MPT-17888: fix bidirectional field mapping for consecutive uppercase letters

Add _FIELD_NAME_MAPPINGS (MappingProxyType) in model.py for API fields
that contain two or more consecutive uppercase letters (PPx1, SPxM,
unitLP, totalGT, etc.). The generic camelCase<->snake_case regex cannot
round-trip these correctly, so an explicit lookup table is checked first
in both to_snake_case and to_camel_case.

Affected fields from OpenAPI spec:
- PP*/SP*/LP* price columns (PPx1→ppx1, SPxM→spxm, LPxY→lpxy, ...)
- unit+acronym fields (unitLP→unit_lp, unitPP→unit_pp, unitSP→unit_sp)
- total+acronym fields (totalGT→total_gt, totalPP→total_pp, ...)

PriceListItem model annotations updated to use the corrected names
(ppx1, spxm, lpx1, etc. instead of p_px1, s_px_m, l_px1, ...).
to_dict() round-trip now works correctly for all price columns.

Tests:
- Merged price_list_item price fixture into main fixture for full
  round-trip test coverage
- Added parametrized tests for to_snake_case and to_camel_case with
  consecutive-uppercase fields in tests/unit/models/test_model.py

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: albertsola

.gitignore

@@ -167,6 +167,8 @@ cython_debug/
 .ruff_cache
 .idea
 .openapi/
+openapi/openapi-dev.json
+.github/copilot-instructions.md
 # Makefile
 make/local.mk
 

mpt_api_client/models/model.py

@@ -1,6 +1,7 @@
 import re
 from collections import UserList
 from collections.abc import Iterable
+from types import MappingProxyType
 from typing import Any, Self, get_args, get_origin, override
 
 from mpt_api_client.http.types import Response
@@ -12,9 +13,47 @@
 _SNAKE_CASE_BOUNDARY = re.compile(r"([a-z0-9])([A-Z])")
 _SNAKE_CASE_ACRONYM = re.compile(r"(?<=[A-Z])(?=[A-Z][a-z0-9])")
 
+# Explicit bidirectional mappings for API field names that contain two or more consecutive
+# uppercase letters (e.g. PPx1, unitLP). The generic regex cannot round-trip these correctly,
+# so we maintain an explicit lookup table that is checked before the regex is applied.
+_FIELD_NAME_MAPPINGS: MappingProxyType[str, str] = MappingProxyType({
+    # PP* price columns
+    "PPx1": "ppx1",
+    "PPxM": "ppxm",
+    "PPxY": "ppxy",
+    # SP* price columns
+    "SPx1": "spx1",
+    "SPxM": "spxm",
+    "SPxY": "spxy",
+    # LP* price columns
+    "LPx1": "lpx1",
+    "LPxM": "lpxm",
+    "LPxY": "lpxy",
+    # unit + 2-letter acronym suffix
+    "unitLP": "unit_lp",
+    "unitPP": "unit_pp",
+    "unitSP": "unit_sp",
+    # total + 2-letter acronym suffix
+    "totalGT": "total_gt",
+    "totalPP": "total_pp",
+    "totalSP": "total_sp",
+    "totalST": "total_st",
+})
+
+_FIELD_NAME_MAPPINGS_REVERSE: MappingProxyType[str, str] = MappingProxyType({
+    snake: camel for camel, snake in _FIELD_NAME_MAPPINGS.items()
+})
+
 
 def to_snake_case(key: str) -> str:
-    """Converts a camelCase string to snake_case."""
+    """Converts a camelCase string to snake_case.
+
+    Explicit mappings in ``_FIELD_NAME_MAPPINGS`` take priority over the generic
+    regex for fields that contain two or more consecutive uppercase letters.
+    """
+    mapped = _FIELD_NAME_MAPPINGS.get(key)
+    if mapped is not None:
+        return mapped
     if "_" in key and key.islower():
         return key
     # Common pattern for PascalCase/camelCase conversion
@@ -24,7 +63,14 @@ def to_snake_case(key: str) -> str:
 
 
 def to_camel_case(key: str) -> str:
-    """Converts a snake_case string to camelCase."""
+    """Converts a snake_case string to camelCase.
+
+    Explicit mappings in ``_FIELD_NAME_MAPPINGS_REVERSE`` take priority over the
+    generic logic for fields that contain two or more consecutive uppercase letters.
+    """
+    mapped = _FIELD_NAME_MAPPINGS_REVERSE.get(key)
+    if mapped is not None:
+        return mapped
     parts = key.split("_")
     return parts[0] + "".join(x.title() for x in parts[1:])  # noqa: WPS111 WPS221
 

