test: refactor test-fs-watchfile

* use `common.mustNotCall()` to confirm callback is not called * reorder modules to conform with test-writing guide * match full error message in `assert.throws()` PR-URL: #13721 Reviewed-By: Refael Ackermann <[email protected]> Reviewed-By: Richard Lau <[email protected]> Reviewed-By: Colin Ihrig <[email protected]> Reviewed-By: Luigi Pinca <[email protected]> Reviewed-By: Gibson Fahnestock <[email protected]> Reviewed-By: James M Snell <[email protected]>

Author: Trott

test/parallel/test-fs-watchfile.js

@@ -1,21 +1,21 @@
 'use strict';
-
 constcommon=require('../common');
+
+constassert=require('assert');
 constfs=require('fs');
 constpath=require('path');
-constassert=require('assert');
 
 // Basic usage tests.
 assert.throws(function(){
 fs.watchFile('./some-file');
-},/"watchFile\(\)"requiresalistenerfunction/);
+},/^Error:"watchFile\(\)"requiresalistenerfunction$/);
 
 assert.throws(function(){
 fs.watchFile('./another-file',{},'bad listener');
-},/"watchFile\(\)"requiresalistenerfunction/);
+},/^Error:"watchFile\(\)"requiresalistenerfunction$/);
 
 assert.throws(function(){
-fs.watchFile(newObject(),common.noop);
+fs.watchFile(newObject(),common.mustNotCall());
 },/Pathmustbeastring/);
 
 constenoentFile=path.join(common.tmpDir,'non-existent-file');