casting Enums (#22008)
- Lower is\_in to bitmap-output semi-join in new streaming engine (#21948)
- Fast path for empty inner join (#21965)
- Add native semi/anti join in new streaming engine (#21937)
- Cache regex compilation globally (#21929)

## ✨ Enhancements

- Add `SPLIT_PART` string function to the SQL interface (#22158)
- Allow scalar expr in `Expr.diff` (#22142)
- Support additional unsigned int aliases in the SQL interface (#22127)
- Add `STRING_TO_ARRAY` function to the SQL interface (#22129)
- Add dt.is\_business\_day (#21776)
- Add an `eager` parameter to `pl.cov` (#22098)
- Add support for `Int128` parsing/recognition to the SQL interface (#22104)
- Add an `eager` parameter to `pl.coalesce` (#22092)
- Add an `eager` parameter to `pl.corr` (#22097)
- Allow sinking to abstract python `io` and `fs` classes (#21987)
- Add `add_alp_optimize_exprs` to `IRBuilder` (#22061)
- Add `cat.slice` (#21971)
- Support growing schema if line lenght increases during csv schema inference (#21979)
- Replace thread unsafe `GilOnceCell` with `Mutex` (#21927)
- Support modified dsl in file cache (#21907)

## 🐞 Bug fixes

- Implode in agg (#22197)
- Reduce GIL hold time for IO plugins in new-streaming (#22186)
- Enhance predicate validation and cast safety in `join_where` (#22112)
- Handle Parquet with compressed empty DataPage v2 (#22172)
- Schema error during lowering (#22175)
- Rewrite unroll of overlapping groups to mitigate out of range index panic (#22072)
- Incorrect rounding for very large/small numbers (#22173)
- Allow set input to `list.set_*` operations (#22163)
- Deadlock in join due to rayon nested task-stealing (#22159)
- Mark `Expr.repeat_by` as elementwise (#22068)
- Fix csv serializer panic by supporting ScalarColumn in as\_single\_chunk (#22146)
- Raise an error if a number doesn't have associated unit in duration strings (#22035)
- Add `i128` as supertype to boolean (#22138)
- Fix panic when constructing DF from pyarrow due to duplicate field names (#22114)
- Add broadcasts and error messages for many elementwise operations (#22130)
- Throw error for `n=0` on `list.gather_every` (#22122)
- Throw error for unsupported rolling operations (#22121)
- Error on unequal length `str.to_integer` arguments (#22100)
- Make bottom interval closed in `hist` (#22090)
- Relative path resolution for plugin libraries (#21911)
- Avoiding panic with striptime for out-of-bounds dates (#21208)
- Join revmaps for categoricals in `merge_sorted` (#21976)
- Fix glob expansion matching extra files (#21991)
- Ensure SQL dot-notation for nested column fields resolves correctly (#22109)
- Parquet filter performance regression from multiscan dispatch (#22116)
- Panic for unequal length `ewm_mean_by` args (#22093)
- Add scalarity checks to `pl.repeat` (#22088)
- Type check `n` parameter of `pl.repeat` (#22071)
- Mark `bitwise_{count,leading,trailing}_{ones,zeros}` as elementwise (#22044)
- Mark `pl.*_ranges` functions correctly as element-wise (#22059)
- Correctly type check `pl.arctan2` (#22060)
- Mark `pl.business_day_count` as elementwise (#22055)
- Check input python type for `str.extract_groups` (#22032)
- Check types for `fill_char` in `str.pad_{start,end}` (#22036)
- Mark `str.to_decimal` properly as non-elementwise (#22040)
- Documented return type for `bin.encode` and `bin.decode` (#22022)
- Revert #22017 and improve block(\_in\_place)\_on doc comment (#22031)
- Remove outdated depth warning (#22030)
- Expression pl.concat was incorrectly marked as elementwise (#22019)
- Use block\_in\_place\_on to start streaming (#22017)
- Panic on empty aggregation in streaming (#22016)
- Error instead of panick for invalid durations in `dt.offset_by()` and `dt.round()` (#21982)
- Raise error instead of silently appending NULL in NDJSON parsing (#21953)
- Ensure AV is static before pushing to row buffer (#21967)
- Deadlock in new-streaming multiplexer (#21963)
- Release GIL in `collect_with_callback` (#21941)
- Panic in new RegexCache (#21935)
- Type hint of `cs.exclude()` is `SelectorType` instead of `Expr` (#21892)
- Add correct deprecation warning for .str.concat (#21666)
- Use absolute paths by defaults for plugins (#21904)

## 📖 Documentation

- Add user guide section on working with Sheets in Colab (#22161)
- Update distributed engine docs (#22128)
- Add Polars Cloud release notes (#22021)
- Remove trailing space in settings POLARS\_CLOUD\_CLIENT\_ID (#21995)
- Fix typo (#21954)
- Fix 'pickleable' typo in docs (#21938)
- Change ctx to compute=ctx for all remote query examples (#21930)

## 🛠️ Other improvements

- Remove old `MultiScanExec` for in-memory (#22184)
- Separate `FunctionOptions` from DSL calls (#22133)
- Undeprecate `backward_fill` and `forward_fill` (#22156)
- Handle conversion of Duration specially in pyir (#22101)
- Deprecate duplicate `backward_fill` and `forward_fill` interface (#22083)
- Solve clippy lints for 1.86 (#22102)
- Remove rust exclusive `MaxBound` and `MinBound` fill strategies (#22063)
- Change Partition API to `base_path` and `file_path` (#21888)
- Fix pydantic model\_fields deprecation (#21958)

Thank you to all our contributors for making this release possible!
@DeflateAwning, @EnricoMi, @Jacob640, @JakubValtar, @MarcoGorelli, @MaxJackson, @alexander-beedie, @amotzop, @anath2, @bschoenmaeckers, @cnpryer, @coastalwhite, @dependabot[bot], @eitsupi, @etiennebacher, @hemanth94, @kdn36, @mcrumiller, @nameexhaustion, @orlp, @r-brink, @rgertenbach, @ritchie46, @sebasv, @silannisik, @stijnherfst, @wence-, @zachlefevre and [dependabot[bot]](https://github.com/apps/dependabot)