1 files changed, 54 insertions, 0 deletions
diff --git a/tests/schema/fields.py b/tests/schema/fields.py
new file mode 100644
index 0000000000..596671a6bc
--- /dev/null
+++ b/tests/schema/fields.py
@@ -0,0 +1,54 @@
+from django.db.models.fields.related import (
+    create_many_to_many_intermediary_model,
+    ManyToManyField, ManyToManyRel, RelatedField,
+    RECURSIVE_RELATIONSHIP_CONSTANT, ReverseManyRelatedObjectsDescriptor,
+)
+from django.utils.functional import curry
+
+
+class CustomManyToManyField(RelatedField):
+    """
+    Ticket #24104 - Need to have a custom ManyToManyField,
+    which is not an inheritor of ManyToManyField.
+    """
+
+    def __init__(self, to, db_constraint=True, swappable=True, **kwargs):
+        try:
+            to._meta
+        except AttributeError:
+            to = str(to)
+        kwargs['verbose_name'] = kwargs.get('verbose_name', None)
+        kwargs['rel'] = ManyToManyRel(
+            to,
+            related_name=kwargs.pop('related_name', None),
+            related_query_name=kwargs.pop('related_query_name', None),
+            limit_choices_to=kwargs.pop('limit_choices_to', None),
+            symmetrical=kwargs.pop('symmetrical', to == RECURSIVE_RELATIONSHIP_CONSTANT),
+            through=kwargs.pop('through', None),
+            through_fields=kwargs.pop('through_fields', None),
+            db_constraint=db_constraint,
+        )
+        self.swappable = swappable
+        self.db_table = kwargs.pop('db_table', None)
+        if kwargs['rel'].through is not None:
+            assert self.db_table is None, "Cannot specify a db_table if an intermediary model is used."
+        super(CustomManyToManyField, self).__init__(**kwargs)
+
+    def contribute_to_class(self, cls, name):
+        if self.rel.symmetrical and (self.rel.to == "self" or self.rel.to == cls._meta.object_name):
+            self.rel.related_name = "%s_rel_+" % name
+        super(CustomManyToManyField, self).contribute_to_class(cls, name)
+        if not self.rel.through and not cls._meta.abstract and not cls._meta.swapped:
+            self.rel.through = create_many_to_many_intermediary_model(self, cls)
+        setattr(cls, self.name, ReverseManyRelatedObjectsDescriptor(self))
+        self.m2m_db_table = curry(self._get_m2m_db_table, cls._meta)
+
+    def get_internal_type(self):
+        return 'ManyToManyField'
+
+    # Copy those methods from ManyToManyField because they don't call super() internally
+    contribute_to_related_class = ManyToManyField.__dict__['contribute_to_related_class']
+    set_attributes_from_rel = ManyToManyField.__dict__['set_attributes_from_rel']
+    _get_m2m_attr = ManyToManyField.__dict__['_get_m2m_attr']
+    _get_m2m_reverse_attr = ManyToManyField.__dict__['_get_m2m_reverse_attr']
+    _get_m2m_db_table = ManyToManyField.__dict__['_get_m2m_db_table']