From d43aa28f67c52bc6f5ea5868c711df263895713f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Anssi=20K=C3=A4=C3=A4ri=C3=A4inen?=
 <anssi.kaariainen@thl.fi>
Date: Thu, 26 Feb 2015 15:44:41 +0200
Subject: [PATCH] Removed field.field check in setup_joins()

---
 django/db/models/fields/related.py | 10 ++++++++++
 django/db/models/sql/compiler.py   |  2 +-
 django/db/models/sql/query.py      | 14 +++-----------
 3 files changed, 14 insertions(+), 12 deletions(-)

diff --git a/django/db/models/fields/related.py b/django/db/models/fields/related.py
index e91de27876..2a5a374065 100644
--- a/django/db/models/fields/related.py
+++ b/django/db/models/fields/related.py
@@ -1342,6 +1342,16 @@ class ForeignObjectRel(object):
     def get_prep_lookup(self, lookup_name, value):
         return self.field.get_prep_lookup(lookup_name, value)
 
+    @cached_property
+    def target_field(self):
+        target_fields = self.get_path_info().target_fields
+        if len(target_fields) > 1:
+            raise RuntimeError("Multicolumn relations do not have a single target_field.")
+        return target_fields[0]
+
+    def get_lookup(self, lookup_name):
+        return self.field.get_lookup(lookup_name)
+
     def get_internal_type(self):
         return self.field.get_internal_type()
 
diff --git a/django/db/models/sql/compiler.py b/django/db/models/sql/compiler.py
index 97022d554a..d54c1bc5e4 100644
--- a/django/db/models/sql/compiler.py
+++ b/django/db/models/sql/compiler.py
@@ -547,7 +547,7 @@ class SQLCompiler(object):
         # If we get to this point and the field is a relation to another model,
         # append the default ordering for that model unless the attribute name
         # of the field is specified.
-        if field.rel and path and opts.ordering and name != field.attname:
+        if field.is_relation and path and opts.ordering and name != field.attname:
             # Firstly, avoid infinite loops.
             if not already_seen:
                 already_seen = set()
diff --git a/django/db/models/sql/query.py b/django/db/models/sql/query.py
index 9c19e819fd..c041ef0b07 100644
--- a/django/db/models/sql/query.py
+++ b/django/db/models/sql/query.py
@@ -1038,7 +1038,7 @@ class Query(object):
         """
         Checks the type of object passed to query relations.
         """
-        if field.rel:
+        if field.is_relation:
             # QuerySets implement is_compatible_query_object_type() to
             # determine compatibility with the given field.
             if hasattr(value, 'is_compatible_query_object_type'):
@@ -1164,16 +1164,10 @@ class Query(object):
             # No support for transforms for relational fields
             assert len(lookups) == 1
             lookup_class = field.get_lookup(lookups[0])
-            # Undo the changes done in setup_joins() if hasattr(final_field, 'field') branch
-            # This hack is needed as long as the field.rel isn't like a real field.
-            if field.get_path_info()[-1].target_fields != sources:
-                target_field = field.rel
-            else:
-                target_field = field
             if len(targets) == 1:
-                lhs = targets[0].get_col(alias, target_field)
+                lhs = targets[0].get_col(alias, field)
             else:
-                lhs = MultiColSource(alias, targets, sources, target_field)
+                lhs = MultiColSource(alias, targets, sources, field)
             condition = lookup_class(lhs, value)
             lookup_type = lookup_class.lookup_name
         else:
@@ -1384,8 +1378,6 @@ class Query(object):
             reuse = can_reuse if join.m2m else None
             alias = self.join(connection, reuse=reuse)
             joins.append(alias)
-        if hasattr(final_field, 'field'):
-            final_field = final_field.field
         return final_field, targets, opts, joins, path
 
     def trim_joins(self, targets, joins, path):