1 files changed, 6 insertions, 0 deletions
diff --git a/src/library.js b/src/library.js
index 5c2c858d..0aaef0b2 100644
--- a/src/library.js
+++ b/src/library.js
@@ -2166,6 +2166,12 @@ LibraryManager.library = {
               }
             }
 
+            // Move sign to prefix so we zero-pad after the sign
+            if (argText.charAt(0) == '-') {
+              prefix = '-' + prefix;
+              argText = argText.substr(1);
+            }
+
             // Add padding.
             while (prefix.length + argText.length < width) {
               if (flagLeftAlign) {