# HG changeset patch -- Bitbucket.org
# Project south
# URL https://bitbucket.org/andrewgodwin/south/overview
# User John Paulett <john@paulett.org>
# Date 1300138995 18000
# Node ID 21a63523132712eead38df6f3e43f7e616c114be
# Parent  5bc35f14338fa86e051702943365942715a6a2ab
Avoid flushing the database during create_test_db to preserve data migrations.

Django 1.3-rc-1 introduced a backwards incompatible change (#14661) that runs flush
after syncdb during testing, thus clearing out all South data migrations.

This fix no-ops the flush command during create_test_db, but allows flush in
test teardowns.

--- a/south/management/commands/__init__.py
+++ b/south/management/commands/__init__.py
@@ -9,6 +9,7 @@ from django.conf import settings
 # Make sure the template loader cache is fixed _now_ (#448)
 import django.template.loaders.app_directories
 
+from south.hacks import hacks
 from south.management.commands.syncdb import Command as SyncCommand
 
 class MigrateAndSyncCommand(SyncCommand):
@@ -31,3 +32,9 @@ def patch_for_test_db_setup():
         management._commands['syncdb'] = 'django.core'
     else:
         management._commands['syncdb'] = MigrateAndSyncCommand()
+        # Avoid flushing data migrations.
+        # http://code.djangoproject.com/ticket/14661 introduced change that flushed custom
+        # sql during the test database creation (thus flushing the data migrations).
+        # we patch flush to be no-op during create_test_db, but still allow flushing
+        # after each test for non-transactional backends.
+        hacks.patch_flush_during_test_db_creation()

--- a/south/hacks/django_1_0.py
+++ b/south/hacks/django_1_0.py
@@ -4,9 +4,17 @@ Hacks for the Django 1.0/1.0.2 releases.
 
 from django.conf import settings
 from django.db import models
+from django.db.backends.creation import BaseDatabaseCreation
 from django.db.models.loading import AppCache, cache
+from django.core import management
+from django.core.management.commands.flush import Command as FlushCommand
 from django.utils.datastructures import SortedDict
 
+class SkipFlushCommand(FlushCommand):
+    def handle_noargs(self, **options):
+        # no-op to avoid calling flush
+        return
+
 class Hacks:
     
     def set_installed_apps(self, apps):
@@ -72,4 +80,24 @@ class Hacks:
         Rebuilds AppCache with the real model definitions.
         """
         cache._populate()
-    
+
+    def patch_flush_during_test_db_creation(self):
+        """
+        Patches BaseDatabaseCreation.create_test_db to not flush database
+        """
+
+        def patch(f):
+            def wrapper(*args, **kwargs):
+                # hold onto the original and replace flush command with a no-op
+                original_flush_command = management._commands['flush']
+                try:
+                    management._commands['flush'] = SkipFlushCommand()
+                    # run create_test_db
+                    f(*args, **kwargs)
+                finally:
+                    # unpatch flush back to the original
+                    management._commands['flush'] = original_flush_command
+            return wrapper
+            
+        BaseDatabaseCreation.create_test_db = patch(BaseDatabaseCreation.create_test_db)
+