BUG: `pythran` min version not enforced

[lucascolley]

Describe your issue.

Despite pythran>=0.14.0 in pyproject.toml, python dev.py build lets me build with pythran=0.13.1. This is not true for Cython, where the >=3.0.4 bound is enforced.

Reproducing Code Example

python dev.py build # with pythran=0.13.1

Error message

# a wall of warnings which were fixed, hence we bumped the min version

SciPy/NumPy/Python version and system information

1.13.0.dev0+1030.3b33204 1.25.2 sys.version_info(major=3, minor=10, micro=12, releaselevel='final', serial=0)
Build Dependencies:
  blas:
    detection method: pkgconfig
    found: true
    include directory: /Users/lucascolley/mambaforge/envs/scipy-dev/include
    lib directory: /Users/lucascolley/mambaforge/envs/scipy-dev/lib
    name: openblas
    openblas configuration: USE_64BITINT=0 DYNAMIC_ARCH=0 DYNAMIC_OLDER= NO_CBLAS=
      NO_LAPACK=0 NO_LAPACKE= NO_AFFINITY=1 USE_OPENMP=1 VORTEX MAX_THREADS=128
    pc file directory: /Users/lucascolley/mambaforge/envs/scipy-dev/lib/pkgconfig
    version: 0.3.23
  lapack:
    detection method: pkgconfig
    found: true
    include directory: /Users/lucascolley/mambaforge/envs/scipy-dev/include
    lib directory: /Users/lucascolley/mambaforge/envs/scipy-dev/lib
    name: openblas
    openblas configuration: USE_64BITINT=0 DYNAMIC_ARCH=0 DYNAMIC_OLDER= NO_CBLAS=
      NO_LAPACK=0 NO_LAPACKE= NO_AFFINITY=1 USE_OPENMP=1 VORTEX MAX_THREADS=128
    pc file directory: /Users/lucascolley/mambaforge/envs/scipy-dev/lib/pkgconfig
    version: 0.3.23
  pybind11:
    detection method: pkgconfig
    include directory: /Users/lucascolley/mambaforge/envs/scipy-dev/include
    name: pybind11
    version: 2.11.1
Compilers:
  c:
    args: -ftree-vectorize, -fPIC, -fPIE, -fstack-protector-strong, -O2, -pipe, -isystem,
      /Users/lucascolley/mambaforge/envs/scipy-dev/include, -D_FORTIFY_SOURCE=2, -isystem,
      /Users/lucascolley/mambaforge/envs/scipy-dev/include
    commands: arm64-apple-darwin20.0.0-clang
    linker: ld64
    linker args: -Wl,-pie, -Wl,-headerpad_max_install_names, -Wl,-dead_strip_dylibs,
      -Wl,-rpath,/Users/lucascolley/mambaforge/envs/scipy-dev/lib, -L/Users/lucascolley/mambaforge/envs/scipy-dev/lib,
      -ftree-vectorize, -fPIC, -fPIE, -fstack-protector-strong, -O2, -pipe, -isystem,
      /Users/lucascolley/mambaforge/envs/scipy-dev/include, -D_FORTIFY_SOURCE=2, -isystem,
      /Users/lucascolley/mambaforge/envs/scipy-dev/include
    name: clang
    version: 15.0.7
  c++:
    args: -ftree-vectorize, -fPIC, -fPIE, -fstack-protector-strong, -O2, -pipe, -stdlib=libc++,
      -fvisibility-inlines-hidden, -fmessage-length=0, -isystem, /Users/lucascolley/mambaforge/envs/scipy-dev/include,
      -D_FORTIFY_SOURCE=2, -isystem, /Users/lucascolley/mambaforge/envs/scipy-dev/include
    commands: arm64-apple-darwin20.0.0-clang++
    linker: ld64
    linker args: -Wl,-pie, -Wl,-headerpad_max_install_names, -Wl,-dead_strip_dylibs,
      -Wl,-rpath,/Users/lucascolley/mambaforge/envs/scipy-dev/lib, -L/Users/lucascolley/mambaforge/envs/scipy-dev/lib,
      -ftree-vectorize, -fPIC, -fPIE, -fstack-protector-strong, -O2, -pipe, -stdlib=libc++,
      -fvisibility-inlines-hidden, -fmessage-length=0, -isystem, /Users/lucascolley/mambaforge/envs/scipy-dev/include,
      -D_FORTIFY_SOURCE=2, -isystem, /Users/lucascolley/mambaforge/envs/scipy-dev/include
    name: clang
    version: 15.0.7
  cython:
    commands: cython
    linker: cython
    name: cython
    version: 3.0.4
  fortran:
    args: -march=armv8.3-a, -ftree-vectorize, -fPIC, -fno-stack-protector, -O2, -pipe,
      -isystem, /Users/lucascolley/mambaforge/envs/scipy-dev/include
    commands: /Users/lucascolley/mambaforge/envs/scipy-dev/bin/arm64-apple-darwin20.0.0-gfortran
    linker: ld64
    linker args: -Wl,-pie, -Wl,-headerpad_max_install_names, -Wl,-dead_strip_dylibs,
      -Wl,-rpath,/Users/lucascolley/mambaforge/envs/scipy-dev/lib, -L/Users/lucascolley/mambaforge/envs/scipy-dev/lib,
      -march=armv8.3-a, -ftree-vectorize, -fPIC, -fno-stack-protector, -O2, -pipe,
      -isystem, /Users/lucascolley/mambaforge/envs/scipy-dev/include
    name: gcc
    version: 12.3.0
  pythran:
    include directory: ../../../mambaforge/envs/scipy-dev/lib/python3.10/site-packages/pythran
    version: 0.13.1
Machine Information:
  build:
    cpu: aarch64
    endian: little
    family: aarch64
    system: darwin
  cross-compiled: false
  host:
    cpu: aarch64
    endian: little
    family: aarch64
    system: darwin
Python Information:
  path: /Users/lucascolley/mambaforge/envs/scipy-dev/bin/python3.10
  version: '3.10'

[lucascolley]

Do we just need to add something like

if not pythran.version().version_compare('>=0.14.0')
  error('SciPy requires pythran >= 0.14.0')
endif

to

scipy/meson.build

Lines 137 to 143 in 3b33204

	if use_pythran
	pythran = find_program('pythran', native: true)
	# xsimd is unvendored from pythran by conda-forge, and due to a compiler
	# activation bug the default <prefix>/include/ may not be visible (see
	# gh-15698). Hence look for xsimd explicitly.
	xsimd_dep = dependency('xsimd', required: false)
	endif

?

[tylerjereddy]

Your proposed solution sounds correct to me, as you know the pyproject.toml guard mostly applies to the isolated pip build.