Add coin leaderboard command

tests/test_release_063.py

@@ -246,6 +246,22 @@ class Release063GameTests(unittest.TestCase):
         self.assertIn("贷款金额必须为 1～500", self.command("/loan 501"))
         self.assertIn("当前没有未还贷款", self.command("/还款 全部"))
 
+    def test_coin_ranking_lists_accounts_by_balance(self):
+        self.assertIn("金币 1000", self.command("/金币"))
+        self.assertIn("金币 1000", self.command("/金币", sender="Bob"))
+        self.assertIn("金币 1000", self.command("/金币", sender="Carol"))
+        self.command("/转账 Bob 250")
+        self.command("/贷款 100", sender="Carol")
+
+        ranking = self.command("/大富翁榜")
+
+        self.assertIn("大富翁榜：", ranking)
+        self.assertIn("1. bob 1250 金币", ranking)
+        self.assertIn("2. carol 1100 金币（未还贷款 100）", ranking)
+        self.assertIn("3. alice 750 金币", ranking)
+        self.assertNotIn("Dave", ranking)
+        self.assertIn("金币排行人数必须为 1～20", self.command("/金币排行 0"))
+
     def test_open_round_and_history_survive_restart(self):
         root = Path(self.temp.name)
         self.command("/彩票开始")