From 3780c31c5901e3da087f8d6b38fbe5790f24dc96 2020-05-28 13:01:00
From: Brett Smith <brettcsmith@brettcsmith.org>
Date: 2020-05-28 13:01:00
Subject: [PATCH] reports: Add Balance.__eq__() method.

It turns out the provided implementation gets us most of the way there,
we just needed to add handling for the special case of zero balances.
Now it's confirmed with tests.

---

diff --git a/conservancy_beancount/reports/core.py b/conservancy_beancount/reports/core.py
index 5ded97fbd1b84a474817f64c0fa1469ea21543a1..e2f474ed1332c948d985b6dd3be77cc010b6da57 100644
--- a/conservancy_beancount/reports/core.py
+++ b/conservancy_beancount/reports/core.py
@@ -71,6 +71,14 @@ class Balance(Mapping[str, data.Amount]):
         amounts.sort(key=lambda amt: abs(amt.number), reverse=True)
         return ', '.join(str(amount) for amount in amounts)
 
+    def __eq__(self, other: Any) -> bool:
+        if (self.is_zero()
+            and isinstance(other, Balance)
+            and other.is_zero()):
+            return True
+        else:
+            return super().__eq__(other)
+
     def __neg__(self) -> 'Balance':
         return type(self)(
             (key, -amt) for key, amt in self.items()
diff --git a/tests/test_reports_balance.py b/tests/test_reports_balance.py
index 249a288d9890209e8265085d419725db5e8f130c..07e238662870c712fc76a39a84f210ac8aa691c1 100644
--- a/tests/test_reports_balance.py
+++ b/tests/test_reports_balance.py
@@ -133,6 +133,23 @@ def test_neg(balance_map_kwargs):
     for key in balance_map_kwargs:
         assert actual[key] == -amounts[key]
 
+@pytest.mark.parametrize('kwargs1,kwargs2,expected', [
+    ({}, {}, True),
+    ({}, {'USD': 0}, True),
+    ({}, {'EUR': 1}, False),
+    ({'USD': 1}, {'EUR': 1}, False),
+    ({'USD': 1}, {'USD': '1.0'}, True),
+    ({'USD': 1}, {'USD': '1.0', 'EUR': '2.0'}, False),
+    ({'USD': 1, 'BRL': '2.0'}, {'USD': '1.0', 'EUR': '2.0'}, False),
+    ({'USD': 1, 'EUR': 2, 'BRL': '3.0'}, {'USD': '1.0', 'EUR': '2.0'}, False),
+    ({'USD': 1, 'EUR': 2}, {'USD': '1.0', 'EUR': '2.0'}, True),
+])
+def test_eq(kwargs1, kwargs2, expected):
+    bal1 = core.Balance(testutil.balance_map(**kwargs1))
+    bal2 = core.Balance(testutil.balance_map(**kwargs2))
+    actual = bal1 == bal2
+    assert actual == expected
+
 @pytest.mark.parametrize('balance_map_kwargs,expected', [
     ({}, "Zero balance"),
     ({'JPY': 0, 'BRL': 0}, "Zero balance"),