Compile everything with meson

.github/workflows/ci-meson.yml

@@ -0,0 +1,76 @@
+name: Build & Test using Meson
+
+on:
+  push:
+    branches:
+      - master
+      - develop
+  pull_request:
+  workflow_dispatch:
+    # Allow to run manually
+
+concurrency:
+  # Cancel previous runs of this workflow for the same branch
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  test:
+    name: Conda (${{ matrix.os }}, Python ${{ matrix.python }})
+    runs-on: ${{ matrix.os }}-latest
+
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu, macos]
+        python: ['3.9', '3.10', '3.11']
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Merge CI fixes from sagemath/sage
+        run: |
+          .ci/merge-fixes.sh
+        env:
+          GH_TOKEN: ${{ github.token }}
+
+      - name: Cache conda packages
+        uses: actions/cache@v3
+        with:
+          path: ~/conda_pkgs_dir
+          key:
+            ${{ runner.os }}-conda-${{ hashFiles('src/environment-3.11-linux.yml') }}
+
+      - name: Compiler cache
+        uses: hendrikmuhs/ccache-action@v1.2
+        with:
+          key: ${{ runner.os }}-meson-${{ matrix.python }}
+
+      - name: Setup Conda environment
+        uses: conda-incubator/setup-miniconda@v2
+        with:
+          python-version: ${{ matrix.python }}
+          miniforge-version: latest
+          use-mamba: true
+          channels: conda-forge
+          channel-priority: true
+          activate-environment: sage
+          environment-file: src/environment-${{ matrix.python }}-${{ startsWith(matrix.os, 'macos') && 'macos' || 'linux' }}.yml
+
+      - name: Print Conda environment
+        shell: bash -l {0}
+        run: |
+          conda info
+          conda list
+
+      - name: Build
+        shell: bash -l {0}
+        run: |
+          export PATH="/usr/lib/ccache:/usr/local/opt/ccache/libexec:$PATH"
+          export CC="ccache $CC"
+          export CXX="ccache $CXX"
+          pip install --no-build-isolation --config-settings=builddir=builddir . -v
+
+      - name: Test
+        shell: bash -l {0}
+        run: ./sage -t --all -p4

.gitignore

@@ -150,6 +150,7 @@ __pycache__/
 # Generated Cython files
 *.so
 **/*.so
+**/*.so.old
 /src/cython_debug
 # Most C and C++ files are generated by Cython and should not
 # be included in the sdist.
@@ -298,3 +299,7 @@ src/.coverage/
 # git worktree
 worktree*
 **/worktree*
+
+# meson build directory
+builddir
+builddir-*

bootstrap-conda

@@ -98,6 +98,9 @@ echo >&2 $0:$LINENO: generate conda environment files
     ) > environment-template.yml
     (
         sed 's/name: sage-build/name: sage/' environment-template.yml
+        echo "  - meson"
+        echo "  - meson-python"
+        echo "  - pytest"
         echo "  # Additional packages providing all dependencies for the Sage library"
         for pkg in $SAGELIB_SYSTEM_PACKAGES; do
             echo "  - $pkg"

meson.build

@@ -0,0 +1,32 @@
+project(
+  'SageMath',
+  ['c', 'cpp', 'cython'],
+  version: files('src/VERSION.txt'),
+  license: 'GPL v3'
+)
+
+# Python module
+# https://mesonbuild.com/Python-module.html
+py_module = import('python')
+py = py_module.find_installation(pure: false)
+py_dep = py.dependency()
+
+# Additional targets
+py_with_pytest = py_module.find_installation(required: false, modules: ['pytest'])
+if py_with_pytest.found()
+  test(
+    'pytest', 
+    py_with_pytest, 
+    args: [
+      '-m', 
+      'pytest', 
+      '-c', 
+      meson.current_source_dir() / 'tox.ini', 
+      '--doctest', 
+      meson.current_source_dir() / 'src' / 'sage' / 'categories'
+    ],
+    timeout: 0,
+  )
+endif
+
+subdir('src')

pkgs/sage-conf/_sage_conf/_conf.py.in

@@ -8,6 +8,7 @@ VERSION = "@PACKAGE_VERSION@"
 # to it.
 SAGE_LOCAL = "@prefix@"
 SAGE_ROOT = "@SAGE_ROOT@"
+SAGE_SHARE = "@SAGE_SHARE@"
 
