Make the test suite even faster with available apps

[Aymeric Augustin]

There's a few TestCases that run call_command('syncdb', ...). They would be much faster with a suitable value of available_apps.

As usual the idea is from Anssi: ​https://github.com/akaariai/django/commit/b101db2d5f738535aef18db73db2a156666346e3

[Aymeric Augustin]

The following hack helps locate culprits:

diff --git a/django/core/management/sql.py b/django/core/management/sql.py
index b58d89f..eeeb483 100644
--- a/django/core/management/sql.py
+++ b/django/core/management/sql.py
@@ -207,6 +207,8 @@ def emit_pre_sync_signal(create_models, verbosity, interactive, db):
 
 def emit_post_sync_signal(created_models, verbosity, interactive, db):
     # Emit the post_sync signal for every application.
+    print("post-syncdb on %d apps" % len(models.get_apps()))
+    import pdb; pdb.set_trace()
     for app in models.get_apps():
         app_name = app.__name__.split('.')[-2]
         if verbosity >= 2:

[Aymeric Augustin <aymeric.augustin@…>]

In c3df86661955f218de4788a57338bb23428f5525:

Fixed #20603 -- Made the test suite faster.

By avoiding to run syncdb with the full set of test models.

Thanks Anssi for the idea.