Wrap the test data in a helper that will copy to the tmpdir

This is needed because the various activities that exericsing the
tests do will cause files to change inside this data directory. If
we do not make it test specific then we run into concurrency issues.

tests/conftest.py

@@ -3,6 +3,7 @@ import shutil
 import py
 import pytest
 
+from tests.lib import TestData
 from tests.lib.path import Path
 from tests.lib.scripttest import PipTestEnvironment
 from tests.lib.venv import VirtualEnvironment
@@ -67,3 +68,8 @@ def script(tmpdir, virtualenv):
         capture_temp=True,
         assert_no_temp=True,
     )
+
+
+@pytest.fixture
+def data(tmpdir):
+    return TestData.copy(tmpdir.join("data"))

tests/lib/__init__.py

@@ -4,28 +4,18 @@ from __future__ import absolute_import
 import os
 import sys
 import re
-import atexit
 import textwrap
 import site
 
 import scripttest
 import virtualenv
 
-from pip.backwardcompat import uses_pycache
-
 from tests.lib.path import Path, curdir, u
 
+DATA_DIR = Path(__file__).folder.folder.join("data").abspath
 
 pyversion = sys.version[:3]
 pyversion_nodot = "%d%d" % (sys.version_info[0], sys.version_info[1])
-tests_lib = Path(__file__).abspath.folder  # pip/tests/lib
-tests_root = tests_lib.folder  # pip/tests
-tests_cache = os.path.join(tests_root, 'tests_cache')  # pip/tests/tests_cache
-src_folder = tests_root.folder  # pip/
-tests_data = os.path.join(tests_root, 'data')  # pip/tests/data
-packages = os.path.join(tests_data, 'packages')  # pip/tests/data/packages
-
-fast_test_env_root = tests_cache / 'test_ws'
 
 
 def path_to_url(path):
@@ -42,8 +32,59 @@ def path_to_url(path):
         return 'file:///' + drive + url
     return 'file://' + url
 
-find_links = path_to_url(os.path.join(tests_data, 'packages'))
-find_links2 = path_to_url(os.path.join(tests_data, 'packages2'))
+
+class TestData(object):
+    """
+    Represents a bundle of pre-created test data.
+
+    This copies a pristine set of test data into a root location that is
+    designed to be test specific. The reason for this is when running the tests
+    concurrently errors can be generated because the related tooling uses
+    the directory as a work space. This leads to two concurrent processes
+    trampling over each other. This class gets around that by copying all
+    data into a directory and operating on the copied data.
+    """
+
+    def __init__(self, root, source=None):
+        self.source = source or DATA_DIR
+        self.root = Path(root).abspath
+
+    @classmethod
+    def copy(cls, root):
+        obj = cls(root)
+        obj.reset()
+        return obj
+
+    def reset(self):
+        self.root.rmtree()
+        self.source.copytree(self.root)
+
+    @property
+    def packages(self):
+        return self.root.join("packages")
+
+    @property
+    def packages2(self):
+        return self.root.join("packages2")
+
+    @property
+    def indexes(self):
+        return self.root.join("indexes")
+
+    @property
+    def reqfiles(self):
+        return self.root.join("reqfiles")
+
+    @property
+    def find_links(self):
+        return path_to_url(self.packages)
+
+    @property
+    def find_links2(self):
+        return path_to_url(self.packages2)
+
+    def index_url(self, index="simple"):
+        return path_to_url(self.root.join("indexes", index))
 
 
 class TestFailure(AssertionError):
@@ -253,7 +294,9 @@ class PipTestEnvironment(scripttest.TestFileEnvironment):
         return self.run("pip", *args, **kwargs)
 
     def pip_install_local(self, *args, **kwargs):
-        return self.pip("install", "--no-index", "--find-links", find_links,
+        return self.pip(
+            "install", "--no-index",
+            "--find-links", path_to_url(os.path.join(DATA_DIR, "packages")),
             *args, **kwargs
         )
 
@@ -385,10 +428,3 @@ def assert_raises_regexp(exception, reg, run, *args, **kwargs):
         e = sys.exc_info()[1]
         p = re.compile(reg)
         assert p.search(str(e)), str(e)
-
-
-#
-# This cleanup routine ensures that FastTestPipEnvironment doesn't leave an
-# environment hanging around that might confuse the next test run.
-#
-atexit.register(fast_test_env_root.rmtree)