Add group parameter feature

tests/test_group.py

@@ -0,0 +1,74 @@
+import pytest
+
+from aiohttp_pydantic.injectors import (
+    Group,
+    _get_group_signature,
+    _unpack_group_in_signature,
+    DuplicateNames,
+)
+
+
+def test_get_group_signature_with_a2b2():
+    class A(Group):
+        a: int = 1
+
+    class B(Group):
+        b: str = "b"
+
+    class B2(B):
+        b: str = "b2"  # Overwrite default value
+
+    class A2(A):
+        a: int  # Remove default value
+
+    class A2B2(A2, B2):
+        ab2: float
+
+    assert ({"ab2": float, "a": int, "b": str}, {"b": "b2"}) == _get_group_signature(
+        A2B2
+    )
+
+
+def test_unpack_group_in_signature():
+    class PaginationGroup(Group):
+        page: int
+        page_size: int = 20
+
+    args = {"pagination": PaginationGroup, "name": str, "age": int}
+
+    default = {"age": 18}
+
+    _unpack_group_in_signature(args, default)
+
+    assert args == {"page": int, "page_size": int, "name": str, "age": int}
+
+    assert default == {"age": 18, "page_size": 20}
+
+
+def test_unpack_group_in_signature_with_duplicate_error():
+    class PaginationGroup(Group):
+        page: int
+        page_size: int = 20
+
+    args = {"pagination": PaginationGroup, "page": int, "age": int}
+
+    with pytest.raises(DuplicateNames) as e_info:
+        _unpack_group_in_signature(args, {})
+
+    assert e_info.value.group is PaginationGroup
+    assert e_info.value.attr_name == "page"
+
+
+def test_unpack_group_in_signature_with_parameters_overwrite():
+    class PaginationGroup(Group):
+        page: int = 0
+        page_size: int = 20
+
+    args = {"page": PaginationGroup, "age": int}
+
+    default = {}
+    _unpack_group_in_signature(args, default)
+
+    assert args == {"page": int, "page_size": int, "age": int}
+
+    assert default == {"page": 0, "page_size": 20}