[2.0.x] Fixed #28629 -- Made tree.Node instances hashable.

Regression in 508b5debfb16843a8443ebac82c1fb91f15da687 which
added Node.__eq__().

Backport of fc6528b25ab1834be1a478b405bf8f7ec5cf860c from master

2 files changed, 13 insertions, 0 deletions

diff --git a/django/utils/tree.py b/django/utils/tree.py
index 74612736f1..677f03d1b2 100644
--- a/django/utils/tree.py
+++ b/django/utils/tree.py
@@ -70,6 +70,9 @@ class Node:
             return self.children == other.children
         return False
 
+    def __hash__(self):
+        return hash((self.__class__, self.connector, self.negated) + tuple(self.children))
+
     def add(self, data, conn_type, squash=True):
         """
         Combine this tree and the data represented by data using the
diff --git a/tests/utils_tests/test_tree.py b/tests/utils_tests/test_tree.py
index 98db5f6012..65f49c06a6 100644
--- a/tests/utils_tests/test_tree.py
+++ b/tests/utils_tests/test_tree.py
@@ -19,6 +19,16 @@ class NodeTests(unittest.TestCase):
                          "<Node: (DEFAULT: ('a', 1), ('b', 2))>")
         self.assertEqual(repr(self.node2), "<Node: (DEFAULT: )>")
 
+    def test_hash(self):
+        node3 = Node(self.node1_children, negated=True)
+        node4 = Node(self.node1_children, connector='OTHER')
+        node5 = Node(self.node1_children)
+        self.assertNotEqual(hash(self.node1), hash(self.node2))
+        self.assertNotEqual(hash(self.node1), hash(node3))
+        self.assertNotEqual(hash(self.node1), hash(node4))
+        self.assertEqual(hash(self.node1), hash(node5))
+        self.assertEqual(hash(self.node2), hash(Node()))
+
     def test_len(self):
         self.assertEqual(len(self.node1), 2)
         self.assertEqual(len(self.node2), 0)