BLD: enable building NumPy with Meson

This enables building with NumPy on Linux and macOS. Windows support
should be complete to, but is untested as of now and may need a few
tweaks. This contains:
- A set of `meson.build` files and related code generation script
  tweaks, header templates, etc.
- One CI job on Linux
- Basic docs on using Meson to build NumPy (not yet integrated in the
  html docs, it's too early for that - this is for early adopters right
  now).

The build should be complete, with the major exception of SIMD support.
The full test suite passes. See gh-22546 for the tracking issue with
detailed notes on the plan for switching NumPy to Meson as its build
system.

Co-authored-by: Stefan van der Walt <stefanv@berkeley.edu>

1 files changed, 164 insertions, 0 deletions

diff --git a/numpy/random/meson.build b/numpy/random/meson.build
new file mode 100644
index 000000000..cc61c66dd
--- /dev/null
+++ b/numpy/random/meson.build
@@ -0,0 +1,164 @@
+# Build npyrandom library
+# -----------------------
+npyrandom_sources = [
+  'src/distributions/logfactorial.c',
+  'src/distributions/distributions.c',
+  'src/distributions/random_mvhg_count.c',
+  'src/distributions/random_mvhg_marginals.c',
+  'src/distributions/random_hypergeometric.c',
+]
+
+npyrandom_lib = static_library('npyrandom',
+  npyrandom_sources,
+  c_args: staticlib_cflags,
+  # include_directories: '../core/include',
+  dependencies: [py_dep, np_core_dep],
+  install: true,
+  install_dir: np_dir / 'random/lib',
+)
+
+# Build Cython extensions for numpy.random
+# ----------------------------------------
+# pyx -> c transpile output depends on copied __init__.py and pxd files
+_cython_tree_random = [
+  fs.copyfile('__init__.py'),
+  fs.copyfile('__init__.pxd'),
+  fs.copyfile('_common.pxd'),
+  fs.copyfile('bit_generator.pxd'),
+  fs.copyfile('c_distributions.pxd'),
+]
+# Need to use `custom_target` because we need to install this .pxd file
+_cython_tree_random += custom_target('_bounded_integer_pxd',
+  output: '_bounded_integers.pxd',
+  input: '_bounded_integers.pxd.in',
+  command: [tempita_cli, '@INPUT@', '-o', '@OUTPUT@'],
+  install: true,
+  install_dir: np_dir / 'random'
+)
+
+_bounded_integers_pyx = custom_target('_bounded_integer_pyx',
+  output: '_bounded_integers.pyx',
+  input: '_bounded_integers.pyx.in',
+  command: [tempita_cli, '@INPUT@', '-o', '@OUTPUT@'],
+)
+
+c_args_random = [
+  cflags_large_file_support,
+  '-DNPY_NO_DEPRECATED_API=0',  # Cython still uses old NumPy C API
+]
+if host_machine.system() == 'cygwin'
+  c_args_random += ['-Wl,--export-all-symbols']
+endif
+
+# name, sources, extra link libs, extra c_args
+random_pyx_sources = [
+  ['_bounded_integers', _bounded_integers_pyx, [], npymath_lib],
+  ['_common', '_common.pyx', [], []],
+  ['_mt19937', ['_mt19937.pyx', 'src/mt19937/mt19937.c', 'src/mt19937/mt19937-jump.c'], [], []],
+  ['_philox', ['_philox.pyx', 'src/philox/philox.c'], [], []],
+  ['_pcg64', ['_pcg64.pyx', 'src/pcg64/pcg64.c'], ['-U__GNUC_GNU_INLINE__'], []],
+  ['_sfc64', ['_sfc64.pyx', 'src/sfc64/sfc64.c'], [], []],
+  ['bit_generator', 'bit_generator.pyx', [], []],
+  # The `fs.copyfile` usage here is needed because these two .pyx files import
+  # from _bounded_integers,and its pxd file is only present in the build directory
+  ['_generator', fs.copyfile('_generator.pyx'), [], npymath_lib],
+  ['mtrand', [
+      fs.copyfile('mtrand.pyx'),
+      'src/distributions/distributions.c',
+      'src/legacy/legacy-distributions.c'
+    ], ['-DNPY_RANDOM_LEGACY=1'], npymath_lib,
+  ],
+]
+foreach gen: random_pyx_sources
+  py.extension_module(gen[0],
+    [gen[1], _cython_tree, _cython_tree_random],
+    c_args: [c_args_random, gen[2]],
+    include_directories: 'src',
+    dependencies: np_core_dep,
+    link_with: [npyrandom_lib, gen[3]],
+    install: true,
+    subdir: 'numpy/random',
+  )
+endforeach
+
+# Install Python sources, stub files, tests, examples and license
+# ---------------------------------------------------------------
+py.install_sources(
+  [
+    '__init__.pxd',
+    '__init__.py',
+    '__init__.pyi',
+    '_common.pxd',
+    '_generator.pyi',
+    '_mt19937.pyi',
+    '_pcg64.pyi',
+    '_pickle.py',
+    '_philox.pyi',
+    '_sfc64.pyi',
+    'bit_generator.pxd',
+    'bit_generator.pyi',
+    'c_distributions.pxd',
+    'LICENSE.md',
+    'mtrand.pyi',
+  ],
+  subdir: 'numpy/random'
+)
+
+py.install_sources(
+  [
+    'tests/__init__.py',
+    'tests/test_direct.py',
+    'tests/test_extending.py',
+    'tests/test_generator_mt19937.py',
+    'tests/test_generator_mt19937_regressions.py',
+    'tests/test_random.py',
+    'tests/test_randomstate.py',
+    'tests/test_randomstate_regression.py',
+    'tests/test_regression.py',
+    'tests/test_seed_sequence.py',
+    'tests/test_smoke.py',
+  ],
+  subdir: 'numpy/random/tests'
+)
+
+py.install_sources(
+  [
+    'tests/data/__init__.py',
+    'tests/data/mt19937-testset-1.csv',
+    'tests/data/mt19937-testset-2.csv',
+    'tests/data/pcg64-testset-1.csv',
+    'tests/data/pcg64-testset-2.csv',
+    'tests/data/pcg64dxsm-testset-1.csv',
+    'tests/data/pcg64dxsm-testset-2.csv',
+    'tests/data/philox-testset-1.csv',
+    'tests/data/philox-testset-2.csv',
+    'tests/data/sfc64-testset-1.csv',
+    'tests/data/sfc64-testset-2.csv',
+  ],
+  subdir: 'numpy/random/tests/data'
+)
+
+py.install_sources(
+  [
+  '_examples/cffi/extending.py',
+  '_examples/cffi/parse.py',
+  ],
+  subdir: 'numpy/random/_examples/cffi'
+)
+
+py.install_sources(
+  [
+  '_examples/cython/extending.pyx',
+  '_examples/cython/extending_distributions.pyx',
+  '_examples/cython/setup.py',
+  ],
+  subdir: 'numpy/random/_examples/cython'
+)
+
+py.install_sources(
+  [
+  '_examples/numba/extending.py',
+  '_examples/numba/extending_distributions.py',
+  ],
+  subdir: 'numpy/random/_examples/numba'
+)