Fix #698

Author: dimitri-yatsenko

datajoint/table.py

@@ -45,14 +45,9 @@ def heading(self):
         """
         if self._heading is None:
             self._heading = Heading()  # instance-level heading
-        if not self._heading:  # lazy loading of heading
-            if self.connection is None:
-                raise DataJointError(
-                    'DataJoint class is missing a database connection. '
-                    'Missing schema decorator on the class? (e.g. @schema)')
-            else:
-                self._heading.init_from_database(
-                    self.connection, self.database, self.table_name, self.declaration_context)
+        if not self._heading and self.connection is not None:  # lazy loading of heading
+            self._heading.init_from_database(
+                self.connection, self.database, self.table_name, self.declaration_context)
         return self._heading
 
     def declare(self, context=None):

datajoint/user_tables.py

@@ -13,7 +13,7 @@
 # attributes that trigger instantiation of user classes
 supported_class_attrs = {
     'key_source', 'describe', 'alter', 'heading', 'populate', 'progress', 'primary_key', 'proj', 'aggr',
-    'fetch', 'fetch1','head', 'tail',
+    'fetch', 'fetch1', 'head', 'tail',
     'insert', 'insert1', 'drop', 'drop_quick', 'delete', 'delete_quick'}
 
 
@@ -92,7 +92,7 @@ def table_name(cls):
 
     @ClassProperty
     def full_table_name(cls):
-        if cls not in {Manual, Imported, Lookup, Computed, Part}:
+        if cls not in {Manual, Imported, Lookup, Computed, Part, UserTable}:
             if cls.database is None:
                 raise DataJointError('Class %s is not properly declared (schema decorator not applied?)' % cls.__name__)
             return r"`{0:s}`.`{1:s}`".format(cls.database, cls.table_name)

tests/schema.py

@@ -13,6 +13,9 @@
 
 @schema
 class TTest(dj.Lookup):
+    """
+    doc string
+    """
     definition = """
     key   :   int     # key
     ---

tests/test_relation.py

@@ -36,6 +36,12 @@ def setup_class(cls):
         cls.img = schema.Image()
         cls.trash = schema.UberTrash()
 
+    def test_class_help(self):
+        help(schema.TTest)
+
+    def test_instance_help(self):
+        help(schema.TTest())
+
     def test_contents(self):
         """
         test the ability of tables to self-populate using the contents property