mpy-cross: Fix output to stdout on Windows. #17879
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Set stdout to binary mode on Windows to avoid corruption of MPY output. By default, Windows uses text mode for stdout which will convert any newline byte (\n) to a carriage return + newline (\r\n) pair. This can corrupt the MPY output if the MPY contains any 0x0A byte. Signed-off-by: David Lechner <david@pybricks.com>
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Summary
Set stdout to binary mode on Windows to avoid corruption of MPY output.
By default, Windows uses text mode for stdout which will convert any newline byte (\n) to a carriage return + newline (\r\n) pair. This can corrupt the MPY output if the MPY contains any 0x0A byte.
Testing
I didn't see a way to test this using our existing test framework. But I have made a test in the python-mpy-cross project I maintain.
Failing test before the fix: https://github.com/pybricks/python-mpy-cross/actions/runs/16865780805/job/47772458449#step:4:538
Passing test after the fix: https://github.com/pybricks/python-mpy-cross/actions/runs/16866365087/job/47773824320#step:4:863
Test source: https://github.com/pybricks/python-mpy-cross/blob/f376b412573a0c8c825abc300c5e36a716a85f98/tests/test_mpy_cross.py#L40-L50