 # The semicolon-separated list of GAP root paths. This is the list of
 # locations that are searched for GAP packages. This is passed directly

pyproject.toml

@@ -0,0 +1,7 @@
+[build-system]
+build-backend = 'mesonpy'
+requires = ['meson-python', 'cython>=3.0.0']
+
+[project]
+name = 'sagemath'
+dynamic = ["version"]

src/doc/en/installation/index.rst

@@ -218,6 +218,7 @@ More information:
    binary
    conda
    source
+   meson
    launching
    troubles
 

src/doc/en/installation/meson.rst

@@ -0,0 +1,107 @@
+.. _build-source-meson:
+
+================================
+Building from source using Meson
+================================
+
+This is a short guide on how to build the Sage from source using Meson.
+
+Walkthrough
+===========
+
+Assume we're starting from a clean repo and a fully set up conda environment::
+
+    ```bash 
+    ./bootstrap-conda
+    mamba env create --file src/environment-dev-3.11.yml --name sage-dev
+    conda activate sage-dev
+    ```
+
+Alternatively, install all build requirements as described in section
+:ref:`section-prereqs`.
+
+.. NOTE::
+
+    If you have previously build Sage in-place, you first have to delete the
+    already compiled files, e.g. with ``shopt -s globstar`` followed by 
+    ``rm src/**/*.so`` or ``for f in src/**/*.so ; do mv "$f" "$f.old"; done``.
+    Also uninstall the 'old' sage packages with ``pip uninstall sage-conf sage-setup sagemath-standard``.
+
+To compile and install the project in editable install, just use::
+
+    ```bash
+    pip install --no-build-isolation --editable .
+    ```
+
+This will install Sage in the current Python environment. You can then start
+Sage from the command line with ``./sage`` or run the tests with ``./sage -t``.
+
+.. NOTE::
+
+    By using ``pip install --editable`` in the above steps, the Sage library 
+    is installed in editable mode. This means that when you only edit source
+    files, there is no need to rebuild the library; it suffices to restart Sage.
+    Note that this even works when you edit Cython files, so you no longer need
+    to manually compile after editing Cython files.
+
+.. NOTE::
+
+    Note that ``make`` is not used at all, nor is ``configure``.
+    This means that any Sage-the-distribution commands such as ``sage -i`` 
+    will not work.
+
+Background information
+======================
+
+Under the hood, pip invokes meson to configure and build the project.
+We can also use meson directly as follows.
+
+To configure the project, we need to run the following command::
+
+    ```bash
+    meson setup builddir --prefix=$PWD/build-install
+    ```
+
+This will create a build directory ``builddir`` that will hold the build artifacts.
+The ``--prefix`` option specifies the directory where the Sage will be installed.
+To compile the project, run the following command::
+
+    ```bash
+    meson compile -C builddir
+    ```
+
+Installing is done with the following command::
+
+    ```bash
+    meson install -C builddir
+    ```
+
+This will then install in the directory specified by ``--prefix``, e.g.
+`build-install/lib/python3.11/site-packages/sage`.
+Usually, this directory is not on your Python path, so you have to use::
+
+    ```bash
+    PYTHONPATH=build-install/lib/python3.11/site-packages ./sage
+    ```
+
+Alternatively, we can still use pip to install::
+
+    ```bash
+    pip install --no-build-isolation --config-settings=builddir=builddir --editable .
+    ```
+
+.. tip::
+
+    Package maintainers may want to specify further build options or need
+    to install to a different directory than the install prefix.
+    Both are supported naturally by Meson::
+
+        ```bash
+        meson setup builddir --prefix=/usr --libdir=... -Dcpp_args=...
+        meson compile -C builddir
+        DESTDIR=/path/to/staging/root meson install -C builddir
+        ```
+
+    See `Meson's quick guide <https://mesonbuild.com/Quick-guide.html#using-meson-as-a-distro-packager>`_
+    and `Meson's install guide <https://mesonbuild.com/Installing.html#destdir-support>`_
+    for more information.

