Add first functional version of the plugin module

tox_poetry_installer.py

@@ -0,0 +1,78 @@
+from pathlib import Path
+import logging
+from typing import Dict, List
+
+from poetry.factory import Factory
+from poetry.factory import Poetry
+from poetry.packages import Package
+from poetry.installation.pip_installer import PipInstaller
+from poetry.io.null_io import NullIO
+from poetry.utils.env import VirtualEnv
+
+from tox.action import Action as ToxAction
+from tox.venv import VirtualEnv as ToxVirtualEnv
+from tox import hookimpl
+
+
+__title__ = "tox-poetry-installer"
+__summary__ = "Tox plugin to install Tox environment dependencies using the Poetry backend and lockfile"
+__version__ = "0.1.0"
+__url__ = "https://github.com/enpaul/tox-poetry-installer/"
+__license__ = "MIT"
+__authors__ = ["Ethan Paul <e@enp.one>"]
+
+
+def _make_poetry(venv: ToxVirtualEnv) -> Poetry:
+    return Factory().create_poetry(venv.envconfig.config.toxinidir)
+
+
+def _find_locked_dependencies(poetry: Poetry, dependency_name: str) -> List[Package]:
+    packages: Dict[str, Package] = {
+        package.name: package
+        for package in poetry.locker.locked_repository(True).packages
+    }
+
+    try:
+        top_level = packages[dependency_name]
+    except KeyError:
+        raise
+
+    def find_transients(name: str) -> List[Package]:
+        transients = [packages[name]]
+        for dep in packages[name].requires:
+            transients += find_transients(dep.name)
+        return transients
+
+    return find_transients(top_level.name)
+
+
+@hookimpl
+def tox_testenv_install_deps(venv: ToxVirtualEnv, action: ToxAction):
+
+    logger = logging.getLogger(__name__)
+
+    if action.name == venv.envconfig.config.isolated_build_env:
+        logger.debug(f"Environment {action.name} is isolated build environment; skipping Poetry-based dependency installation")
+        return None
+
+    poetry = _make_poetry(venv)
+
+    logger.debug(f"Loaded project pyproject.toml from {poetry.file}")
+
+    dependencies = []
+    for env_dependency in venv.envconfig.deps:
+        dependencies += _find_locked_dependencies(poetry, env_dependency.name)
+
+    logger.debug(f"Identified {len(dependencies)} dependencies for environment {action.name}")
+
+    installer = PipInstaller(
+        env=VirtualEnv(path=Path(venv.envconfig.envdir)),
+        io=NullIO(),
+        pool=poetry.pool
+    )
+
+    for dependency in dependencies:
+        logger.info(f"Installing environment dependency: {dependency}")
+        installer.install(dependency)
+
+    return dependencies