From 486d2bb51b3ef9f4d9f8f4fa40a5e0e652525b33 Mon Sep 17 00:00:00 2001
From: Jeremy Stretch <jstretch@netboxlabs.com>
Date: Wed, 12 Mar 2025 12:58:59 -0400
Subject: [PATCH] Fixes #18869: Ensure to_meters() always returns a clean
 decimal value

---
 netbox/utilities/conversion.py             | 16 +++----
 netbox/utilities/tests/test_conversions.py | 53 ++++++++++++++++++++++
 2 files changed, 61 insertions(+), 8 deletions(-)
 create mode 100644 netbox/utilities/tests/test_conversions.py

diff --git a/netbox/utilities/conversion.py b/netbox/utilities/conversion.py
index 6ce32212a..35a8bad5f 100644
--- a/netbox/utilities/conversion.py
+++ b/netbox/utilities/conversion.py
@@ -37,9 +37,9 @@ def to_grams(weight, unit) -> int:
     )
 
 
-def to_meters(length, unit):
+def to_meters(length, unit) -> Decimal:
     """
-    Convert the given length to meters.
+    Convert the given length to meters, returning a Decimal value.
     """
     try:
         if length < 0:
@@ -48,17 +48,17 @@ def to_meters(length, unit):
         raise TypeError(_("Invalid value '{length}' for length (must be a number)").format(length=length))
 
     if unit == CableLengthUnitChoices.UNIT_KILOMETER:
-        return length * 1000
+        return round(Decimal(length * 1000), 4)
     if unit == CableLengthUnitChoices.UNIT_METER:
-        return length
+        return round(Decimal(length), 4)
     if unit == CableLengthUnitChoices.UNIT_CENTIMETER:
-        return length / 100
+        return round(Decimal(length / 100), 4)
     if unit == CableLengthUnitChoices.UNIT_MILE:
-        return length * Decimal(1609.344)
+        return round(length * Decimal(1609.344), 4)
     if unit == CableLengthUnitChoices.UNIT_FOOT:
-        return length * Decimal(0.3048)
+        return round(length * Decimal(0.3048), 4)
     if unit == CableLengthUnitChoices.UNIT_INCH:
-        return length * Decimal(0.0254)
+        return round(length * Decimal(0.0254), 4)
     raise ValueError(
         _("Unknown unit {unit}. Must be one of the following: {valid_units}").format(
             unit=unit,
diff --git a/netbox/utilities/tests/test_conversions.py b/netbox/utilities/tests/test_conversions.py
new file mode 100644
index 000000000..ed8955f96
--- /dev/null
+++ b/netbox/utilities/tests/test_conversions.py
@@ -0,0 +1,53 @@
+from decimal import Decimal
+
+from dcim.choices import CableLengthUnitChoices
+from netbox.choices import WeightUnitChoices
+from utilities.conversion import to_grams, to_meters
+from utilities.testing.base import TestCase
+
+
+class ConversionsTest(TestCase):
+
+    def test_to_grams(self):
+        self.assertEqual(
+            to_grams(1, WeightUnitChoices.UNIT_KILOGRAM),
+            1000
+        )
+        self.assertEqual(
+            to_grams(1, WeightUnitChoices.UNIT_GRAM),
+            1
+        )
+        self.assertEqual(
+            to_grams(1, WeightUnitChoices.UNIT_POUND),
+            453
+        )
+        self.assertEqual(
+            to_grams(1, WeightUnitChoices.UNIT_OUNCE),
+            28
+        )
+
+    def test_to_meters(self):
+        self.assertEqual(
+            to_meters(1, CableLengthUnitChoices.UNIT_KILOMETER),
+            Decimal('1000')
+        )
+        self.assertEqual(
+            to_meters(1, CableLengthUnitChoices.UNIT_METER),
+            Decimal('1')
+        )
+        self.assertEqual(
+            to_meters(1, CableLengthUnitChoices.UNIT_CENTIMETER),
+            Decimal('0.01')
+        )
+        self.assertEqual(
+            to_meters(1, CableLengthUnitChoices.UNIT_MILE),
+            Decimal('1609.344')
+        )
+        self.assertEqual(
+            to_meters(1, CableLengthUnitChoices.UNIT_FOOT),
+            Decimal('0.3048')
+        )
+        self.assertEqual(
+            to_meters(1, CableLengthUnitChoices.UNIT_INCH),
+            Decimal('0.0254')
+        )