fixes issue s3 iterdir error when path is only the bucket

Author: andrewfulton9

upath/implementations/s3.py

@@ -22,4 +22,5 @@ def _sub_path(self, name):
         so it gets subbed out as well
         """
         sp = self.path
-        return re.sub(f"^{self._url.netloc}/({sp}|{sp[1:]})/", "", name)
+        subed = re.sub(f"^{self._url.netloc}/({sp}|{sp[1:]})/?", "", name)
+        return subed

upath/tests/cases.py

@@ -26,7 +26,6 @@ def test_chmod(self):
         "url, expected", [("file1.txt", True), ("fakefile.txt", False)]
     )
     def test_exists(self, url, expected):
-        print(self.path)
         path = self.path.joinpath(url)
         assert path.exists() == expected
 
@@ -92,9 +91,13 @@ def test_iterdir(self, local_testdir):
         up_iter = list(self.path.iterdir())
         pl_iter = list(pl_path.iterdir())
 
+        for x in up_iter:
+            assert x.exists()
+
         assert len(up_iter) == len(pl_iter)
         pnames = [p.name for p in pl_iter]
         assert all(map(lambda x: x.name in pnames, up_iter))
+        assert next(self.path.parent.iterdir()).exists()
 
     def test_lchmod(self):
         with pytest.raises(NotImplementedError):