implode + explode + over PanicException #24616
Description
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
import polars as pl
df = pl.DataFrame({"x": [[1, 2]]})
df.select(pl.col.x.implode().explode().over(1))
# pyo3_runtime.PanicException: called `Result::unwrap()` on an `Err` value: ComputeError(ErrString("dtypes don't match, got list[i64], expected: list[list[i64]]"))Log output
thread 'polars-2' (149360) panicked at polars/crates/polars-core/src/chunked_array/from_iterator_par.rs:261:85:
called `Result::unwrap()` on an `Err` value: ComputeError(ErrString("dtypes don't match, got i64, expected: list[i64]"))Issue description
This did not panic on 1.31.0
shape: (2, 1)
┌─────┐
│ x │
│ --- │
│ i64 │
╞═════╡
│ 1 │
│ 2 │
└─────┘
Expected behavior
No panic.
Installed versions
--------Version info---------
Polars: 1.34.0-beta.1
Index type: UInt32
Platform: macOS-13.6.1-arm64-arm-64bit-Mach-O
Python: 3.13.3 (main, Apr 8 2025, 13:54:08) [Clang 15.0.0 (clang-1500.1.0.2.5)]
LTS CPU: False
----Optional dependencies----
Azure CLI <not installed>
adbc_driver_manager <not installed>
altair <not installed>
azure.identity <not installed>
boto3 <not installed>
cloudpickle <not installed>
connectorx <not installed>
deltalake 1.1.4
fastexcel 0.14.0
fsspec 2025.3.2
gevent <not installed>
google.auth <not installed>
great_tables 0.17.0
matplotlib 3.10.0
numpy 2.3.2
openpyxl 3.1.5
pandas 2.2.3
polars_cloud <not installed>
pyarrow 21.0.0
pydantic 2.11.4
pyiceberg 0.9.1
sqlalchemy 2.0.40
torch <not installed>
xlsx2csv <not installed>
xlsxwriter 3.2.0```
</details>