mpt_api_client/resources/catalog/price_list_items.py

@@ -23,15 +23,15 @@ class PriceListItem(Model):
         markup: Markup percentage.
         margin: Margin percentage.
         unit_sp: Unit sell price.
-        p_px1: Purchase price for 1-year term.
-        p_px_m: Purchase price for monthly term.
-        p_px_y: Purchase price for yearly term.
-        s_px1: Sell price for 1-year term.
-        s_px_m: Sell price for monthly term.
-        s_px_y: Sell price for yearly term.
-        l_px1: List price for 1-year term.
-        l_px_m: List price for monthly term.
-        l_px_y: List price for yearly term.
+        ppx1: Purchase price for 1-year term.
+        ppxm: Purchase price for monthly term.
+        ppxy: Purchase price for yearly term.
+        spx1: Sell price for 1-year term.
+        spxm: Sell price for monthly term.
+        spxy: Sell price for yearly term.
+        lpx1: List price for 1-year term.
+        lpxm: List price for monthly term.
+        lpxy: List price for yearly term.
         price_list: Reference to the parent price list.
         item: Reference to the associated item.
         audit: Audit information (created, updated events).
@@ -45,15 +45,15 @@ class PriceListItem(Model):
     markup: float | None
     margin: float | None
     unit_sp: float | None
-    p_px1: float | None
-    p_px_m: float | None
-    p_px_y: float | None
-    s_px1: float | None
-    s_px_m: float | None
-    s_px_y: float | None
-    l_px1: float | None
-    l_px_m: float | None
-    l_px_y: float | None
+    ppx1: float | None
+    ppxm: float | None
+    ppxy: float | None
+    spx1: float | None
+    spxm: float | None
+    spxy: float | None
+    lpx1: float | None
+    lpxm: float | None
+    lpxy: float | None
     price_list: BaseModel | None
     item: BaseModel | None
     audit: BaseModel | None

tests/unit/models/test_model.py

@@ -2,7 +2,12 @@
 from httpx import Response
 
 from mpt_api_client.models import Meta, Model
-from mpt_api_client.models.model import BaseModel, ModelList, to_snake_case  # noqa: WPS347
+from mpt_api_client.models.model import (  # noqa: WPS347
+    BaseModel,
+    ModelList,
+    to_camel_case,
+    to_snake_case,
+)
 
 
 class AgreementDummy(Model):  # noqa: WPS431
@@ -326,3 +331,33 @@ def test_process_value_scalar_list_elements():
 
     assert isinstance(container.tags, ModelList)
     assert list(container.tags) == ["a", "b", "c"]
+
+
+@pytest.mark.parametrize(
+    ("camel", "snake"),
+    [
+        ("PPx1", "ppx1"),
+        ("SPxM", "spxm"),
+        ("unitLP", "unit_lp"),
+        ("totalGT", "total_gt"),
+    ],
+)
+def test_to_snake_case_consecutive_uppercase(camel, snake):
+    result = to_snake_case(camel)  # act
+
+    assert result == snake
+
+
+@pytest.mark.parametrize(
+    ("snake", "camel"),
+    [
+        ("ppx1", "PPx1"),
+        ("spxm", "SPxM"),
+        ("unit_lp", "unitLP"),
+        ("total_gt", "totalGT"),
+    ],
+)
+def test_to_camel_case_consecutive_uppercase(snake, camel):
+    result = to_camel_case(snake)  # act
+
+    assert result == camel

tests/unit/resources/catalog/test_price_list_items.py

@@ -29,16 +29,6 @@ def price_list_item_data():
         "status": "Active",
         "description": "Item description",
         "reasonForChange": "Price update",
-        "priceList": {"id": "PRC-001", "currency": "USD"},
-        "item": {"id": "ITM-001", "name": "My Item"},
-        "audit": {"created": {"at": "2024-01-01T00:00:00Z"}},
-    }
-
-
-@pytest.fixture
-def price_list_item_price_data():
-    return {
-        "id": "PLI-002",
         "unitLP": 100.0,
         "unitPP": 80.0,
         "markup": 25.0,
@@ -53,6 +43,9 @@ def price_list_item_price_data():
         "LPx1": 100.0,
         "LPxM": 9.0,
         "LPxY": 108.0,
+        "priceList": {"id": "PRC-001", "currency": "USD"},
+        "item": {"id": "ITM-001", "name": "My Item"},
+        "audit": {"created": {"at": "2024-01-01T00:00:00Z"}},
     }
 
 
@@ -92,14 +85,14 @@ def test_price_list_item_primitive_fields(price_list_item_data):
     assert result.to_dict() == price_list_item_data
 
 
-def test_price_list_item_price_fields(price_list_item_price_data):
-    result = PriceListItem(price_list_item_price_data)
+def test_price_list_item_price_fields(price_list_item_data):
+    result = PriceListItem(price_list_item_data)
 
     assert result.unit_lp == pytest.approx(100.0)
     assert result.unit_pp == pytest.approx(80.0)
     assert result.unit_sp == pytest.approx(90.0)
-    assert result.markup == pytest.approx(25.0)
-    assert result.margin == pytest.approx(20.0)
+    assert result.spxm == pytest.approx(8.0)
+    assert result.lpx1 == pytest.approx(100.0)
 
 
 def test_price_list_item_nested_models(price_list_item_data):