mesonpy: error out if we are running on an unsupported interpreter

Fixes #69

Signed-off-by: Filipe Laíns <lains@riseup.net>

mesonpy/__init__.py

@@ -384,16 +384,8 @@ def __init__(
             )
             self._metadata = None
 
-        # check for unsupported dynamic fields
         if self._metadata:
-            unsupported_dynamic = {
-                key for key in self._metadata.dynamic
-                if key not in self._ALLOWED_DYNAMIC_FIELDS
-            }
-            if unsupported_dynamic:
-                raise MesonBuilderError('Unsupported dynamic fields: {}'.format(
-                    ', '.join(unsupported_dynamic)),
-                )
+            self._validate_metadata()
 
         # make sure the build dir exists
         self._build_dir.mkdir(exist_ok=True)
@@ -458,6 +450,29 @@ def _configure(self, reconfigure: bool = False) -> None:
             else:
                 raise
 
+    def _validate_metadata(self) -> None:
+        assert self._metadata
+
+        # check for unsupported dynamic fields
+        unsupported_dynamic = {
+            key for key in self._metadata.dynamic
+            if key not in self._ALLOWED_DYNAMIC_FIELDS
+        }
+        if unsupported_dynamic:
+            raise MesonBuilderError('Unsupported dynamic fields: {}'.format(
+                ', '.join(unsupported_dynamic)),
+            )
+
+        # check if we are running on an unsupported interpreter
+        if (
+            self._metadata.requires_python
+            and platform.python_version() not in self._metadata.requires_python
+        ):
+            raise MesonBuilderError(
+                f'Unsupported Python version `{platform.python_version()}`, '
+                f'expected `{self._metadata.requires_python}`'
+            )
+
     @functools.lru_cache(maxsize=None)
     def build(self) -> None:
         self._meson('compile')

tests/packages/full-metadata/pyproject.toml

@@ -7,7 +7,7 @@ name = 'full-metadata'
 version = '1.2.3'
 description = 'Some package with all of the PEP 621 metadata'
 readme = 'README.md'
-requires-python = '>=3.10'
+requires-python = '>=3.7'
 license = {file = 'LICENSE'}
 keywords = ['full', 'metadata']
 authors = [

tests/packages/unsupported-python-version/meson.build

@@ -0,0 +1,4 @@
+project(
+    'unsupported-python-version',
+    version: '1.0.0',
+)

tests/packages/unsupported-python-version/pyproject.toml

@@ -0,0 +1,8 @@
+[build-system]
+build-backend = 'mesonpy'
+requires = ['meson-python']
+
+[project]
+name = 'unsupported-python-version'
+version = '1.2.3'
+requires-python = '==1.0.0'

tests/test_metadata.py

@@ -33,7 +33,7 @@ def test_pep621(sdist_full_metadata):
         Project-URL: Documentation, https://readthedocs.org
         Project-URL: Repository, https://github.com/FFY00/mesonpy
         Project-URL: Changelog, https://github.com/FFY00/mesonpy/blob/master/CHANGELOG.md
-        Requires-Python: >=3.10
+        Requires-Python: >=3.7
         Requires-Dist: a
         Requires-Dist: b>1
         Requires-Dist: c>2; os_name != "nt"

tests/test_project.py

@@ -1,5 +1,7 @@
 # SPDX-License-Identifier: EUPL-1.2
 
+import platform
+
 import pytest
 
 import mesonpy
@@ -35,3 +37,12 @@ def test_unsupported_dynamic(package_unsupported_dynamic):
     with pytest.raises(mesonpy.MesonBuilderError, match='Unsupported dynamic fields: dependencies'):
         with mesonpy.Project.with_temp_working_dir():
             pass
+
+
+def test_unsupported_python_version(package_unsupported_python_version):
+    with pytest.raises(mesonpy.MesonBuilderError, match=(
+        f'Unsupported Python version `{platform.python_version()}`, '
+        'expected `==1.0.0`'
+    )):
+        with mesonpy.Project.with_temp_working_dir():
+            pass