gitter/slack/hipchat: Remove "subject" from conversions.

We (lexically) remove "subject" from the conversion code.  The
`build_message` helper calls `set_topic_name` under the hood,
so things still have "subject" in the JSON.

There was good code coverage on `build_message`.

tools/linter_lib/custom_check.py

@@ -314,6 +314,7 @@ def build_custom_checkers(by_lang):
          'bad_lines': ['subject="foo"', ' MAX_SUBJECT_LEN'],
          'exclude': FILES_WITH_LEGACY_SUBJECT,
          'include_only': set([
+             'zerver/data_import/',
              'zerver/lib/',
              'zerver/views/'])},
         {'pattern': '^(?!#)@login_required',

zerver/data_import/gitter.py

@@ -181,10 +181,10 @@ def convert_gitter_workspace_messages(gitter_data: GitterDataT, output_dir: str,
             mentioned_user_ids = get_usermentions(message, user_map,
                                                   user_short_name_to_full_name)
             rendered_content = None
-            subject = 'imported from gitter'
+            topic_name = 'imported from gitter'
             user_id = user_map[message['fromUser']['id']]
 
-            zulip_message = build_message(subject, float(message_time), message_id, message['text'],
+            zulip_message = build_message(topic_name, float(message_time), message_id, message['text'],
                                           rendered_content, user_id, recipient_id)
             zerver_message.append(zulip_message)
 

zerver/data_import/hipchat.py

@@ -594,9 +594,9 @@ def process_raw_message_batch(realm_id: int,
         rendered_content = None
 
         if is_pm_data:
-            subject = ''
+            topic_name = ''
         else:
-            subject = 'imported from hipchat'
+            topic_name = 'imported from hipchat'
         user_id = raw_message['sender_id']
 
         # Another side effect:
@@ -620,7 +620,7 @@ def process_raw_message_batch(realm_id: int,
             pub_date=pub_date,
             recipient_id=recipient_id,
             rendered_content=rendered_content,
-            subject=subject,
+            topic_name=topic_name,
             user_id=user_id,
             has_attachment=has_attachment,
         )

zerver/data_import/import_util.py

@@ -326,13 +326,12 @@ def build_stream(date_created: Any, realm_id: int, name: str,
     stream_dict['realm'] = realm_id
     return stream_dict
 
-def build_message(subject: str, pub_date: float, message_id: int, content: str,
+def build_message(topic_name: str, pub_date: float, message_id: int, content: str,
                   rendered_content: Optional[str], user_id: int, recipient_id: int,
                   has_image: bool=False, has_link: bool=False,
                   has_attachment: bool=True) -> ZerverFieldsT:
     zulip_message = Message(
         rendered_content_version=1,  # this is Zulip specific
-        subject=subject,
         pub_date=pub_date,
         id=message_id,
         content=content,
@@ -340,6 +339,7 @@ def build_message(subject: str, pub_date: float, message_id: int, content: str,
         has_image=has_image,
         has_attachment=has_attachment,
         has_link=has_link)
+    zulip_message.set_topic_name(topic_name)
     zulip_message_dict = model_to_dict(zulip_message,
                                        exclude=['recipient', 'sender', 'sending_client'])
     zulip_message_dict['sender'] = user_id

zerver/data_import/slack.py

@@ -612,9 +612,9 @@ def channel_message_to_zerver_message(realm_id: int,
         has_image = file_info['has_image']
 
         # construct message
-        subject = 'imported from slack'
+        topic_name = 'imported from slack'
 
-        zulip_message = build_message(subject, float(message['ts']), message_id, content,
+        zulip_message = build_message(topic_name, float(message['ts']), message_id, content,
                                       rendered_content, added_users[user], recipient_id,
                                       has_image, has_link, has_attachment)
         zerver_message.append(zulip_message)

zerver/lib/topic.py

@@ -32,6 +32,10 @@ MATCH_TOPIC = "match_subject"
 # unless we do a pretty tricky migration.
 LEGACY_PREV_TOPIC = "prev_subject"
 
+# This constant is pretty closely coupled to the
+# database, but it's the JSON field.
+EXPORT_TOPIC_NAME = "subject"
+
 # This is used in low-level message functions in
 # zerver/lib/message.py, and it's not user facing.
 DB_TOPIC_NAME = "subject"

zerver/tests/test_slack_importer.py

@@ -40,6 +40,9 @@ from zerver.lib.avatar_hash import (
 from zerver.lib.test_classes import (
     ZulipTestCase,
 )
+from zerver.lib.topic import (
+    EXPORT_TOPIC_NAME,
+)
 from zerver.models import (
     Realm,
     get_realm,
@@ -465,10 +468,10 @@ class SlackImporter(ZulipTestCase):
         self.assertEqual(zerver_message[2]['content'], 'http://journals.plos.org/plosone/article')
         self.assertEqual(zerver_message[2]['has_link'], True)
 
-        self.assertEqual(zerver_message[3]['subject'], 'imported from slack')
+        self.assertEqual(zerver_message[3][EXPORT_TOPIC_NAME], 'imported from slack')
         self.assertEqual(zerver_message[3]['content'], '/me added bot')
         self.assertEqual(zerver_message[4]['recipient'], added_recipient['general'])
-        self.assertEqual(zerver_message[2]['subject'], 'imported from slack')
+        self.assertEqual(zerver_message[2][EXPORT_TOPIC_NAME], 'imported from slack')
         self.assertEqual(zerver_message[1]['recipient'], added_recipient['random'])
 
         self.assertEqual(zerver_message[3]['id'], zerver_message[0]['id'] + 3)