Build: -C foo=disable no longer disables component build

[adamjstewart]

What did you do?

I used --config-settings=xcb=disable (equivalent to -C xcb=disable) to disable the build of the xcb feature. Same thing for freetype.

What did you expect to happen?

According to https://pillow.readthedocs.io/en/stable/installation/building-from-source.html#build-options, I expected this build to be skipped.

What actually happened?

The features were built. See the full build log for details:
spack-build-out.txt.gz

What are your OS, Python and Pillow versions?

• OS: macOS 15.0.1
• Python: 3.11.9
• Pillow: 11.0.0

Note that this issue does not occur in pillow 10.4.0, it is new in 11.0.0.

--------------------------------------------------------------------
Pillow 11.0.0
Python 3.11.9 (main, Oct  5 2024, 11:35:21) [Clang 16.0.0 (clang-1600.0.26.3)]
--------------------------------------------------------------------
Python executable is /Users/Adam/spack/opt/spack/darwin-sequoia-m2/apple-clang-16.0.0/python-venv-1.0-mcw7wh5o6eq6ztq244pxsof6xdozpwk3/bin/python3
Environment Python files loaded from /Users/Adam/spack/opt/spack/darwin-sequoia-m2/apple-clang-16.0.0/python-venv-1.0-mcw7wh5o6eq6ztq244pxsof6xdozpwk3
System Python files loaded from /Users/Adam/spack/opt/spack/darwin-sequoia-m2/apple-clang-16.0.0/python-3.11.9-miamin5zo2vhkrb22ej7xpjqlcjsuugs
--------------------------------------------------------------------
Python Pillow modules loaded from /Users/Adam/spack/opt/spack/darwin-sequoia-m2/apple-clang-16.0.0/py-pillow-11.0.0-vzj6uqkzf4blfwabed6ccgcmliu2t7wl/lib/python3.11/site-packages/PIL
Binary Pillow modules loaded from /Users/Adam/spack/opt/spack/darwin-sequoia-m2/apple-clang-16.0.0/py-pillow-11.0.0-vzj6uqkzf4blfwabed6ccgcmliu2t7wl/lib/python3.11/site-packages/PIL
--------------------------------------------------------------------
--- PIL CORE support ok, compiled for 11.0.0
*** TKINTER support not installed
--- FREETYPE2 support ok, loaded 2.12.1
*** LITTLECMS2 support not installed
*** WEBP support not installed
--- JPEG support ok, compiled for libjpeg-turbo 3.0.3
--- OPENJPEG (JPEG2000) support ok, loaded 2.5.2
--- ZLIB (PNG/ZIP) support ok, loaded 1.3.1.zlib-ng
--- LIBTIFF support ok, loaded 4.6.0
*** RAQM (Bidirectional Text) support not installed
*** LIBIMAGEQUANT (Quantization method) support not installed
--- XCB (X protocol) support ok
--------------------------------------------------------------------

[radarhere]

I've created #8469 to resolve this.