Apply normalization consistently in VLenBytes #570
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None and 0 are treated like a 0 length string when computing lengths, and the same normalization should be applied to the value passed to PyBytes_AS_STRING. If this is not done, an assertion is hit in the python runtime (when compiled in debug mode).
numcodecs/vlen.pyx
Outdated
| @@ -250,7 +250,10 @@ class VLenBytes(Codec): | |||
| l = lengths[i] | |||
| store_le32(<uint8_t*>data, l) | |||
| data += 4 | |||
| encv = PyBytes_AS_STRING(values[i]) | |||
| b = values[i] | |||
| if b is None or b == 0: # treat these as missing value, normalize | |||
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Like on line 231? It seems like l = 0 in this case, there is nothing to copy, and these operations are wasted. I might be wrong...
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If you don't pass a bytes object, you will hit this assert when calling PyBytes_AS_STRING: https://github.com/python/cpython/blob/40fff90ae3d46843bb9d27c6a53ef61c861a3bb4/Include/cpython/bytesobject.h#L21
it would be equivalent to skip the PyBytes_AS_STRING and memcpy entirely if l = 0. Shall I update the PR to do that instead?
Codecov ReportAll modified and coverable lines are covered by tests ✅
Additional details and impacted files@@ Coverage Diff @@
## main #570 +/- ##
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Coverage 99.91% 99.91%
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Files 59 59
Lines 2334 2334
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Hits 2332 2332
Misses 2 2 |
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None and 0 are treated like a 0 length string when computing lengths, and the same normalization should be applied to the value passed to PyBytes_AS_STRING. If this is not done, an assertion is hit in the python runtime (when compiled in debug mode).
TODO: