[3.8] bpo-42531: Teach importlib.resources.path to handle packages without __file__ (GH-23611)

Fixes [bpo-42531]() for Python 3.8.

The issue also applies to 3.7. If this PR looks like it'll be accepted, I can cherry-pick it to the 3.7 branch and submit a follow-up PR.

Automerge-Triggered-By: GH:jaraco

1 files changed, 12 insertions, 0 deletions

diff --git a/Lib/test/test_importlib/test_path.py b/Lib/test/test_importlib/test_path.py
index 2d3dcda..5c5a8e3 100644
--- a/Lib/test/test_importlib/test_path.py
+++ b/Lib/test/test_importlib/test_path.py
@@ -1,3 +1,4 @@
+import io
 import unittest
 
 from importlib import resources
@@ -27,6 +28,17 @@ class PathDiskTests(PathTests, unittest.TestCase):
     data = data01
 
 
+class PathMemoryTests(PathTests, unittest.TestCase):
+    def setUp(self):
+        file = io.BytesIO(b'Hello, UTF-8 world!\n')
+        self.addCleanup(file.close)
+        self.data = util.create_package(
+            file=file, path=FileNotFoundError("package exists only in memory")
+        )
+        self.data.__spec__.origin = None
+        self.data.__spec__.has_location = False
+
+
 class PathZipTests(PathTests, util.ZipSetup, unittest.TestCase):
     def test_remove_in_context_manager(self):
         # It is not an error if the file that was temporarily stashed on the