Add custom to_python function to allow localised number inputs to Requested amount field. Add custom prepare_value to make the widget use the locale correct decimal seperator.

Author: frjo

hypha/apply/funds/blocks.py

@@ -1,6 +1,7 @@
 import json
 
 from django import forms
+from django.utils.formats import get_format
 from django.utils.translation import gettext_lazy as _
 from wagtail import blocks
 
@@ -17,6 +18,66 @@
 from hypha.apply.utils.templatetags.apply_tags import format_number_as_currency
 
 
+class LocalizedFloatField(forms.FloatField):
+    """
+    FloatField that accepts locale-formatted numbers without relying on the
+    active locale. Assumes at most two decimal places (no cents sub-divisions),
+    which makes the separator role unambiguous:
+
+    - Both . and , present: whichever comes last is the decimal separator.
+    - Single separator with exactly 3 digits after it: thousands separator.
+    - Single separator with 1 or 2 digits after it: decimal separator.
+    - Multiple identical separators: all are thousands separators.
+    """
+
+    def to_python(self, value):
+        if value not in self.empty_values:
+            value = str(value).strip()
+            has_dot = "." in value
+            has_comma = "," in value
+
+            if has_dot and has_comma:
+                # Both present — whichever appears last is the decimal.
+                if value.rfind(".") > value.rfind(","):
+                    value = value.replace(",", "")  # e.g. "1,000.50" (comma-thousands)
+                else:
+                    value = value.replace(".", "").replace(
+                        ",", "."
+                    )  # e.g. "1.000,50" (dot-thousands)
+            elif has_comma:
+                parts = value.split(",")
+                if len(parts) > 2 or len(parts[1]) == 3:
+                    value = value.replace(
+                        ",", ""
+                    )  # e.g. "10,000" or "1,000,000" (comma-thousands)
+                else:
+                    value = value.replace(
+                        ",", "."
+                    )  # e.g. "10000,00" or "1,5" (comma-decimal)
+            elif has_dot:
+                parts = value.split(".")
+                if len(parts) > 2 or len(parts[1]) == 3:
+                    value = value.replace(
+                        ".", ""
+                    )  # e.g. "10.000" or "1.000.000" (dot-thousands)
+                # else: already a valid decimal, e.g. "10.5" or "10.00" (dot-decimal)
+
+        result = super().to_python(value)
+        if result is not None and result == int(result):
+            return int(result)
+        return result
+
+    def prepare_value(self, value):
+        # Format a stored numeric value using the active locale's decimal
+        # separator so the widget displays e.g. "10000,5" in comma-decimal
+        # locales rather than the Python default "10000.5". String values
+        # (mid-form re-display after a validation error) are returned unchanged.
+        if isinstance(value, float):
+            decimal_sep = get_format("DECIMAL_SEPARATOR")
+            return str(value).replace(".", decimal_sep)
+        return value
+
+
 class ApplicationSingleIncludeFieldBlock(SingleIncludeBlock):
     pass
 
@@ -51,13 +112,22 @@ def get_field_kwargs(self, struct_value):
 class ValueBlock(ApplicationSingleIncludeFieldBlock):
     name = "value"
     description = "The value of the project"
-    widget = forms.NumberInput(attrs={"min": 0})
-    field_class = forms.FloatField
+    # TextInput + inputmode="decimal" lets us handle locale-specific separators
+    # server-side. <input type="number"> formats/validates using the *browser*
+    # locale which differs from Django's active locale and behaves inconsistently
+    # across browsers, causing e.g. German "10.000" to be stored as 10.
+    widget = forms.TextInput(attrs={"inputmode": "decimal"})
+    field_class = LocalizedFloatField
 
     class Meta:
         label = _("Requested amount")
         icon = "decimal"
 
