ENH: Add support for targeting Android

Author: mhsmith

mesonpy/__init__.py

@@ -744,6 +744,27 @@ def __init__(
                     self._meson_cross_file.write_text(cross_file_data, encoding='utf-8')
                     self._meson_args['setup'].extend(('--cross-file', os.fspath(self._meson_cross_file)))
 
+        # Android requires cross compilation: synthesize the appropriate cross file.
+        elif sysconfig.get_platform().startswith('android-'):
+            cross_file_data = textwrap.dedent(f'''
+                # Binaries are controlled by environment variables, so they don't need
+                # to be repeated here.
+                [host_machine]
+                system = 'android'
+                subsystem = 'android'
+                kernel = 'linux'
+                cpu = {platform.machine()!r}
+                cpu_family = {platform.machine()!r}
+                endian = {sys.byteorder!r}
+
+                [properties]
+                # cibuildwheel's cross virtual environment will make Meson believe it's
+                # running on Android when it's actually running on Linux or macOS.
+                needs_exe_wrapper = true
+            ''')
+            self._meson_cross_file.write_text(cross_file_data, encoding='utf-8')
+            self._meson_args['setup'].extend(('--cross-file', os.fspath(self._meson_cross_file)))
+
         # Support iOS targets. iOS does not have native build tools and always
         # requires cross compilation: synthesize the appropriate cross file.
         elif sysconfig.get_platform().startswith('ios-'):

tests/test_project.py

@@ -378,6 +378,34 @@ def test_archflags_envvar_parsing_invalid(package_purelib_and_platlib, monkeypat
         os.environ.pop('_PYTHON_HOST_PLATFORM', None)
 
 
+def test_android_project(package_simple, monkeypatch, tmp_path):
+    # Mock being on Android
+    monkeypatch.setattr(sys, 'platform', 'android')
+    monkeypatch.setattr(sys, 'byteorder', 'little')
+    monkeypatch.setattr(platform, 'machine', Mock(return_value='aarch64'))
+    monkeypatch.setattr(sysconfig, 'get_platform', Mock(return_value='android-24-arm64_v8a'))
+    monkeypatch.setenv('STRIP', '/path/to/strip')
+
+    # Create a project.
+    project = mesonpy.Project(source_dir=package_simple, build_dir=tmp_path)
+
+    # Meson configuration points at the cross file
+    assert project._meson_args['setup'][-2:] == ['--cross-file', os.fspath(tmp_path / 'meson-python-cross-file.ini')]
+
+    # Meson config files exist, and have some relevant keys
+    assert (tmp_path / 'meson-python-native-file.ini').exists()
+    assert (tmp_path / 'meson-python-cross-file.ini').exists()
+
+    cross_config = (tmp_path / 'meson-python-cross-file.ini').read_text().splitlines()
+    assert "system = 'android'" in cross_config
+    assert "subsystem = 'android'" in cross_config
+    assert "kernel = 'linux'" in cross_config
+    assert "cpu = 'aarch64'" in cross_config
+    assert "cpu_family = 'aarch64'" in cross_config
+    assert "endian = 'little'" in cross_config
+    assert 'needs_exe_wrapper = true' in cross_config
+
+
 @pytest.mark.skipif(sys.version_info < (3, 13), reason='requires Python 3.13 or higher')
 @pytest.mark.parametrize('multiarch', [
     'arm64-iphoneos',