jingyi-zhao-01 commented on issue #49384:
URL: https://github.com/apache/arrow/issues/49384#issuecomment-5010542207
I can still reproduce this on current Arrow main / local PyArrow dev build:
- pyarrow `26.0.0.dev3+gb03b4c539`
- numpy `2.5.1`
Minimal repro:
```python
import numpy as np
import pyarrow as pa
for arr in [pa.chunked_array([[2, 3]]), pa.chunked_array([[2], [3]])]:
out = np.array(arr, copy=True)
print(arr.num_chunks, out.flags.owndata, out.flags.writeable)
try:
out[0] = 99
print("mutation ok", out.tolist())
except Exception as exc:
print(type(exc).__name__, exc)
```
Observed output:
```text
1 False False
ValueError assignment destination is read-only
2 False True
mutation ok [99, 3]
```
So this still matches the earlier analysis: the single-chunk path can return
a zero-copy read-only NumPy view even when `copy=True`, while the multi-chunk
path materializes a writable array.
Minimal ask: if nobody is currently working on it, I can take a shot at a
small regression test plus a narrow fix in `ChunkedArray.__array__` to make the
single-chunk path respect `copy=True`.
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