How to set correct fileName for exceptions thrown from a function in a Function object

[Tim Fox]

On 18/02/15 13:13, A. Sundararajan wrote:
>
> Hi Tim,
>
> It was added in 8u20 if I recall right.
>
> jjs -version
> nashorn 1.8.0_40
> jjs>
> jjs> eval("f() //# sourceURL=t.js")
> t.js:1 ReferenceError: "f" is not defined
> jjs> eval("g() //@ sourceURL=g.js")
> g.js:1 ReferenceError: "g" is not defined
>
> I think your file has "// #sourceURL=wibble.js". Please try changing 
> it as "//# sourceFile=wibble.js"

Ok, I am confused now... I have tried both #sourceURL (which most of the 
google hits say to use) and #sourceFile and neither seem to work ;)

I've also tried @sourceURL which some other links say to use. (Yay for 
consistency ;) )

Nothing seems to work so far.

I am using nashorn 1.8.0_25 which is the latest version in the 
production Oracle JDK afaict. Do I have to use OpenJDK to get these 
changes? I don't think this will be an option as most of users use the 
Oracle JDK.

>
> See also: 
> https://developer.mozilla.org/en-US/docs/Tools/Debugger/How_to/Debug_eval_sources
>
> -Sundar
>
> On Wednesday 18 February 2015 06:14 PM, Tim Fox wrote:
>> Hi Sundar,
>>
>> I tried the sourceURL trick:
>>
>> https://gist.github.com/purplefox/60619067006c3cc3eaee
>>
>> But it doesn't seem to work. I suspect because the parsing of the 
>> eval fails before it gets to the last line (?) :(
>>
>> I'm going to give a go with load()...
>>
>> On 18/02/15 10:11, A. Sundararajan wrote:
>>> you can use
>>>
>>> 1) "load" from object - object with name and script properties.
>>>
>>> 2) or use 'eval' naming // #sourceURL comment
>>>
>>> as mentioned here:
>>>
>>> http://mail.openjdk.java.net/pipermail/nashorn-dev/2014-July/003174.html 
>>>
>>>
>>> Can code for body of module function be something like 
>>> "eval(readScriptAsText() + "\n// #sourceURL=" + name)" ?
>>>
>>> Hope this helps,
>>> -Sundar
>>>
>>> On Wednesday 18 February 2015 03:30 PM, Tim Fox wrote:
>>>> I've added a simple reproducer that you can run in the repl:
>>>>
>>>> https://gist.github.com/purplefox/b03a2a6263c26e3206da
>>>>
>>>> Another observation is that line number is reported as 6, when it 
>>>> should be 5 (assuming the first line is line 1 which is normal 
>>>> convention afaik)
>>>>
>>>> On 18/02/15 09:40, Tim Fox wrote:
>>>>> Hi all,
>>>>>
>>>>> I'm currently using a CommonJS/npm modules require implementation 
>>>>> (npm-jvm) with Nashorn.
>>>>>
>>>>> Roughly, the way it works (and I'm sure you're already familiar 
>>>>> with this technique) is it takes the JavaScript module and wraps 
>>>>> it in a Function object:
>>>>>
>>>>> var body = readScriptAsText();
>>>>> var args   = ['exports', 'module', 'require', '__filename', 
>>>>> '__dirname'];
>>>>> var func = new Function(args, body);
>>>>> func.apply(module, [module.exports, module, module.require, 
>>>>> module.filename, dir]); // Execute it - this works fine
>>>>>
>>>>> Now let's say the actual module (foomodule.js) we are loading 
>>>>> contains this:
>>>>>
>>>>> module.exports = function() {
>>>>>     var num = 234;
>>>>>     num.substr(1, 1); // Will throw TypeError here
>>>>> }
>>>>>
>>>>> I.e. it simply exports a function, which will throw a TypeError 
>>>>> when it's executed.
>>>>>
>>>>> When the exported function is executed it does indeed throw a 
>>>>> TypeError:
>>>>>
>>>>> var f = require("foomodule");
>>>>>
>>>>> f(); // Throws TypeError
>>>>>
>>>>> Unfortunately the fileName field of the TypeError is set to 
>>>>> "<function>" not to "foomodule.js", which is unfriendly for the user.
>>>>>
>>>>> This is understandable as the Function object which wraps the 
>>>>> module doesn't know about "foomodule.js".
>>>>>
>>>>> So.. my question is.. how do I tell the Function object that the 
>>>>> "filename" it should use when exceptions are thrown from it is 
>>>>> "foomodule.js"?
>>>>>
>>>>> I have tried the following and none work:
>>>>>
>>>>> var func = new Function(args, body);
>>>>> func.name = "foomodule.js";
>>>>> func.fileName = "foomodule.js";
>>>>> func.displayName = "foomodule.js";
>>>>>
>>>>> Any insights would be greatly appreciated.
>>>>>
>>>>>
>>>>>
>>>>>
>>>>
>>>
>>
>