Merge pull request #108 from SamuelJennings/main

convert numeric types to str before calling Decimal

AUTHORS.rst

@@ -9,4 +9,4 @@ Contributors
 * Alex Bhandari <[email protected]>
 * Jonas Haag <[email protected]>
 * Igor Kozyrenko <[email protected]>
-* Samuel Scott Jennings <[email protected]>
+* Samuel Jennings <[email protected]>

CHANGELOG.rst

@@ -3,6 +3,10 @@ Changelog
 =========
 
 
+Version 0.7.2
+=============
+- fix conversion of number input to DecimalField (`issue #106 <https://github.com/CarliJoy/django-pint/issues/106>`)
+
 Version 0.7.1
 =============
 -  fix wrong unit display in widget (`issue #43 <https://github.com/CarliJoy/django-pint/issues/43>`_)

src/quantityfield/fields.py

@@ -366,12 +366,13 @@ class PositiveIntegerQuantityField(QuantityFieldMixin, models.PositiveIntegerFie
 
 
 class DecimalQuantityFormField(QuantityFormFieldMixin, forms.DecimalField):
-    to_number_type = Decimal
+
+    def to_number_type(self, x: object) -> Decimal:
+        return Decimal(str(x))
 
 
 class DecimalQuantityField(QuantityFieldMixin, models.DecimalField):
     form_field_class = DecimalQuantityFormField
-    to_number_type = Decimal
 
     def __init__(
         self,
@@ -418,6 +419,9 @@ def __init__(
             **kwargs,
         )
 
+    def to_number_type(self, x: object) -> Decimal:
+        return Decimal(str(x))
+
     def get_db_prep_save(self, value, connection) -> Decimal:
         """
         Get Value that shall be saved to database, make sure it is transformed

tests/test_field.py

@@ -16,6 +16,7 @@
 from quantityfield.fields import (
     BigIntegerQuantityField,
     DecimalQuantityField,
+    DecimalQuantityFormField,
     IntegerQuantityField,
     PositiveIntegerQuantityField,
     QuantityField,
@@ -452,6 +453,16 @@ class TestDecimalFieldSave(FloatLikeFieldSaveTestBase, TestCase):
     OUNCES_IN_GRAM = Decimal("283.50")
     EXPECTED_TYPE = Decimal
 
+    def test_stores_value_in_base_units(self):
+        field = self.MODEL._meta.get_field("weight")
+        expected = Decimal("2.1")
+        func = field.to_number_type
+        self.assertIsInstance(func(2.1), Decimal)
+        self.assertEqual(func(2.1), expected)  # test float
+        self.assertEqual(func("2.1"), expected)  # test string
+        self.assertEqual(func(Decimal("2.1")), expected)  # test Decimal
+        self.assertEqual(func(2), Decimal("2"))  # test Int
+
 
 class IntLikeFieldSaveTestBase(FieldSaveTestBase):
     DEFAULT_WEIGHT_STR = "100"
@@ -514,3 +525,24 @@ def test_comparison_with_quantity(self):
     def test_comparison_with_quantity_respects_units(self):
         qs = self.MODEL.objects.filter(weight__gt=self.COMPARE_QUANTITY)
         self.assertNotIn(self.lightest, qs)
+
+
+class TestDecimalQuantityFormField(TestCase):
+
+    def test_to_number_type_returns_decimal(self):
+        field = DecimalQuantityFormField(base_units="gram")
+        expected = Decimal("2.1")
+        func = field.to_number_type
+        self.assertIsInstance(func(2.1), Decimal)
+        self.assertEqual(func(2.1), expected)  # test float
+        self.assertEqual(func("2.1"), expected)  # test string
+        self.assertEqual(func(Decimal("2.1")), expected)  # test Decimal
+        self.assertEqual(func(2), Decimal("2"))  # test Int
+
+    def test_saves_correct_decimal_precision(self):
+        field = DecimalQuantityFormField(base_units="gram")
+        expected = Decimal("2.1")
+        self.assertEqual(field.clean(2.1).magnitude, expected)  # test float
+        self.assertEqual(field.clean("2.1").magnitude, expected)  # test string
+        self.assertEqual(field.clean(expected).magnitude, expected)  # test Decimal
+        self.assertEqual(field.clean(2).magnitude, Decimal("2"))  # test Int