Does needs_recompile work in build isolation?

[ketozhang]

Docs does not mention this, but the source code does.

pybind11/pybind11/setup_helpers.py

Lines 391 to 394 in 296615a

	needs_recompile:
	A function of (obj, src) that returns True when recompile is needed. No
	effect in isolated mode; use ccache instead, see
	https://github.com/matplotlib/matplotlib/issues/1507/

In this minimal setup.py file (pyproject.toml not shown),

ParallelCompile(default=0, needs_recompile=naive_recompile).install()

ext_modules = Pybind11Extension(
    "myextpkg",
    sources=["src/myextpkg.cpp"]
)

setup(ext_modules=ext_modules)

After building once so the object files exists in src/myextpkg.cpython-***.so, I recompile with...

$ time pip install -e .
23.71s user 3.72s system 99% cpu 27.696 total

$ time pip install --no-build-isolation -e .
3.22s user 1.06s system 116% cpu 3.679 total

[LukeLIN-web]

So you mean it can make it work quicker?
pybind11 doc emits many details. I often feel confused when I read it.