Create deflator strict mode and explicit casts flags with tests and default universal fallback unwrapper

tests/test_explicit_cast_deflator.py

@@ -0,0 +1,94 @@
+from dataclasses import dataclass
+
+import pytest
+
+from megasniff import SchemaDeflatorGenerator
+from megasniff.exceptions import FieldValidationException
+
+
+def test_global_explicit_casts_basic():
+    class A:
+        a: int
+
+        def __init__(self, a):
+            self.a = a
+
+    defl = SchemaDeflatorGenerator(explicit_casts=True)
+    fn = defl.schema_to_deflator(A)
+    a = fn(A(42))
+
+    assert a['a'] == 42
+
+    a = fn(A(42.0))
+    assert a['a'] == 42
+
+    a = fn(A('42'))
+    assert a['a'] == 42
+
+    with pytest.raises(TypeError):
+        fn(A(['42']))
+
+
+def test_global_explicit_casts_basic_override():
+    class A:
+        a: int
+
+        def __init__(self, a):
+            self.a = a
+
+    defl = SchemaDeflatorGenerator(explicit_casts=False)
+    fn = defl.schema_to_deflator(A, explicit_casts_override=True)
+    a = fn(A(42))
+
+    assert a['a'] == 42
+
+    a = fn(A(42.0))
+    assert a['a'] == 42
+
+    a = fn(A('42'))
+    assert a['a'] == 42
+
+    with pytest.raises(TypeError):
+        fn(A(['42']))
+
+
+def test_global_explicit_casts_list():
+    @dataclass
+    class A:
+        a: list[int]
+
+    defl = SchemaDeflatorGenerator(explicit_casts=True)
+    fn = defl.schema_to_deflator(A)
+    a = fn(A([42]))
+
+    assert a['a'] == [42]
+
+    a = fn(A([42.0, 42]))
+    assert len(a['a']) == 2
+    assert a['a'][0] == 42
+    assert a['a'][1] == 42
+
+
+def test_global_explicit_casts_circular():
+    @dataclass
+    class A:
+        a: list[int]
+
+    @dataclass
+    class B:
+        b: list[A | int]
+
+    defl = SchemaDeflatorGenerator(explicit_casts=True)
+    fn = defl.schema_to_deflator(B)
+    b = fn(B([A([]), 42]))
+
+    assert len(b['b']) == 2
+    assert isinstance(b['b'][0], dict)
+    assert len(b['b'][0]['a']) == 0
+    assert isinstance(b['b'][1], int)
+
+    b = fn(B([42.0]))
+    assert b['b'][0] == 42
+
+    b = fn(B([A([1.1])]))
+    assert b['b'][0]['a'][0] == 1