Merge pull request #7 from JakubBlaha/master

Test + README note on the += operator (list)

Author: Code0x58

README.rst

@@ -59,6 +59,25 @@ Basics
     assert store.a_dictionary['new_value'] == "old value"
     assert store.a_dictionary is not store.a_dictionary
 
+    # Appending to, extending a list
+    >>> store.list = [1, 2, 3]
+
+    # Because of the fact that .append won't modify the list in the actual file,
+    # but only a copy...
+    >>> store.list.append(4)
+    >>> store.list
+    [1, 2, 3]
+
+    # ... we need to rather use the += operator to append to a list.
+    >>> store.list += [4]
+    >>> store.list
+    [1, 2, 3, 4]
+
+    # Similarly, we can extend the list
+    >>> store.list += [5, 6]
+    >>> store.list
+    [1, 2, 3, 4, 5, 6]
+
 Transactions
 ~~~~~~~~~~~~
 

test_jsonstore.py

@@ -284,6 +284,18 @@ def test_transaction_write(self):
         with open(self._store_file) as handle:
             self.assertEqual(handle.read(), '{"value1": 1, "value2": 2}')
 
+    def test_list_concat_inplace(self):
+        self.store.list = []
+        extension = [{"key": "value"}]
+
+        # make sure += happens
+        self.store["list"] += extension
+        self.store.list += extension
+        self.assertEqual(self.store.list, extension * 2)
+
+        # make sure a deepcopy occurred
+        self.assertIsNot(self.store.list[0], extension[0])
+
 
 if __name__ == "__main__":
     unittest.main()