002 Pure domain core rules

tests/domain/test_price.py

@@ -0,0 +1,143 @@
+from decimal import Decimal
+
+from app.domain.price import (
+    filter_and_sort_prices,
+    filter_valid_prices,
+    normalize_delivery_request,
+    sort_prices_by_price,
+)
+from app.schemas.request import DeliveryEntity, DeliveryRequest
+from app.schemas.response import DeliveryPrice
+
+
+def _make_price(**overrides) -> DeliveryPrice:
+    payload = {
+        "provider": "provider-a",
+        "service_name": "standard",
+        "price": Decimal("100.00"),
+        "currency": "RUB",
+        "delivery_days_min": 2,
+        "delivery_days_max": 4,
+    }
+    payload.update(overrides)
+    return DeliveryPrice.model_construct(**payload)
+
+
+def _make_request(**overrides) -> DeliveryRequest:
+    payload = {
+        "entity": DeliveryEntity.INDIVIDUAL,
+        "from_city": "  Moscow  ",
+        "to_city": "  Saint Petersburg  ",
+        "weight_kg": 1.235,
+        "length_cm": 10.04,
+        "width_cm": 20.05,
+        "height_cm": 30.06,
+    }
+    payload.update(overrides)
+    return DeliveryRequest(**payload)
+
+
+def test_normalize_delivery_request_applies_rules_without_side_effects() -> None:
+    request = _make_request()
+
+    normalized = normalize_delivery_request(request, weight_round_scale=2)
+
+    assert normalized is not request
+    assert normalized.from_city == "Moscow"
+    assert normalized.to_city == "Saint Petersburg"
+    assert normalized.weight_kg == Decimal("1.24")
+    assert normalized.length_cm == Decimal("10.0")
+    assert normalized.width_cm == Decimal("20.1")
+    assert normalized.height_cm == Decimal("30.1")
+    assert request.from_city == "  Moscow  "
+
+
+def test_normalize_delivery_request_handles_normalization_boundaries() -> None:
+    request = _make_request(
+        weight_kg=0.0001,
+        length_cm=0.01,
+        width_cm=0.04,
+        height_cm=0.15,
+    )
+
+    low_scale = normalize_delivery_request(request, weight_round_scale=-5)
+    high_scale = normalize_delivery_request(request, weight_round_scale=99)
+
+    assert low_scale.weight_kg == Decimal("0.01")
+    assert low_scale.length_cm == Decimal("0.1")
+    assert low_scale.width_cm == Decimal("0.1")
+    assert low_scale.height_cm == Decimal("0.2")
+    assert high_scale.weight_kg == Decimal("0.01")
+
+
+def test_filter_valid_prices_handles_empty_input() -> None:
+    assert filter_valid_prices([]) == []
+    assert filter_and_sort_prices([]) == []
+
+
+def test_filter_valid_prices_excludes_invalid_records() -> None:
+    valid = _make_price(provider=" cdek ", service_name=" express ", currency="rub")
+    invalid_provider = _make_price(provider=" ")
+    invalid_price = _make_price(price=Decimal("-1.00"))
+    invalid_currency = _make_price(currency="RUR1")
+    invalid_range = _make_price(delivery_days_min=5, delivery_days_max=3)
+
+    result = filter_valid_prices(
+        [
+            valid,
+            invalid_provider,
+            invalid_price,
+            invalid_currency,
+            invalid_range,
+            {"not": "a price"},
+        ]
+    )
+
+    assert len(result) == 1
+    assert result[0].provider == "cdek"
+    assert result[0].service_name == "express"
+    assert result[0].currency == "RUB"
+
+
+def test_filter_valid_prices_excludes_non_finite_prices() -> None:
+    valid = _make_price(provider="cdek", price=Decimal("199.00"))
+    invalid_nan = _make_price(price=Decimal("NaN"))
+    invalid_inf = _make_price(price=Decimal("Infinity"))
+    invalid_neg_inf = _make_price(price=Decimal("-Infinity"))
+
+    result = filter_valid_prices([invalid_nan, invalid_inf, invalid_neg_inf, valid])
+
+    assert len(result) == 1
+    assert result[0].provider == "cdek"
+
+
+def test_filter_valid_prices_excludes_none_provider_and_service() -> None:
+    valid = _make_price(provider="cdek", service_name="express")
+    invalid_provider_none = _make_price(provider=None)
+    invalid_service_none = _make_price(service_name=None)
+
+    result = filter_valid_prices([invalid_provider_none, invalid_service_none, valid])
+
+    assert len(result) == 1
+    assert result[0].provider == "cdek"
+    assert result[0].service_name == "express"
+
+
+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"))
+    price_c = _make_price(provider="c", price=Decimal("99.99"))
+
+    sorted_prices = sort_prices_by_price([price_a, price_b, price_c])
+
+    assert [price.provider for price in sorted_prices] == ["c", "a", "b"]
+
+
+def test_filter_and_sort_prices_combines_domain_steps() -> None:
+    price_a = _make_price(provider="a", price=Decimal("220.00"))
+    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])
+
+    assert [price.provider for price in result] == ["b", "a"]