Fix race condition with forked monorepos

src/poetry/installation/executor.py

@@ -33,6 +33,7 @@
 from poetry.utils.helpers import remove_directory
 from poetry.utils.isolated_build import IsolatedBuildError
 from poetry.utils.isolated_build import IsolatedBuildInstallError
+from poetry.vcs.git import Git
 
 
 if TYPE_CHECKING:
@@ -46,6 +47,12 @@
     from poetry.utils.env import Env
 
 
+def _package_get_name(package: Package) -> str | None:
+    if url := package.repository_url:
+        return Git.get_name_from_source_url(url)
+    return None
+
+
 class Executor:
     def __init__(
         self,
@@ -167,8 +174,9 @@ def execute(self, operations: list[Operation]) -> int:
                 if is_parallel_unsafe:
                     serial_operations.append(operation)
                 elif operation.package.source_type == "git":
-                    # Git operations on the same repository should be executed serially
-                    serial_git_operations[operation.package.source_url].append(
+                    # Serially execute git operations that get cloned to the same directory,
+                    # to prevent multiple parallel git operations in the same repo.
+                    serial_git_operations[_package_get_name(operation.package)].append(
                         operation
                     )
                 else:
@@ -604,8 +612,6 @@ def _prepare_archive(
         )
 
     def _prepare_git_archive(self, operation: Install | Update) -> Path:
-        from poetry.vcs.git import Git
-
         package = operation.package
         assert package.source_url is not None
 

tests/fixtures/git/github.com/forked_demo/subdirectories/one-copy/pyproject.toml

@@ -0,0 +1,13 @@
+[tool.poetry]
+name = "one"
+version = "1.0.0"
+description = "Some description."
+authors = []
+license = "MIT"
+
+[tool.poetry.dependencies]
+python = "^3.7"
+
+[build-system]
+requires = ["poetry-core>=1.0.0"]
+build-backend = "poetry.core.masonry.api"

tests/fixtures/git/github.com/forked_demo/subdirectories/one/pyproject.toml

@@ -0,0 +1,13 @@
+[tool.poetry]
+name = "one"
+version = "1.0.0"
+description = "Some description."
+authors = []
+license = "MIT"
+
+[tool.poetry.dependencies]
+python = "^3.7"
+
+[build-system]
+requires = ["poetry-core>=1.0.0"]
+build-backend = "poetry.core.masonry.api"

tests/fixtures/git/github.com/forked_demo/subdirectories/two/pyproject.toml

@@ -0,0 +1,13 @@
+[tool.poetry]
+name = "two"
+version = "2.0.0"
+description = "Some description."
+authors = []
+license = "MIT"
+
+[tool.poetry.dependencies]
+python = "~2.7 || ^3.4"
+
+[build-system]
+requires = ["poetry-core>=1.0.0"]
+build-backend = "poetry.core.masonry.api"

tests/helpers.py

@@ -113,7 +113,8 @@ def mock_clone(
     if not source_root:
         source_root = Path(Config.create().get("cache-dir")) / "src"
 
-    dest = source_root / path
+    assert parsed.name is not None
+    dest = source_root / parsed.name
     dest.mkdir(parents=True, exist_ok=True)
 
     copy_path(folder, dest)

tests/installation/test_executor.py

@@ -1091,7 +1091,7 @@ def test_executor_should_append_subdirectory_for_git(
     executor.execute([Install(package)])
 
     archive_arg = spy.call_args[0][0]
-    assert archive_arg == tmp_venv.path / "src/demo/subdirectories/two"
+    assert archive_arg == tmp_venv.path / "src/subdirectories/two"
 
 
 def test_executor_should_install_multiple_packages_from_same_git_repository(
@@ -1131,10 +1131,52 @@ def test_executor_should_install_multiple_packages_from_same_git_repository(
     executor.execute([Install(package_a), Install(package_b)])
 
     archive_arg = spy.call_args_list[0][0][0]
-    assert archive_arg == tmp_venv.path / "src/demo/subdirectories/package_a"
+    assert archive_arg == tmp_venv.path / "src/subdirectories/package_a"
 
     archive_arg = spy.call_args_list[1][0][0]
-    assert archive_arg == tmp_venv.path / "src/demo/subdirectories/package_b"
+    assert archive_arg == tmp_venv.path / "src/subdirectories/package_b"
+
+
+def test_executor_should_install_multiple_packages_from_forked_git_repository(
+    mocker: MockerFixture,
+    tmp_venv: VirtualEnv,
+    pool: RepositoryPool,
+    config: Config,
+    artifact_cache: ArtifactCache,
+    io: BufferedIO,
+    wheel: Path,
+) -> None:
+    package_a = Package(
+        "one",
+        "1.0.0",
+        source_type="git",
+        source_reference="master",
+        source_resolved_reference="123456",
+        source_url="https://github.com/demo/subdirectories.git",
+        source_subdirectory="one",
+    )
+    package_b = Package(
+        "two",
+        "2.0.0",
+        source_type="git",
+        source_reference="master",
+        source_resolved_reference="123456",
+        source_url="https://github.com/forked_demo/subdirectories.git",
+        source_subdirectory="two",
+    )
+
+    chef = Chef(artifact_cache, tmp_venv, Factory.create_pool(config))
+    chef.set_directory_wheel(wheel)
+    prepare_spy = mocker.spy(chef, "prepare")
+
+    executor = Executor(tmp_venv, pool, config, io)
+    executor._chef = chef
+    executor.execute([Install(package_a), Install(package_b)])
+
+    # Verify that the repo for package_a is not re-used for package_b.
+    # both repos must be cloned serially into separate directories.
+    # If so, executor.prepare() will be called twice.
+    assert prepare_spy.call_count == 2
 
 
 def test_executor_should_write_pep610_url_references_for_git_with_subdirectories(