diff options
Diffstat (limited to 'django/core/management/validation.py')
| -rw-r--r-- | django/core/management/validation.py | 45 |
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() |