feat: big

cost/tests/test_services.py

@@ -171,6 +171,33 @@ class CreateCostEntryTests(TestCase):
         self.assertEqual(entry.source_id, '')
         self.assertEqual(entry.remarks, '')
 
+    def test_create_cost_entry_with_formula_fields(self):
+        """传入 unit_amount + quantity 时自动计算最终 amount"""
+        entry = cost_services.create_cost_entry(
+            merchant=self.merchant,
+            category=self.category,
+            unit_amount=Decimal('180.00'),
+            quantity=Decimal('2'),
+            unit_name='人天',
+            occurred_at=date(2026, 6, 4),
+        )
+        self.assertEqual(entry.amount, Decimal('360.00'))
+        self.assertEqual(entry.unit_amount, Decimal('180.0000'))
+        self.assertEqual(entry.quantity, Decimal('2.0000'))
+        self.assertEqual(entry.unit_name, '人天')
+
+    def test_create_cost_entry_formula_overrides_amount(self):
+        """倍数型支出以公式结果作为最终统计金额"""
+        entry = cost_services.create_cost_entry(
+            merchant=self.merchant,
+            category=self.category,
+            amount=Decimal('999.00'),
+            unit_amount=Decimal('120.00'),
+            quantity=Decimal('3'),
+            occurred_at=date(2026, 6, 4),
+        )
+        self.assertEqual(entry.amount, Decimal('360.00'))
+
 
 class MockCostProvider:
     """测试用 Provider"""
@@ -222,6 +249,33 @@ class CollectFromProviderTests(TestCase):
         self.assertEqual(cost_models.CostEntry.objects.count(), 2)
         self.assertEqual(cost_models.CostCategory.objects.count(), 2)
 
+
+    def test_collect_creates_formula_entries(self):
+        """Provider 可以提供 unit_amount + quantity，由 cost 模块计算 amount"""
+        entries = [
+            CostEntryInput(
+                category_key='temp_worker', category_name='临时工工资',
+                amount=None, unit_amount=Decimal('200.00'), quantity=Decimal('3'),
+                unit_name='人天', occurred_at=date(2026, 6, 3),
+                source_module='test', source_id='T001',
+            ),
+        ]
+        provider = MockCostProvider(entries)
+
+        result = cost_services.collect_from_provider(
+            provider=provider,
+            merchant=self.merchant,
+            start_date=date(2026, 6, 1),
+            end_date=date(2026, 6, 30),
+        )
+
+        self.assertEqual(result['created_count'], 1)
+        entry = cost_models.CostEntry.objects.get()
+        self.assertEqual(entry.amount, Decimal('600.00'))
+        self.assertEqual(entry.unit_amount, Decimal('200.0000'))
+        self.assertEqual(entry.quantity, Decimal('3.0000'))
+        self.assertEqual(entry.unit_name, '人天')
+
     def test_collect_returns_not_list_raises(self):
         """Provider 返回非 list 抛 TypeError"""
         class BadProvider: