Fixed #1597 -- Hardcoded currency choices in MoneyField

This should prevent spurious migrations being generated when updating django-money or babel.

2 files changed, 42 insertions, 0 deletions

diff --git a/foundation/migrations/0006_hardcode_currency_choices.py b/foundation/migrations/0006_hardcode_currency_choices.py
new file mode 100644
index 00000000..68faca8a
--- /dev/null
+++ b/foundation/migrations/0006_hardcode_currency_choices.py
@@ -0,0 +1,30 @@
+# Generated by Django 4.2.14 on 2024-09-26 11:12
+
+from decimal import Decimal
+from django.db import migrations
+import djmoney.models.fields
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('foundation', '0005_alter_approvedgrant_amount_currency_and_more'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='approvedgrant',
+            name='amount',
+            field=djmoney.models.fields.MoneyField(currency_choices=[('AUD', 'Australian Dollar'), ('EUR', 'Euro'), ('NGN', 'Nigerian Naira'), ('USD', 'US Dollar')], decimal_places=2, default=Decimal('0.0'), default_currency='USD', max_digits=10),
+        ),
+        migrations.AlterField(
+            model_name='approvedgrant',
+            name='amount_currency',
+            field=djmoney.models.fields.CurrencyField(choices=[('AUD', 'Australian Dollar'), ('EUR', 'Euro'), ('NGN', 'Nigerian Naira'), ('USD', 'US Dollar')], default='USD', editable=False, max_length=3),
+        ),
+        migrations.AlterField(
+            model_name='meeting',
+            name='treasurer_balance_currency',
+            field=djmoney.models.fields.CurrencyField(choices=[('USD', 'US Dollar')], default='USD', editable=False, max_length=3),
+        ),
+    ]
diff --git a/foundation/models.py b/foundation/models.py
index 4366ae8b..ddbb4517 100644
--- a/foundation/models.py
+++ b/foundation/models.py
@@ -5,6 +5,7 @@ from django.db import models
 from django.urls import reverse
 from django.utils.dateformat import format as date_format
 from djmoney.models.fields import MoneyField
+from djmoney.settings import CURRENCIES
 from docutils.core import publish_parts
 
 from blog.models import BLOG_DOCUTILS_SETTINGS
@@ -131,6 +132,17 @@ class ApprovedGrant(models.Model):
         decimal_places=2,
         default_currency="USD",
         default=Decimal("0.0"),
+        currency_choices=[
+            (c.code, c.name)
+            for i, c in CURRENCIES.items()
+            if c.code
+            in {
+                "USD",
+                "EUR",
+                "AUD",
+                "NGN",
+            }  # This set of currencies was extracted from current usage
+        ],
     )
     approved_at = models.ForeignKey(
         Meeting, related_name="grants_approved", on_delete=models.CASCADE