--require-archs shall check all mach-O files in the wheel

[mayeut]

Is your feature request related to a problem? Please describe.
delocate-wheel --require-archs arm64,x86_64 is not enforced for executables, at least, already present in the wheel being repaired. This is not intuitive and I wonder if this is a bug or a feature ?

Describe the solution you'd like
I'd like --require-archs to be enforced on all mach-O files in the wheel.

Describe alternatives you've considered
worked around by extracting the wheel & checking files "manually" with lipo -verify_arch

Additional context
scikit-build/ninja-python-distributions#88
scikit-build/ninja-python-distributions#90

Invalid wheel being generated: https://files.pythonhosted.org/packages/95/7c/ce1487f88a00e43825a73d5395adc8e200af06c08017b204efe6c3ff8992/ninja-1.10.2.2-py2.py3-none-macosx_10_9_universal2.macosx_10_9_x86_64.macosx_11_0_arm64.macosx_11_0_universal2.whl

[HexDecimal]

I'd consider it a bug.

The problem is how delocate.delocating.check_archs takes the tree_libs variable, but that variable only tracks dependencies which will be copied and does not consider that any other files could have architectures. Any files which have architectures but don't rely on non-system libraries outside of the wheel will be missed by check_archs which is why --require-archs fails.

check_archs should be modified to take a directory and iterate over every file in it.