json parse is insane

every project i’ve been in so far had the same stupid bug with JSON.parse. at the beginning someone got a string instead of an object and they used JSON.parse to convert it to an object.
then after a while, someone fixed it upstream, and now JSON.parse is getting an object and fails with a very cryptic error message.

i always make sure my code is safe and i write it as such:

item = result.data;
if ( typeof(item) === 'string' ) {   
   item = JSON.parse(item);  
}  

however, each time i write this piece of code, it seems to me like it is a bug in javascript.

seems to me like 1 of 2 things should happen:

• javaScript should throw an error you cannot parse an object
• javaScript should simply return the object as there’s nothing to parse.

i think the latter is better and more aligned with the rest of JavaScript behavior. but what happens now is simply insane - JavaScript implicitly converts the object toString and tries to parse that.
which is insane because nowhere in the world of JavaScript is toString meant to return a JSON.
this is why you have JSON.stringify to begin with.
so if anything at all JSON.parse should use JSON.stringify instead of toString

• but what would be the point of that? simply return the object you got.

another reason why this is insane is that toString returns [object Object] which ironically enough starts like an array (which is a valid input for JSON.parse) and so the error developers get is invalid token o.
and last reason for insanity is that this has been the situation for quite a while now.

i tried to see what other libraries are doing with this insanity : turns out that JQuery doesn’t try to fix this issue. $.JSONparse is just as insane.
lodash does not offer anything in this matter.
i know that angular behaves nicely - like i expected - but for projects that don’t use angular, it would be an overkill to use angular just for this.
other than that, I could not find any references to this problem anywhere.
this problem seems to me a lot like the console.log problem - that it does not exist in some browsers - and should have a similar fix.

my current recommendation to fix this issue by replacing JSON.parse method with something like

JSON.parseString = JSON.parse  
JSON.parse = function ( o ) {  
    if ( typeof(o)  === 'string' ){   
       return JSON.parseString.apply(arguments);  
    } else {   
        return o;   
    }    
}  

but i keep getting strong objections on such a solution as it is intrusive. what do you think? leave comments below.

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