Ticket #6811: qs_value_expressions.diff

django/db/models/sql/query.py

@@ -1170 +1170 @@
         """
         return not (self.low_mark or self.high_mark)
 
-    def add_fields(self, field_names, allow_m2m=True):
+    def add_fields(self, fields, allow_m2m=True):
         """
         Adds the given (model) fields to the select set. The field names are
         added in the order specified.
         """
         alias = self.get_initial_alias()
         opts = self.get_meta()
+        auto_group = False
+        group_fields = []
         try:
-            for name in field_names:
-                u1, target, u2, joins = self.setup_joins(name.split(LOOKUP_SEP),
-                        opts, alias, False, allow_m2m, True)
-                self.select.append((joins[-1][-1], target.column))
+            for f in fields:
+                if isinstance(f, str):
+                    u1, target, u2, joins = self.setup_joins(f.split(LOOKUP_SEP),
+                            opts, alias, False, allow_m2m, True)
+                    self.select.append((joins[-1][-1], target.column))
+                    group_fields.append((joins[-1][-1], target.column))
+                else:
+                    if hasattr(f, 'get_cols'):
+                        table_map = {}
+                        column_map = {}
+                        for col in f.get_cols():
+                            u1, target, u2, joins = self.setup_joins(col.split(LOOKUP_SEP),
+                                    opts, alias, False, allow_m2m, True)
+                            table_map[''] = joins[-1][-1]
+                            column_map[col] = target.column
+                        f.relabel_aliases(table_map, column_map)
+                    if hasattr(f, 'do_group'):
+                        auto_group = f.do_group()
+                    self.select.append(f)
+            if auto_group:
+                self.group_by.extend(group_fields)
         except JoinError:
-            raise FieldError("Invalid field name: '%s'" % name)
+            raise FieldError("Invalid field name: '%s'" % f)
 
     def add_ordering(self, *ordering):
         """

django/db/models/query.py

@@ -478 +478 @@
 
     def iterator(self):
         self.field_names.extend([f for f in self.query.extra_select.keys()])
+        #field_names = [f if isinstance(f,str) else f.alias() for f in self.field_names]
         for row in self.query.results_iter():
             yield dict(zip(self.field_names, row))
 
@@ -489 +490 @@
         Called by the _clone() method after initialising the rest of the
         instance.
         """
+        # field_names contains strings
+        # fields contains strings or expression objects
         if self._fields:
             if not self.query.extra_select:
-                field_names = list(self._fields)
+                field_names = list(f.output_alias() if hasattr(f,'output_alias') else f for f in self._fields)
+                fields = list(self._fields)
             else:
                 field_names = []
+                fields = []
                 names = set(self.model._meta.get_all_field_names())
                 for f in self._fields:
                     if f in names:
                         field_names.append(f)
+                        fields.append(f)
+                    elif hasattr(f, 'output_alias'):
+                        field_names.append(f.output_alias())
+                        fields.append(f)
                     elif not self.query.extra_select.has_key(f):
                         raise FieldDoesNotExist('%s has no field named %r'
                                 % (self.model._meta.object_name, f))
         else:
             # Default to all fields.
-            field_names = [f.attname for f in self.model._meta.fields]
+            fields = field_names = [f.attname for f in self.model._meta.fields]
 
-        self.query.add_fields(field_names, False)
+        self.query.add_fields(fields)
         self.query.default_cols = False
         self.field_names = field_names