Fix EnumSerializer.write to accept numpy scalars from NDArray of records

[SAY-5]

Closes #284.

EnumSerializer.write assumed its value argument was always a Python Enum, but when called from RecordSerializer._write on the numpy write path (where a record is iterated as value['fieldname'] from a np.void scalar), it receives a bare np.integer and crashes with AttributeError: 'numpy.uint64' object has no attribute 'value'. This affected any T[] whose element type was a record containing one or more enum fields.

Fix unwraps .value only when value is an Enum; numpy scalars (which _integer_serializer.write already accepts) are passed through. Adds python/tests/test_enum_in_ndarray.py covering: the original NDArray-of-record-with-enums reproducer, the bare numpy-scalar path directly through EnumSerializer.write, and the existing Python-Enum path (to guard against regression).

[naegelejd]

This is not the right way to test this.

The test model should be updated such that it reproduces the issue. Then regression tests can be added to test_generated_types.py and test_protocol_roundtrip.py. Then, an equivalent test should be added for C++ and MATLAB to ensure no similar bugs exist.

[SAY-5]

Understood, that's a much bigger refactor than I have bandwidth for; happy to close in favour of a more thorough fix.

[SAY-5]

Understood, the proper test should reproduce the bug through the YAML test model and have regression coverage in the generated-types and protocol-roundtrip suites for Python, C++, and MATLAB. That's a substantially different scope from this PR, so I'll close this and open a follow-up once the test model and codegen changes are ready.

[SAY-5]

Closing per maintainer feedback, will resubmit with the proper test model approach.

[SAY-5]

Reopened. Reworking per your feedback: I'll update the test model to reproduce the issue, add regression tests in test_generated_types.py and test_protocol_roundtrip.py, and add equivalent coverage for C++ and MATLAB to confirm no similar bugs exist there. Will push and re-ping.

[SAY-5]

Reworked as discussed. Added recArray: RecordWithEnums[] to the Enums protocol in the test model and regenerated all backends, then added regression coverage to the Python, C++, and MATLAB roundtrip suites plus a dtype assertion in test_generated_types.py. The roundtrip exposed a matching read-path bug, so RecordSerializer.read_numpy now reads enum and nested-record fields via read_numpy so they are numpy-assignable. Removed the standalone test file. Local Python (100 passed), C++ (155 passed) and Go tooling suites are green; CI is waiting on workflow approval.

[Copilot]

Pull request overview

Note

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Fixes a crash in EnumSerializer.write when called from the numpy-record write path where enum fields arrive as bare numpy scalars (rather than Python Enum instances). Also adjusts RecordSerializer.read_numpy so enum and nested-record fields are read via read_numpy, producing numpy-assignable values. Adds a new recArray step to the Enums test protocol and corresponding generated code across C++, Python, and MATLAB targets, plus roundtrip tests.

Changes:

• Unwrap .value in EnumSerializer.write only when input is an Enum; pass numpy scalars through.
• Make RecordSerializer.read_numpy dispatch to read_numpy on Enum/Record field serializers to keep numpy-compatible values.
• Add recArray: RecordWithEnums[] step to the Enums test protocol and regenerate all targets/tests.

Reviewed changes

Copilot reviewed 9 out of 25 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
tooling/internal/python/static_files/_binary.py	Core fix: tolerate numpy scalars in EnumSerializer.write; route Enum/Record subfields via read_numpy in RecordSerializer.read_numpy.
python/tests/test_protocol_roundtrip.py	Adds NDArray-of-records-with-enums roundtrip exercise.
python/tests/test_generated_types.py	Asserts dtype layout for RecordWithEnums.
python/test_model/protocols.py	Regenerated: adds write_rec_array/read_rec_array and updated state machine.
python/test_model/binary.py	Regenerated binary impls for new recArray step.
python/test_model/ndjson.py	Regenerated NDJSON impls for new recArray step.
models/test/unittests.yml	Adds recArray field to the Enums protocol.
matlab/test/RoundTripTest.m	Adds matching MATLAB roundtrip data for recArray.
matlab/generated/+test_model/EnumsWriterBase.m, EnumsReaderBase.m	Regenerated MATLAB base classes with new state.
matlab/generated/+test_model/+binary/EnumsWriter.m, EnumsReader.m	Regenerated MATLAB binary impls.
matlab/generated/+test_model/+testing/*.m	Regenerated MATLAB testing mocks.
cpp/test/roundtrip_test.cc	Adds matching C++ roundtrip data for recArray.
cpp/test/generated/protocols.{h,cc}	Regenerated base protocol with new step and state.
cpp/test/generated/{binary,ndjson,hdf5}/protocols.{h,cc}	Regenerated backend impls.
cpp/test/generated/mocks.cc	Regenerated mock with new expectation method.
cpp/test/generated/model.json	Regenerated schema.

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