unit test

src/pip/_internal/download.py

@@ -936,18 +936,20 @@ def unpack_file_url(
     link_path = url_to_path(link.url_without_fragment)
     # If it's a url to a local directory
     if is_dir_url(link):
+
+        def ignore(d, names):
+            # Pulling in those directories can potentially
+            # be very slow.
+            # see discussion at:
+            #   https://github.com/pypa/pip/pull/6770
+            return ['.tox', '.nox'] if d == link_path else []
+
         if os.path.isdir(location):
             rmtree(location)
         shutil.copytree(link_path,
                         location,
                         symlinks=True,
-                        # Pulling in those directories can potentially
-                        # be very slow.
-                        # see discussion at:
-                        #   https://github.com/pypa/pip/pull/6770
-                        #   https://github.com/pypa/pip/issues/2195
-                        #   https://github.com/pypa/pip/pull/2196
-                        ignore=shutil.ignore_patterns('.tox', '.nox'))
+                        ignore=ignore)
 
         if download_dir:
             logger.info('Link is a directory, ignoring download_dir')

tests/unit/test_download.py

@@ -413,6 +413,50 @@ class Test_unpack_file_url(object):
         assert os.path.isdir(os.path.join(self.build_dir, 'fspkg'))
 
 
+@pytest.mark.parametrize('exclude_dir', [
+    '.nox',
+    '.tox'
+])
+def test_unpack_file_url_with_excluded_dirs(exclude_dir):
+
+    def touch(path):
+        with open(path, 'a'):
+            os.utime(path, None)
+
+    src_dir = mkdtemp()
+    src_included_file = os.path.join(src_dir, 'file.txt')
+    src_excluded_dir = os.path.join(src_dir, exclude_dir)
+    src_excluded_file = os.path.join(src_dir, exclude_dir, 'file.txt')
+    src_included_dir = os.path.join(src_dir, 'subdir', exclude_dir)
+
+    # set up source directory
+    os.makedirs(src_excluded_dir, exist_ok=True)
+    os.makedirs(src_included_dir, exist_ok=True)
+    touch(src_included_file)
+    touch(src_excluded_file)
+
+    dst_dir = mkdtemp()
+    dst_included_file = os.path.join(dst_dir, 'file.txt')
+    dst_excluded_dir = os.path.join(dst_dir, exclude_dir)
+    dst_excluded_file = os.path.join(dst_dir, exclude_dir, 'file.txt')
+    dst_included_dir = os.path.join(dst_dir, 'subdir', exclude_dir)
+
+    try:
+        src_link = Link(path_to_url(src_dir))
+        unpack_file_url(
+            src_link,
+            dst_dir,
+            download_dir=None
+        )
+        assert not os.path.isdir(dst_excluded_dir)
+        assert not os.path.isfile(dst_excluded_file)
+        assert os.path.isfile(dst_included_file)
+        assert os.path.isdir(dst_included_dir)
+    finally:
+        rmtree(src_dir)
+        rmtree(dst_dir)
+
+
 class TestSafeFileCache:
     """
     The no_perms test are useless on Windows since SafeFileCache uses