Ticket #7042: t7042_r8472_patch.diff

django/core/management/validation.py

@@ -110 +110 @@
                 # so skip the next section
                 if isinstance(f.rel.to, (str, unicode)):
                     continue
+            
+            # Check that the field is not set to unique.  ManyToManyFields do not support unique.
+            if f.unique:
+                e.add(opts, "ManyToManyFields cannot be unique.  Remove the unique argument on '%s'." % f.name)
+            
             if getattr(f.rel, 'through', None) is not None:
                 if hasattr(f.rel, 'through_model'):
                     from_model, to_model = cls, f.rel.to

tests/modeltests/invalid_models/models.py

@@ -177 +177 @@
     fk1 = models.ForeignKey('AbstractModel')
     fk2 = models.ManyToManyField('AbstractModel')
     
+class UniqueM2M(models.Model):
+    """ Model to test for unique ManyToManyFields, which are invalid. """
+    unique_people = models.ManyToManyField( Person, unique=True )
+    
 model_errors = """invalid_models.fielderrors: "charfield": CharFields require a "max_length" attribute.
 invalid_models.fielderrors: "decimalfield": DecimalFields require a "decimal_places" attribute.
 invalid_models.fielderrors: "decimalfield": DecimalFields require a "max_digits" attribute.
@@ -271 +275 @@
 invalid_models.personselfrefm2mexplicit: Many-to-many fields with intermediate tables cannot be symmetrical.
 invalid_models.abstractrelationmodel: 'fk1' has a relation with model AbstractModel, which has either not been installed or is abstract.
 invalid_models.abstractrelationmodel: 'fk2' has an m2m relation with model AbstractModel, which has either not been installed or is abstract.
+invalid_models.uniquem2m: ManyToManyFields cannot be unique.  Remove the unique argument on 'unique_people'.
 """