test: refactor test-crypto-random

* specify constructor for assert.throws()
* load additional modules only if crypto check passes
* normalize some potentially confusing indentation
* provided actual first and expected second in assertions
PR-URL: #10232
Reviewed-By: Prince John Wesley <princejohnwesley@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>

Author: Trott

test/parallel/test-crypto-random.js

@@ -1,37 +1,28 @@
 'use strict';
 constcommon=require('../common');
-constassert=require('assert');
 
 if(!common.hasCrypto){
 common.skip('missing crypto');
 return;
 }
+constassert=require('assert');
 constcrypto=require('crypto');
 
 crypto.DEFAULT_ENCODING='buffer';
 
 // bump, we register a lot of exit listeners
 process.setMaxListeners(256);
 
-[crypto.randomBytes,
-crypto.pseudoRandomBytes
-].forEach(function(f){
-[-1,
-undefined,
-null,
-false,
-true,
-{},
-[]
-].forEach(function(value){
-assert.throws(function(){f(value);});
-assert.throws(function(){f(value,function(){});});
+[crypto.randomBytes,crypto.pseudoRandomBytes].forEach(function(f){
+[-1,undefined,null,false,true,{},[]].forEach(function(value){
+assert.throws(function(){f(value);},TypeError);
+assert.throws(function(){f(value,function(){});},TypeError);
 });
 
 [0,1,2,4,16,256,1024].forEach(function(len){
 f(len,common.mustCall(function(ex,buf){
-assert.strictEqual(null,ex);
-assert.strictEqual(len,buf.length);
+assert.strictEqual(ex,null);
+assert.strictEqual(buf.length,len);
 assert.ok(Buffer.isBuffer(buf));
 }));
 });