013 add price multiplier

tests/domain/test_price.py

@@ -80,6 +80,18 @@ def test_filter_valid_prices_handles_empty_input() -> None:
     assert filter_and_sort_prices([]) == []
 
 
+def test_filter_valid_prices_applies_multiplier_and_rounds_half_up() -> None:
+    low = _make_price(provider="cdek", price=Decimal("100.40"))
+    high = _make_price(provider="boxberry", price=Decimal("100.50"))
+
+    result = filter_valid_prices(
+        [low, high],
+        price_multiplier=Decimal("1.1"),
+    )
+
+    assert [price.price for price in result] == [Decimal("110"), Decimal("111")]
+
+
 def test_filter_valid_prices_excludes_invalid_records() -> None:
     valid = _make_price(provider=" cdek ", service_name=" express ", currency="rub")
     invalid_provider = _make_price(provider=" ")
@@ -128,6 +140,17 @@ def test_filter_valid_prices_excludes_none_provider_and_service() -> None:
     assert result[0].service_name == "express"
 
 
+def test_filter_valid_prices_excludes_prices_rounded_to_zero_after_multiplier() -> None:
+    low_price = _make_price(provider="cdek", price=Decimal("0.40"))
+
+    result = filter_valid_prices(
+        [low_price],
+        price_multiplier=Decimal("0.5"),
+    )
+
+    assert result == []
+
+
 def test_sort_prices_by_price_keeps_equal_price_order_stable() -> None:
     price_a = _make_price(provider="a", price=Decimal("150.00"))
     price_b = _make_price(provider="b", price=Decimal("150.00"))
@@ -143,6 +166,10 @@ def test_filter_and_sort_prices_combines_domain_steps() -> None:
     price_b = _make_price(provider="b", price=Decimal("100.00"))
     invalid = _make_price(provider="", price=Decimal("50.00"))
 
-    result = filter_and_sort_prices([price_a, invalid, price_b])
+    result = filter_and_sort_prices(
+        [price_a, invalid, price_b],
+        price_multiplier=Decimal("1.3"),
+    )
 
     assert [price.provider for price in result] == ["b", "a"]
+    assert [price.price for price in result] == [Decimal("130"), Decimal("286")]