src/doc/en/installation/source.rst

@@ -370,6 +370,12 @@ does not raise an :class:`ImportError`, then it worked.
 Installation steps
 ------------------
 
+.. hint:: 
+
+  The following steps use the classical ``./configure && make`` build
+  process. The modern Meson build system is also supported, see
+  :ref:`build-source-meson`.
+
 #. Follow the procedure in the file `README.md <https://github.com/sagemath/sage/#readme>`_
    in ``SAGE_ROOT``.
 

src/environment-3.10-linux.yml

@@ -361,10 +361,11 @@ dependencies:
   - libxkbcommon=1.6.0=h5d7e998_0
   - matplotlib-inline=0.1.6=pyhd8ed1ab_0
   - memory-allocator=0.1.3=py310h2372a71_0
-  - overrides=7.4.0=pyhd8ed1ab_0
-  - pexpect=4.8.0=pyh1a96a4e_2
-  - pillow=10.1.0=py310h01dd4db_0
-  - pip=23.3.2=pyhd8ed1ab_0
+  - meson=1.3.2=pyhd8ed1ab_0
+  - overrides=7.7.0=pyhd8ed1ab_0
+  - pexpect=4.9.0=pyhd8ed1ab_0
+  - pillow=10.2.0=py310h01dd4db_0
+  - pip=24.0=pyhd8ed1ab_0
   - pplpy=0.8.9=py310h28f6eb6_0
   - primecountpy=0.1.0=py310hd41b1e2_4
   - prompt-toolkit=3.0.42=pyha770c72_0
@@ -400,7 +401,8 @@ dependencies:
   - jsonschema-specifications=2023.11.2=pyhd8ed1ab_0
   - jupyter_server_terminals=0.5.0=pyhd8ed1ab_0
   - liblapacke=3.9.0=20_linux64_openblas
-  - numpy=1.26.2=py310hb13e2d6_0
+  - meson-python=0.15.0=pyh0c530f3_0
+  - numpy=1.26.4=py310hb13e2d6_0
   - prompt_toolkit=3.0.42=hd8ed1ab_0
   - pyqt5-sip=12.12.2=py310hc6cd4ac_5
   - requests=2.31.0=pyhd8ed1ab_0

src/environment-3.10-macos.yml

@@ -299,9 +299,10 @@ dependencies:
   - liblapack=3.9.0=20_osx64_openblas
   - matplotlib-inline=0.1.6=pyhd8ed1ab_0
   - memory-allocator=0.1.3=py310h6729b98_0
-  - overrides=7.4.0=pyhd8ed1ab_0
-  - pexpect=4.8.0=pyh1a96a4e_2
-  - pip=23.3.2=pyhd8ed1ab_0
+  - meson=1.3.2=pyhd8ed1ab_0
+  - overrides=7.7.0=pyhd8ed1ab_0
+  - pexpect=4.9.0=pyhd8ed1ab_0
+  - pip=24.0=pyhd8ed1ab_0
   - pplpy=0.8.9=py310hd89f7aa_0
   - primecountpy=0.1.0=py310h88cfcbd_4
   - prompt-toolkit=3.0.42=pyha770c72_0
@@ -333,7 +334,8 @@ dependencies:
   - jsonschema-specifications=2023.11.2=pyhd8ed1ab_0
   - jupyter_server_terminals=0.5.0=pyhd8ed1ab_0
   - liblapacke=3.9.0=20_osx64_openblas
-  - numpy=1.26.2=py310h2a7ecf2_0
+  - meson-python=0.15.0=pyh0c530f3_0
+  - numpy=1.26.4=py310h4bfa8fc_0
   - pango=1.50.14=h19c1c8a_2
   - prompt_toolkit=3.0.42=hd8ed1ab_0
   - pyobjc-framework-cocoa=10.1=py310h3674b6a_0

src/environment-3.11-linux.yml

@@ -360,10 +360,11 @@ dependencies:
   - libxkbcommon=1.6.0=h5d7e998_0
   - matplotlib-inline=0.1.6=pyhd8ed1ab_0
   - memory-allocator=0.1.3=py311h459d7ec_0
-  - overrides=7.4.0=pyhd8ed1ab_0
-  - pexpect=4.8.0=pyh1a96a4e_2
-  - pillow=10.1.0=py311ha6c5da5_0
-  - pip=23.3.2=pyhd8ed1ab_0
+  - meson=1.3.2=pyhd8ed1ab_0
+  - overrides=7.7.0=pyhd8ed1ab_0
+  - pexpect=4.9.0=pyhd8ed1ab_0
+  - pillow=10.2.0=py311ha6c5da5_0
+  - pip=24.0=pyhd8ed1ab_0
   - pplpy=0.8.9=py311h85abca9_0
   - primecountpy=0.1.0=py311h9547e67_4
   - prompt-toolkit=3.0.42=pyha770c72_0
@@ -399,7 +400,8 @@ dependencies:
   - jsonschema-specifications=2023.11.2=pyhd8ed1ab_0
   - jupyter_server_terminals=0.5.0=pyhd8ed1ab_0
   - liblapacke=3.9.0=20_linux64_openblas
-  - numpy=1.26.2=py311h64a7726_0
+  - meson-python=0.15.0=pyh0c530f3_0
+  - numpy=1.26.4=py311h64a7726_0
   - prompt_toolkit=3.0.42=hd8ed1ab_0
   - pyqt5-sip=12.12.2=py311hb755f60_5
   - requests=2.31.0=pyhd8ed1ab_0

src/environment-3.11-macos.yml

@@ -298,9 +298,10 @@ dependencies:
   - liblapack=3.9.0=20_osx64_openblas
   - matplotlib-inline=0.1.6=pyhd8ed1ab_0
   - memory-allocator=0.1.3=py311h2725bcf_0
-  - overrides=7.4.0=pyhd8ed1ab_0
-  - pexpect=4.8.0=pyh1a96a4e_2
-  - pip=23.3.2=pyhd8ed1ab_0
+  - meson=1.3.2=pyhd8ed1ab_0
+  - overrides=7.7.0=pyhd8ed1ab_0
+  - pexpect=4.9.0=pyhd8ed1ab_0
+  - pip=24.0=pyhd8ed1ab_0
   - pplpy=0.8.9=py311h7355a2a_0
   - primecountpy=0.1.0=py311h5fe6e05_4
   - prompt-toolkit=3.0.42=pyha770c72_0
@@ -332,7 +333,8 @@ dependencies:
   - jsonschema-specifications=2023.11.2=pyhd8ed1ab_0
   - jupyter_server_terminals=0.5.0=pyhd8ed1ab_0
   - liblapacke=3.9.0=20_osx64_openblas
-  - numpy=1.26.2=py311h93c810c_0
+  - meson-python=0.15.0=pyh0c530f3_0
+  - numpy=1.26.4=py311hc43a94b_0
   - pango=1.50.14=h19c1c8a_2
   - prompt_toolkit=3.0.42=hd8ed1ab_0
   - pyobjc-framework-cocoa=10.1=py311h9b70068_0