Remove StockMessage.action_by_contact() (#3518)

Use separate strings for "... by me" and "... by contact"
to make them easier to translate.

python/src/deltachat/message.py

@@ -507,6 +507,8 @@ def parse_system_add_remove(text):
 
     returns a (action, affected, actor) triple"""
 
+    # You removed member a@b.
+    # You added member a@b.
     # Member Me (x@y) removed by a@b.
     # Member x@y added by a@b
     # Member With space (tmp1@x.org) removed by tmp2@x.org.
@@ -518,6 +520,10 @@ def parse_system_add_remove(text):
     if m:
         affected, action, actor = m.groups()
         return action, extract_addr(affected), extract_addr(actor)
+    m = re.match(r"you (removed|added) member (.+)", text)
+    if m:
+        action, affected = m.groups()
+        return action, extract_addr(affected), "me"
     if text.startswith("group left by "):
         addr = extract_addr(text[13:])
         if addr:

python/tests/test_3_offline.py

@@ -301,7 +301,7 @@ class TestOfflineChat:
         assert d["draft"] == "" if chat.get_draft() is None else chat.get_draft()
 
     def test_group_chat_creation_with_translation(self, ac1):
-        ac1.set_stock_translation(const.DC_STR_MSGGRPNAME, "abc %1$s xyz %2$s")
+        ac1.set_stock_translation(const.DC_STR_GROUP_NAME_CHANGED_BY_YOU, "abc %1$s xyz %2$s")
         ac1._evtracker.consume_events()
         with pytest.raises(ValueError):
             ac1.set_stock_translation(const.DC_STR_FILE, "xyz %1$s")
@@ -317,7 +317,7 @@ class TestOfflineChat:
         chat.send_text("Now we have a group for homework")
         assert chat.is_promoted()
         chat.set_name("Homework")
-        assert chat.get_messages()[-1].text == "abc homework xyz Homework by me."
+        assert chat.get_messages()[-1].text == "abc homework xyz Homework"
 
     @pytest.mark.parametrize("verified", [True, False])
     def test_group_chat_qr(self, acfactory, ac1, verified):