util: use ES2015+ Object.is to check negative zero

shinnn · jasnell · commit 5ddf72290b30 · 2017-02-16T14:45:59.000-08:00
Use `Object.is` to check whether the value is negative zero or not. Ref: b3e4fc6 PR-URL: #11332 Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl> Reviewed-By: Michaël Zasso <targos@protonmail.com> Reviewed-By: Evan Lucas <evanlucas@me.com> Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com> Reviewed-By: Colin Ihrig <cjihrig@gmail.com> Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Sakthipriyan Vairamani <thechargingvolcano@gmail.com> Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
diff --git a/lib/util.js b/lib/util.js
@@ -561,9 +561,8 @@ function formatValue(ctx, value, recurseTimes) {
 
 
 function formatNumber(ctx, value) {
-  // Format -0 as '-0'. Strict equality won't distinguish 0 from -0,
-  // so instead we use the fact that 1 / -0 < 0 whereas 1 / 0 > 0 .
-  if (value === 0 && 1 / value < 0)
+  // Format -0 as '-0'. Strict equality won't distinguish 0 from -0.
+  if (Object.is(value, -0))
     return ctx.stylize('-0', 'number');
   return ctx.stylize('' + value, 'number');
 }
