gis: Merged revisions 7981-8001,8003-8011,8013-8033,8035-8036,8038-8039,8041-8063,8065-8076,8078-8139,8141-8154,8156-8214 via svnmerge from trunk.archive/attic/gisattic/gis

git-svn-id: http://code.djangoproject.com/svn/django/branches/gis@8215 bcc190cf-cafb-0310-a4f2-bffc1f526a37

1 files changed, 44 insertions, 1 deletions

diff --git a/django/core/management/validation.py b/django/core/management/validation.py
index e17409ae5d..e9d7b53027 100644
--- a/django/core/management/validation.py
+++ b/django/core/management/validation.py
@@ -102,6 +102,7 @@ def get_validation_errors(outfile, app=None):
                         if r.get_accessor_name() == rel_query_name:
                             e.add(opts, "Reverse query name for field '%s' clashes with related field '%s.%s'. Add a related_name argument to the definition for '%s'." % (f.name, rel_opts.object_name, r.get_accessor_name(), f.name))
 
+        seen_intermediary_signatures = [] 
         for i, f in enumerate(opts.local_many_to_many):
             # Check to see if the related m2m field will clash with any
             # existing fields, m2m fields, m2m related objects or related
@@ -112,7 +113,49 @@ def get_validation_errors(outfile, app=None):
                 # so skip the next section
                 if isinstance(f.rel.to, (str, unicode)):
                     continue
-
+            if getattr(f.rel, 'through', None) is not None:
+                if hasattr(f.rel, 'through_model'):
+                    from_model, to_model = cls, f.rel.to
+                    if from_model == to_model and f.rel.symmetrical:
+                        e.add(opts, "Many-to-many fields with intermediate tables cannot be symmetrical.")
+                    seen_from, seen_to, seen_self = False, False, 0
+                    for inter_field in f.rel.through_model._meta.fields:
+                        rel_to = getattr(inter_field.rel, 'to', None)
+                        if from_model == to_model: # relation to self
+                            if rel_to == from_model:
+                                seen_self += 1
+                            if seen_self > 2:
+                                e.add(opts, "Intermediary model %s has more than two foreign keys to %s, which is ambiguous and is not permitted." % (f.rel.through_model._meta.object_name, from_model._meta.object_name))
+                        else:
+                            if rel_to == from_model:
+                                if seen_from:
+                                    e.add(opts, "Intermediary model %s has more than one foreign key to %s, which is ambiguous and is not permitted." % (f.rel.through_model._meta.object_name, rel_from._meta.object_name))
+                                else:
+                                    seen_from = True
+                            elif rel_to == to_model:
+                                if seen_to:
+                                    e.add(opts, "Intermediary model %s has more than one foreign key to %s, which is ambiguous and is not permitted." % (f.rel.through_model._meta.object_name, rel_to._meta.object_name))
+                                else:
+                                    seen_to = True
+                    if f.rel.through_model not in models.get_models():
+                        e.add(opts, "'%s' specifies an m2m relation through model %s, which has not been installed." % (f.name, f.rel.through))
+                    signature = (f.rel.to, cls, f.rel.through_model)
+                    if signature in seen_intermediary_signatures:
+                        e.add(opts, "The model %s has two manually-defined m2m relations through the model %s, which is not permitted. Please consider using an extra field on your intermediary model instead." % (cls._meta.object_name, f.rel.through_model._meta.object_name))
+                    else:
+                        seen_intermediary_signatures.append(signature)
+                    seen_related_fk, seen_this_fk = False, False
+                    for field in f.rel.through_model._meta.fields:
+                        if field.rel:
+                            if not seen_related_fk and field.rel.to == f.rel.to:
+                                seen_related_fk = True
+                            elif field.rel.to == cls:
+                                seen_this_fk = True
+                    if not seen_related_fk or not seen_this_fk:
+                        e.add(opts, "'%s' has a manually-defined m2m relation through model %s, which does not have foreign keys to %s and %s" % (f.name, f.rel.through, f.rel.to._meta.object_name, cls._meta.object_name))
+                else:
+                    e.add(opts, "'%s' specifies an m2m relation through model %s, which has not been installed" % (f.name, f.rel.through))
+            
             rel_opts = f.rel.to._meta
             rel_name = RelatedObject(f.rel.to, cls, f).get_accessor_name()
             rel_query_name = f.related_query_name()