+    def get_field_kwargs(self, struct_value):
+        kwargs = super().get_field_kwargs(struct_value)
+        kwargs["min_value"] = 0
+        return kwargs
+
     def prepare_data(self, value, data, serialize):
         if not data:
             return data

hypha/apply/funds/tests/test_blocks.py

@@ -0,0 +1,101 @@
+from django.core.exceptions import ValidationError
+from django.test import TestCase
+from django.utils import translation
+
+from hypha.apply.funds.blocks import LocalizedFloatField
+
+
+class TestLocalizedFloatField(TestCase):
+    def setUp(self):
+        self.field = LocalizedFloatField()
+
+    # --- Both separators present: last one is the decimal ---
+
+    def test_dot_thousands_comma_decimal(self):
+        """1.000,50 → 1000.5 (dot-thousands, comma-decimal)"""
+        self.assertAlmostEqual(self.field.clean("1.000,50"), 1000.5)
+
+    def test_comma_thousands_dot_decimal(self):
+        """1,000.50 → 1000.5 (comma-thousands, dot-decimal)"""
+        self.assertAlmostEqual(self.field.clean("1,000.50"), 1000.5)
+
+    # --- Multiple identical separators: all thousands ---
+
+    def test_dot_thousands_millions(self):
+        """1.000.000 → 1000000 (dot-thousands)"""
+        self.assertAlmostEqual(self.field.clean("1.000.000"), 1_000_000)
+
+    def test_comma_thousands_millions(self):
+        """1,000,000 → 1000000 (comma-thousands)"""
+        self.assertAlmostEqual(self.field.clean("1,000,000"), 1_000_000)
+
+    # --- Single separator: 3 digits after = thousands, 1-2 digits = decimal ---
+
+    def test_dot_thousands(self):
+        """10.000 → 10000 (dot-thousands)"""
+        self.assertAlmostEqual(self.field.clean("10.000"), 10_000)
+
+    def test_comma_thousands(self):
+        """10,000 → 10000 (comma-thousands)"""
+        self.assertAlmostEqual(self.field.clean("10,000"), 10_000)
+
+    def test_dot_decimal(self):
+        """10.50 → 10.5 (dot-decimal)"""
+        self.assertAlmostEqual(self.field.clean("10.50"), 10.5)
+
+    def test_comma_decimal(self):
+        """10,50 → 10.5 (comma-decimal)"""
+        self.assertAlmostEqual(self.field.clean("10,50"), 10.5)
+
+    def test_comma_decimal_one_digit(self):
+        """1,5 → 1.5 (comma-decimal)"""
+        self.assertAlmostEqual(self.field.clean("1,5"), 1.5)
+
+    def test_large_amount_comma_decimal(self):
+        """10000,00 → 10000.0 (comma-decimal, no thousands separator)"""
+        self.assertAlmostEqual(self.field.clean("10000,00"), 10_000.0)
+
+    # --- Plain numbers and integer/float return type ---
+
+    def test_plain_integer(self):
+        self.assertEqual(self.field.clean("10000"), 10_000)
+        self.assertIsInstance(self.field.clean("10000"), int)
+
+    def test_whole_number_returns_int(self):
+        """10000.00 and 10000,00 should be stored as 10000, not 10000.0"""
+        self.assertIsInstance(self.field.clean("10000.00"), int)
+        self.assertIsInstance(self.field.clean("10000,00"), int)
+
+    def test_fractional_number_returns_float(self):
+        """10000.50 should be stored as 10000.5, not 10000"""
+        result = self.field.clean("10000.50")
+        self.assertIsInstance(result, float)
+        self.assertAlmostEqual(result, 10000.5)
+
+    def test_zero(self):
+        self.assertEqual(self.field.clean("0"), 0)
+        self.assertIsInstance(self.field.clean("0"), int)
+
+    # --- prepare_value: display stored value in locale format ---
+
+    def test_prepare_value_uses_locale_decimal_separator(self):
+        """Stored float 10000.5 should display as "10000,5" in a comma-decimal locale."""
+        with translation.override("sv"):
+            self.assertEqual(self.field.prepare_value(10000.5), "10000,5")
+
+    def test_prepare_value_integer_unchanged(self):
+        """Stored int 10000 should display as 10000 (no decimal separator added)."""
+        with translation.override("sv"):
+            self.assertEqual(self.field.prepare_value(10000), 10000)
+
+    def test_prepare_value_string_unchanged(self):
+        """A string value (re-display after validation error) is not reformatted."""
+        with translation.override("sv"):
+            self.assertEqual(self.field.prepare_value("10000,5"), "10000,5")
+
+    # --- Validation ---
+
+    def test_negative_rejected_when_min_value_set(self):
+        field = LocalizedFloatField(min_value=0)
+        with self.assertRaises(ValidationError):
+            field.clean("-1")