From ad3f7e7b5d81b1384189f7be821ce5530cd2f16d Mon Sep 17 00:00:00 2001
From: dualfroz <me@dualfroz.com>
Date: Fri, 4 Sep 2026 09:39:40 +0200
Subject: [PATCH] fix: make Delorean hashable by defining __hash__

Defining __eq__ without __hash__ sets __hash__ to None in Python 3, so
Delorean instances were unhashable and could not be used in sets or as
dict keys (unlike datetime). Hash on self.epoch, the same value __eq__
compares, so equal instances hash equal.
---
 delorean/dates.py       |  4 ++++
 tests/delorean_tests.py | 14 ++++++++++++++
 2 files changed, 18 insertions(+)

diff --git a/delorean/dates.py b/delorean/dates.py
index 4dc00ba..fac318d 100644
--- a/delorean/dates.py
+++ b/delorean/dates.py
@@ -240,6 +240,10 @@ class Delorean(object):
             return self.epoch == other.epoch
         return False
 
+    def __hash__(self):
+        # Hash on what __eq__ compares, so equal instants hash equal.
+        return hash(self.epoch)
+
     def __lt__(self, other):
         return self.epoch < other.epoch
 
diff --git a/tests/delorean_tests.py b/tests/delorean_tests.py
index 5ab5061..5bdfa6f 100644
--- a/tests/delorean_tests.py
+++ b/tests/delorean_tests.py
@@ -50,6 +50,20 @@ class DeloreanTests(unittest.TestCase):
         dt = date(2013, 5, 6)
         self.assertRaises(ValueError, delorean.Delorean, dt)
 
+    def test_hashable(self):
+        # Defining __eq__ without __hash__ makes instances unhashable in Python 3.
+        self.assertEqual(hash(self.do), hash(self.do))
+        self.assertIn(self.do, {self.do})
+        mapping = {self.do: "value"}
+        self.assertEqual(mapping[self.do], "value")
+
+    def test_hash_consistent_with_equality(self):
+        # Equal objects (same instant, different timezone) must hash equal.
+        other = self.do.shift("US/Pacific")
+        self.assertEqual(self.do, other)
+        self.assertEqual(hash(self.do), hash(other))
+        self.assertEqual(len({self.do, other}), 1)
+
     def test_initialize_from_datetime_naive(self):
         self.assertRaises(
             delorean.DeloreanInvalidTimezone, delorean.Delorean, datetime=self.naive_dt