util: don't bother checking types before objectToString()

Author: Fishrock123

lib/util.js

@@ -546,8 +546,7 @@ exports.isUndefined = deprecate(isUndefined,
 
 // note: the isRegExp function is still used here in util
 function isRegExp(re) {
-  return re !== null && typeof re === 'object' &&
-         objectToString(re) === '[object RegExp]';
+  return objectToString(re) === '[object RegExp]';
 }
 exports.isRegExp = deprecate(isRegExp,
     'util.isRegExp is deprecated, please use a user-land alternative.');
@@ -560,14 +559,12 @@ exports.isObject = deprecate(isObject,
 
 // still used in assert and fs
 function isDate(d) {
-  return d !== null && typeof d === 'object' &&
-         objectToString(d) === '[object Date]';
+  return objectToString(d) === '[object Date]';
 }
 exports.isDate = isDate;
 
 function isError(e) {
-  return e !== null && typeof e === 'object' &&
-      (objectToString(e) === '[object Error]' || e instanceof Error);
+  return objectToString(e) === '[object Error]' || e instanceof Error;
 }
 exports.isError = deprecate(isError,
     'util.isError is deprecated, please use a user-land alternative.');