fix #4771

electrum/tests/test_util.py

@@ -13,9 +13,12 @@ class TestUtil(SequentialTestCase):
     def test_format_satoshis_negative(self):
         self.assertEqual("-0.00001234", format_satoshis(-1234))
 
-    def test_format_fee(self):
+    def test_format_fee_float(self):
         self.assertEqual("1.7", format_fee_satoshis(1700/1000))
 
+    def test_format_fee_decimal(self):
+        self.assertEqual("1.7", format_fee_satoshis(Decimal("1.7")))
+
     def test_format_fee_precision(self):
         self.assertEqual("1.666",
                          format_fee_satoshis(1666/1000, precision=6))

electrum/util.py

@@ -514,7 +514,7 @@ def format_satoshis(x, num_zeros=0, decimal_point=8, precision=None, is_diff=Fal
     if precision is None:
         precision = decimal_point
     # format string
-    decimal_format = ".0" + str(precision) if precision > 0 else ""
+    decimal_format = "." + str(precision) if precision > 0 else ""
     if is_diff:
         decimal_format = '+' + decimal_format
     # initial result