ENH: add support for dynamic dependencies computation

Author: dnicolodi

mesonpy/__init__.py

@@ -41,6 +41,15 @@
 else:
     import tomllib
 
+
+if sys.version_info < (3, 8):
+    import importlib_metadata
+else:
+    import importlib.metadata as importlib_metadata
+
+
+import packaging.requirements
+import packaging.version
 import pyproject_metadata
 
 import mesonpy._compat
@@ -658,10 +667,32 @@ def build_editable(self, directory: Path, verbose: bool = False) -> pathlib.Path
         return wheel_file
 
 
+class MesonpyVersion(packaging.version.Version):
+    def __getitem__(self, key):
+        return self.release[key]
+
+
+class _parse_version(version: str) -> Union[packaging.version.LegacyVersion, MesonpyVersion]:
+    try:
+        return MesonpyVersion(version)
+    except packaging.version.InvalidVersion:
+        return packaging.version.LegacyVersion(version)
+
+
+def _compute_dynamic_dependencies(templates) -> List[str]:
+    dependencies = []
+    for template in templates:
+        req = packaging.requirements.Requirement(template)
+        version = _parse_version(importlib_metadata.version(req.name))
+        dependencies.append(template.format(v=version))
+    return dependencies
+
+
 class Project():
     """Meson project wrapper to generate Python artifacts."""
 
     _ALLOWED_DYNAMIC_FIELDS: ClassVar[List[str]] = [
+        'dependencies',
         'version',
     ]
     _metadata: Optional[pyproject_metadata.StandardMetadata]
@@ -778,6 +809,10 @@ def __init__(  # noqa: C901
         if self._metadata and 'version' in self._metadata.dynamic:
             self._metadata.version = self.version
 
+        if self._metadata and 'dependencies' in self._metadata.dynamic:
+            self._metadata.dependencies = _compute_dynamic_dependencies(
+                self._get_config_key('dynamic').get('dependencies', []))
+
     def _get_config_key(self, key: str) -> Any:
         value: Any = self._config
         for part in f'tool.meson-python.{key}'.split('.'):

pyproject.toml

@@ -7,6 +7,7 @@ build-backend = 'mesonpy'
 backend-path = ['.']
 requires = [
   'meson>=0.63.3',
+  'packaging',
   'pyproject-metadata>=0.7.1',
   'tomli>=1.0.0; python_version<"3.11"',
 ]
@@ -29,6 +30,7 @@ classifiers = [
 dependencies = [
   'colorama; os_name == "nt"',
   'meson>=0.63.3',
+  'packaging',
   'pyproject-metadata>=0.7.1',
   'tomli>=1.0.0; python_version<"3.11"',
 ]

tests/packages/dynamic-dependencies/meson.build

@@ -0,0 +1,5 @@
+# SPDX-FileCopyrightText: 2023 The meson-python developers
+#
+# SPDX-License-Identifier: MIT
+
+project('dynamic-dependencies', version: '1.0.0')

tests/packages/dynamic-dependencies/pyproject.toml

@@ -0,0 +1,20 @@
+# SPDX-FileCopyrightText: 2023 The meson-python developers
+#
+# SPDX-License-Identifier: MIT
+
+[build-system]
+build-backend = 'mesonpy'
+requires = ['meson-python']
+
+[project]
+name = 'dynamic-dependencies'
+version = '1.0.0'
+dynamic = [
+  'dependencies',
+]
+
+[tool.meson-python.dynamic]
+dependencies = [
+  'meson ~= {v.major}.{v.minor}',
+  'meson-python >= {v}',
+]

tests/packages/unsupported-dynamic/pyproject.toml

@@ -10,5 +10,5 @@ requires = ['meson-python']
 name = 'unsupported-dynamic'
 version = '1.0.0'
 dynamic = [
-    'dependencies',
+    'requires-python',
 ]

tests/test_project.py

@@ -39,7 +39,7 @@ def test_version(package):
 
 
 def test_unsupported_dynamic(package_unsupported_dynamic):
-    with pytest.raises(mesonpy.MesonBuilderError, match='Unsupported dynamic fields: "dependencies"'):
+    with pytest.raises(mesonpy.MesonBuilderError, match='Unsupported dynamic fields: "requires-python"'):
         with mesonpy.Project.with_temp_working_dir():
             pass