From da8d29d02492fbb1ea39f67dcccc90175447282c Mon Sep 17 00:00:00 2001
From: weidongkl <weidongkl@sina.com>
Date: Mon, 13 Nov 2023 13:54:20 +0800
Subject: [PATCH] fix: error in determining timestamp less than

```
__lt__ is the negation of __gt__ by default.
so samples.Timestamp(1, 1) > samples.Timestamp(1, 1) is false
and samples.Timestamp(1, 1) < samples.Timestamp(1, 1) is true.
but  samples.Timestamp(1, 1) < samples.Timestamp(1, 1) should be false too.
add __lt__ func to fix the bug
```

Signed-off-by: weidongkl <weidongkl@sina.com>
---
 prometheus_client/samples.py |  3 +++
 tests/test_samples.py        | 27 +++++++++++++++++++++++++++
 2 files changed, 30 insertions(+)
 create mode 100644 tests/test_samples.py

diff --git a/prometheus_client/samples.py b/prometheus_client/samples.py
index d3e351c6..8735fed9 100644
--- a/prometheus_client/samples.py
+++ b/prometheus_client/samples.py
@@ -30,6 +30,9 @@ def __ne__(self, other: object) -> bool:
     def __gt__(self, other: "Timestamp") -> bool:
         return self.sec > other.sec or self.nsec > other.nsec
 
+    def __lt__(self, other: "Timestamp") -> bool:
+        return self.sec < other.sec or self.nsec < other.nsec
+
 
 # Timestamp and exemplar are optional.
 # Value can be an int or a float.
diff --git a/tests/test_samples.py b/tests/test_samples.py
new file mode 100644
index 00000000..796afe7e
--- /dev/null
+++ b/tests/test_samples.py
@@ -0,0 +1,27 @@
+import unittest
+
+from prometheus_client import samples
+
+
+class TestSamples(unittest.TestCase):
+    def test_gt(self):
+        self.assertEqual(samples.Timestamp(1, 1) > samples.Timestamp(1, 1), False)
+        self.assertEqual(samples.Timestamp(1, 1) > samples.Timestamp(1, 2), False)
+        self.assertEqual(samples.Timestamp(1, 1) > samples.Timestamp(2, 1), False)
+        self.assertEqual(samples.Timestamp(1, 1) > samples.Timestamp(2, 2), False)
+        self.assertEqual(samples.Timestamp(1, 2) > samples.Timestamp(1, 1), True)
+        self.assertEqual(samples.Timestamp(2, 1) > samples.Timestamp(1, 1), True)
+        self.assertEqual(samples.Timestamp(2, 2) > samples.Timestamp(1, 1), True)
+
+    def test_lt(self):
+        self.assertEqual(samples.Timestamp(1, 1) < samples.Timestamp(1, 1), False)
+        self.assertEqual(samples.Timestamp(1, 1) < samples.Timestamp(1, 2), True)
+        self.assertEqual(samples.Timestamp(1, 1) < samples.Timestamp(2, 1), True)
+        self.assertEqual(samples.Timestamp(1, 1) < samples.Timestamp(2, 2), True)
+        self.assertEqual(samples.Timestamp(1, 2) < samples.Timestamp(1, 1), False)
+        self.assertEqual(samples.Timestamp(2, 1) < samples.Timestamp(1, 1), False)
+        self.assertEqual(samples.Timestamp(2, 2) < samples.Timestamp(1, 1), False)
+
+
+if __name__ == '__main__':
+    unittest.main()