From d4bfb712d2107cbe567fd27f3da860b930adcd4f Mon Sep 17 00:00:00 2001
From: Joris van Rantwijk <joris@jorisvr.nl>
Date: Mon, 6 Feb 2023 13:58:38 +0100
Subject: [PATCH] Add a few tests for maximum cardinality

---
 python/test_matching.py | 45 ++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 44 insertions(+), 1 deletion(-)

diff --git a/python/test_matching.py b/python/test_matching.py
index 4195d60..059ecaf 100644
--- a/python/test_matching.py
+++ b/python/test_matching.py
@@ -2,10 +2,13 @@
 
 import unittest
 
-from max_weight_matching import maximum_weight_matching as mwm
+from max_weight_matching import (
+    maximum_weight_matching as mwm,
+    adjust_weights_for_maximum_cardinality_matching as adj)
 
 
 class TestMaximumWeightMatching(unittest.TestCase):
+    """Test maximum_weight_matching() function."""
 
     def test10_empty(self):
         """empty input graph"""
@@ -126,6 +129,46 @@ class TestMaximumWeightMatching(unittest.TestCase):
             [(1,2), (3,5), (7,6), (8,10), (4,9)])
 
 
+class TestAdjustWeightForMaxCardinality(unittest.TestCase):
+    """Test adjust_weights_for_maximum_cardinality_matching() function."""
+
+    def test_chain(self):
+        self.assertEqual(
+            adj([(0,1,2), (1,2,8), (2,3,3), (3,4,9), (4,5,1), (5,6,7), (6,7,4)]),
+            [(0,1,65), (1,2,71), (2,3,66), (3,4,72), (4,5,64), (5,6,70), (6,7,67)])
+
+    def test_chain_preadjusted(self):
+        self.assertEqual(
+            adj([(0,1,65), (1,2,71), (2,3,66), (3,4,72), (4,5,64), (5,6,70), (6,7,67)]),
+            [(0,1,65), (1,2,71), (2,3,66), (3,4,72), (4,5,64), (5,6,70), (6,7,67)])
+
+    def test14_maxcard(self):
+        self.assertEqual(
+            adj([(1,2,5), (2,3,11), (3,4,5)]),
+            [(1,2,30), (2,3,36), (3,4,30)])
+
+    def test16_negative(self):
+        self.assertEqual(
+            adj([(1,2,2), (1,3,-2), (2,3,1), (2,4,-1), (3,4,-6)]),
+            [(1,2,48), (1,3,44), (2,3,47), (2,4,45), (3,4,40)])
+
+
+class TestMaximumCardinalityMatching(unittest.TestCase):
+    """Test maximum cardinality matching."""
+
+    def test14_maxcard(self):
+        """maximum cardinality"""
+        self.assertEqual(
+            mwm(adj([(1,2,5), (2,3,11), (3,4,5)])),
+            [(1,2), (3,4)])
+
+    def test16_negative(self):
+        """negative weights"""
+        self.assertEqual(
+            mwm(adj([(1,2,2), (1,3,-2), (2,3,1), (2,4,-1), (3,4,-6)])),
+            [(1,3), (2,4)])
+
+
 if __name__ == "__main__":
     unittest.main()