electrum

commit e864fa50882db90df50e6e0240f55197b28097ed
parent f409b5da40e607819f94093f4ca6a91f8a2b71f0
Author: SomberNight <somber.night@protonmail.com>
Date:   Thu, 20 Jun 2019 17:47:43 +0200

coinchooser: tweak heuristic scoring.

transactions without any change now get better scores.
transactions with really small change get worse scores.

Diffstat:
M
electrum/coinchooser.py
 | 
7
++++++-

1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/electrum/coinchooser.py b/electrum/coinchooser.py
@@ -413,8 +413,13 @@ class CoinChooserPrivacy(CoinChooserRandom):
             tx, change_outputs = tx_from_buckets(buckets)
             change = sum(o.value for o in change_outputs)
             # Penalize change not roughly in output range
-            if change < min_change:
+            if change == 0:
+                pass  # no change is great!
+            elif change < min_change:
                 badness += (min_change - change) / (min_change + 10000)
+                # Penalize really small change; under 1 mBTC ~= using 1 more input
+                if change < COIN / 1000:
+                    badness += 1
             elif change > max_change:
                 badness += (change - max_change) / (max_change + 10000)
                 # Penalize large change; 5 BTC excess ~= using 1 more input