[azure] Fix collectstatic --clear (#1403)

storages/backends/azure_storage.py

@@ -268,6 +268,9 @@ def get_available_name(self, name, max_length=_AZURE_NAME_MAX_LEN):
         return super().get_available_name(name, max_length)
 
     def exists(self, name):
+        if not name:
+            return True
+
         blob_client = self.client.get_blob_client(self._get_valid_path(name))
         return blob_client.exists()
 
@@ -390,16 +393,9 @@ def list_all(self, path=""):
 
     def listdir(self, path=""):
         """
-        Return directories and files for a given path.
-        Leave the path empty to list the root.
-        Order of dirs and files is undefined.
+        Return all files for a given path.
+        Given that Azure can't return paths it only returns files.
+        Works great for our little adventure.
         """
-        files = []
-        dirs = set()
-        for name in self.list_all(path):
-            n = name[len(path) :]
-            if "/" in n:
-                dirs.add(n.split("/", 1)[0])
-            else:
-                files.append(n)
-        return list(dirs), files
+
+        return [], self.list_all(path)

tests/test_azure.py

@@ -388,46 +388,15 @@ def test_storage_listdir_base(self):
         )
         self.storage._custom_client.list_blobs.assert_not_called()
 
-        self.assertEqual(len(dirs), 2)
-        for directory in ["some", "other"]:
-            self.assertTrue(
-                directory in dirs,
-                """ "{}" not in directory list "{}".""".format(directory, dirs),
-            )
+        self.assertEqual(len(dirs), 0)
 
-        self.assertEqual(len(files), 2)
-        for filename in ["2.txt", "4.txt"]:
+        self.assertEqual(len(files), 4)
+        for filename in ["2.txt", "4.txt", "other/path/3.txt", "some/path/1.txt"]:
             self.assertTrue(
                 filename in files,
                 """ "{}" not in file list "{}".""".format(filename, files),
             )
 
-    def test_storage_listdir_subdir(self):
-        file_names = ["some/path/1.txt", "some/2.txt"]
-
-        result = []
-        for p in file_names:
-            obj = mock.MagicMock()
-            obj.name = p
-            result.append(obj)
-        self.storage._client.list_blobs.return_value = iter(result)
-        self.storage._custom_client.list_blobs.assert_not_called()
-
-        dirs, files = self.storage.listdir("some/")
-        self.storage._client.list_blobs.assert_called_with(
-            name_starts_with="some/", timeout=20
-        )
-
-        self.assertEqual(len(dirs), 1)
-        self.assertTrue(
-            "path" in dirs, """ "path" not in directory list "{}".""".format(dirs)
-        )
-
-        self.assertEqual(len(files), 1)
-        self.assertTrue(
-            "2.txt" in files, """ "2.txt" not in files list "{}".""".format(files)
-        )
-
     def test_size_of_file(self):
         props = BlobProperties()
         props.size = 12