then you have to use a style checker, like JSLintjsLint. Also, check jsHint or Google Closure Linter. Which one of those? It's up to you to make a choice. To help you with that, here are a few notes:
Style
Google Closure Linter follows Google JavaScript Style Guide, known to be cleverly done. Using a well-known style for JavaScript or any of six other languages is a good idea: when you share your code or hire a new developer, chances are they are already familiar with this style.
Many developers are familiar with Douglas Crockford style as well. This style is explained in detail in JavaScript: The Good Parts, a book worth be bought by anyone who works with JavaScript.
As for jsHint, I can't really find what conventions are used, and the website itself seems to avoid talking about that subject. Maybe I missed something.
Support by IDEs
Both jsLint and jsHint are supported by PhpStorm. This is also the case of Google Closure Linter.
Environment
Google Closure Linter is one of a series of tools. If you're already using Google Closure Compiler or Google Closure Library, it would be preferable to chose Closure Linter above other tools.
Strictness
jsLint is known to be strict. jsHint is more permissive, which is not always a good thing. For example, one of the reasons to fork jsLint for jsHint is explained in an article which shows bad code which will also validate this sortproduce a error in jsLint, but not in jsHint:
/*global jQuery */
// Example taken from jQuery 1.4.2 source
jQuery.extend({
/* ... */
isEmptyObject: function( obj ) {
for ( var name in obj ) {
return false;
}
return true;
}
/* ... */
});
The code is bad, because it looks like JavaScript has block scope, while it hasn't. See JavaScript: The Good Parts, p. 102, Appendix A: Awful Parts, Scope. In other words, looking at the code without knowing the language, we expect name to not being visible outside the loop, while it will remain visible.
As for Google Closure Linter, I believe that it's somewhere in the middle between jsLint and jsHint, but I haven't enough information to support that.
Conclusion
I would avoid jsHint: it's too permissive, meaning that it would not find potential bugs the other linters would detect. The style guide which is used is difficult to find.
Among jsLint and Google Closure Linter, the choice isn't obvious. Both are written by experts, both follow strict, well described style guide already followed by thousands of thingsdevelopers. Use both for some time, then pick one which is more practical for you.
