1 files changed, 135 insertions, 0 deletions
diff --git a/pw_build/py/pw_build/generate_python_requirements.py b/pw_build/py/pw_build/generate_python_requirements.py
new file mode 100644
index 000000000..3a7bc67fc
--- /dev/null
+++ b/pw_build/py/pw_build/generate_python_requirements.py
@@ -0,0 +1,135 @@
+# Copyright 2022 The Pigweed Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may not
+# use this file except in compliance with the License. You may obtain a copy of
+# the License at
+#
+#     https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations under
+# the License.
+"""Check Python package install_requires are covered."""
+
+import argparse
+import configparser
+from pathlib import Path
+import sys
+
+try:
+    from pw_build.python_package import load_packages
+    from pw_build.create_python_tree import update_config_with_packages
+except ImportError:
+    # Load from python_package from this directory if pw_build is not available.
+    from python_package import load_packages  # type: ignore
+    from create_python_tree import update_config_with_packages  # type: ignore
+
+
+def _parse_args() -> argparse.Namespace:
+    parser = argparse.ArgumentParser(description=__doc__)
+    parser.add_argument(
+        '--python-dep-list-files',
+        type=Path,
+        required=True,
+        help=(
+            'Path to a text file containing the list of Python package '
+            'metadata json files.'
+        ),
+    )
+    parser.add_argument(
+        '--requirement',
+        type=Path,
+        required=True,
+        help='requirement file to generate',
+    )
+    parser.add_argument(
+        '--gn-packages',
+        required=True,
+        help=(
+            'Comma separated list of GN python package '
+            'targets to check for requirements.'
+        ),
+    )
+    parser.add_argument(
+        '--exclude-transitive-deps',
+        action='store_true',
+        help='Exclude checking transitive deps of the specified --gn-packages',
+    )
+    return parser.parse_args()
+
+
+class NoMatchingGnPythonDependency(Exception):
+    """An error occurred while processing a Python dependency."""
+
+
+def main(
+    python_dep_list_files: Path,
+    requirement: Path,
+    gn_packages: str,
+    exclude_transitive_deps: bool,
+) -> int:
+    """Check Python package setup.cfg correctness."""
+
+    # Split the comma separated string and remove leading slashes.
+    gn_target_names = [
+        target.lstrip('/')
+        for target in gn_packages.split(',')
+        if target  # The last target may be an empty string.
+    ]
+    for i, gn_target in enumerate(gn_target_names):
+        # Remove metadata subtarget if present.
+        python_package_target = gn_target.replace('._package_metadata(', '(', 1)
+        # Split on the first paren to ignore the toolchain.
+        gn_target_names[i] = python_package_target.split('(')[0]
+
+    py_packages = load_packages([python_dep_list_files], ignore_missing=False)
+
+    target_py_packages = py_packages
+    if exclude_transitive_deps:
+        target_py_packages = []
+        for pkg in py_packages:
+            valid_target = [
+                target in pkg.gn_target_name for target in gn_target_names
+            ]
+            if not any(valid_target):
+                continue
+            target_py_packages.append(pkg)
+
+    if not target_py_packages:
+        gn_targets_to_include = '\n'.join(gn_target_names)
+        declared_py_deps = '\n'.join(pkg.gn_target_name for pkg in py_packages)
+        raise NoMatchingGnPythonDependency(
+            'No matching GN Python dependency found.\n'
+            'GN Targets to include:\n'
+            f'{gn_targets_to_include}\n\n'
+            'Declared Python Dependencies:\n'
+            f'{declared_py_deps}\n\n'
+        )
+
+    config = configparser.ConfigParser()
+    config['options'] = {}
+    update_config_with_packages(
+        config=config, python_packages=target_py_packages
+    )
+
+    output = (
+        '# Auto-generated requirements.txt from the following packages:\n#\n'
+    )
+    output += '\n'.join(
+        '# ' + pkg.gn_target_name
+        for pkg in sorted(
+            target_py_packages, key=lambda pkg: pkg.gn_target_name
+        )
+    )
+
+    output += config['options']['install_requires']
+    output += '\n'
+    requirement.write_text(output)
+
+    return 0
+
+
+if __name__ == '__main__':
+    sys.exit(main(**vars(_parse_args())))