Fixed #10348: ChangeList no longer overwrites a select_related provided by `ModelAdmin.queryset()`.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@10782 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/contrib/admin/views/main.py

@@ -197,19 +197,21 @@ class ChangeList(object):
             raise IncorrectLookupParameters
 
         # Use select_related() if one of the list_display options is a field
-        # with a relationship.
-        if self.list_select_related:
-            qs = qs.select_related()
-        else:
-            for field_name in self.list_display:
-                try:
-                    f = self.lookup_opts.get_field(field_name)
-                except models.FieldDoesNotExist:
-                    pass
-                else:
-                    if isinstance(f.rel, models.ManyToOneRel):
-                        qs = qs.select_related()
-                        break
+        # with a relationship and the provided queryset doesn't already have
+        # select_related defined.
+        if not qs.query.select_related:
+            if self.list_select_related:
+                qs = qs.select_related()
+            else:
+                for field_name in self.list_display:
+                    try:
+                        f = self.lookup_opts.get_field(field_name)
+                    except models.FieldDoesNotExist:
+                        pass
+                    else:
+                        if isinstance(f.rel, models.ManyToOneRel):
+                            qs = qs.select_related()
+                            break
 
         # Set ordering.
         if self.order_field:

tests/regressiontests/admin_changelist/models.py

+from django.db import models
+from django.contrib import admin
+
+class Parent(models.Model):
+    name = models.CharField(max_length=128)
+
+class Child(models.Model):
+    parent = models.ForeignKey(Parent, editable=False)
+    name = models.CharField(max_length=30, blank=True)
\ No newline at end of file

tests/regressiontests/admin_changelist/tests.py

+import unittest 
+from django.contrib import admin
+from django.contrib.admin.views.main import ChangeList
+from regressiontests.admin_changelist.models import Child
+
+class ChangeListTests(unittest.TestCase):
+    def test_select_related_preserved(self):
+        """
+        Regression test for #10348: ChangeList.get_query_set() shouldn't
+        overwrite a custom select_related provided by ModelAdmin.queryset().
+        """
+        m = ChildAdmin(Child, admin.site)
+        cl = ChangeList(MockRequest(), Child, m.list_display, m.list_display_links, 
+                m.list_filter,m.date_hierarchy, m.search_fields, 
+                m.list_select_related, m.list_per_page, m.list_editable, m)
+        self.assertEqual(cl.query_set.query.select_related, {'parent': {'name': {}}})
+
+class ChildAdmin(admin.ModelAdmin):
+    list_display = ['name', 'parent']
+    def queryset(self, request):
+        return super(ChildAdmin, self).queryset(request).select_related("parent__name")
+
+class MockRequest(object):
+    GET = {}