build requirement gets removed for no apparent reason

[Dobatymo]

Hi, great project!

I have the following in my pyproject file

[build-system]
requires = [
  "cython==3.0.11",
  "numpy==1.22.2; python_version<'3.9'",
  "numpy>=2; python_version>='3.9'",
  "setuptools",
]

when running pyproject-fmt==2.2.4 using pre-commit the "numpy==1.22.2; python_version<'3.9'", line gets removed. Is that a bug or some configuration option I missed?

[gaborbernat]

It is a bug.