1 files changed, 53 insertions, 2 deletions
diff --git a/setuptools/tests/fixtures.py b/setuptools/tests/fixtures.py
index 5204c8d1..a5a172e0 100644
--- a/setuptools/tests/fixtures.py
+++ b/setuptools/tests/fixtures.py
@@ -1,9 +1,14 @@
+import contextlib
+import sys
+import shutil
+import subprocess
+
 import pytest
 
 from . import contexts
 
 
-@pytest.yield_fixture
+@pytest.fixture
 def user_override(monkeypatch):
     """
     Override site.USER_BASE and site.USER_SITE with temporary directories in
@@ -17,7 +22,53 @@ def user_override(monkeypatch):
                 yield
 
 
-@pytest.yield_fixture
+@pytest.fixture
 def tmpdir_cwd(tmpdir):
     with tmpdir.as_cwd() as orig:
         yield orig
+
+
+@pytest.fixture
+def tmp_src(request, tmp_path):
+    """Make a copy of the source dir under `$tmp/src`.
+
+    This fixture is useful whenever it's necessary to run `setup.py`
+    or `pip install` against the source directory when there's no
+    control over the number of simultaneous invocations. Such
+    concurrent runs create and delete directories with the same names
+    under the target directory and so they influence each other's runs
+    when they are not being executed sequentially.
+    """
+    tmp_src_path = tmp_path / 'src'
+    shutil.copytree(request.config.rootdir, tmp_src_path)
+    return tmp_src_path
+
+
+@pytest.fixture(autouse=True, scope="session")
+def workaround_xdist_376(request):
+    """
+    Workaround pytest-dev/pytest-xdist#376
+
+    ``pytest-xdist`` tends to inject '' into ``sys.path``,
+    which may break certain isolation expectations.
+    Remove the entry so the import
+    machinery behaves the same irrespective of xdist.
+    """
+    if not request.config.pluginmanager.has_plugin('xdist'):
+        return
+
+    with contextlib.suppress(ValueError):
+        sys.path.remove('')
+
+
+@pytest.fixture
+def sample_project(tmp_path):
+    """
+    Clone the 'sampleproject' and return a path to it.
+    """
+    cmd = ['git', 'clone', 'https://github.com/pypa/sampleproject']
+    try:
+        subprocess.check_call(cmd, cwd=str(tmp_path))
+    except Exception:
+        pytest.skip("Unable to clone sampleproject")
+    return tmp_path / 'sampleproject'