assert: replace many if's with if-else statement

Replace multiple mutually exclusive `if` statements with if-else
statements.

PR-URL: #14043
Reviewed-By: Refael Ackermann <refack@gmail.com>
Reviewed-By: Franziska Hinkelmann <franziska.hinkelmann@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: David Cai <davidcai1993@yahoo.com>

lib/assert.js

@@ -62,18 +62,20 @@ function innerFail(actual, expected, message, operator, stackStartFunction) {
 }
 
 function fail(actual, expected, message, operator, stackStartFunction) {
-  if (arguments.length === 0) {
+  const argsLen = arguments.length;
+
+  if (argsLen === 0) {
     message = 'Failed';
-  }
-  if (arguments.length === 1) {
+  } else if (argsLen === 1) {
     message = actual;
     actual = undefined;
-  }
-  if (arguments.length === 2) {
+  } else if (argsLen === 2) {
     operator = '!=';
   }
+
   innerFail(actual, expected, message, operator, stackStartFunction || fail);
 }
+
 assert.fail = fail;
 
 // The AssertionError is defined in internal/error.