Fixing error output for non-error instance

[martinheidegger]

I received following error

TypeError: Cannot read property 'stack' of undefined
at WebSocket.window.onerror (/Users/m/Documents/datproject/sdk/node_modules/electron-stream/lib/preload.js:23:23)
at /Users/m/Documents/datproject/sdk/node_modules/electron-stream/lib/preload.js:23:23

Noticing that an unhandled websocket error event is also handled by the onerror handler and causes above error.

This PR should fix that error and give more information if other, non-traditional, errors occur.

As far as events are concerned: The target can give insight on where the error occured, however in my case it resulted in an error message like Unhandled error event at WebSocket {} which didn't tell me much, so I added a .toString(){} method on the websocket giving me a bit more information which was meant. Now it shows an error message like: Unhandled error event at WebSocket {} "[object WebSocket, url=ws://localhost:9001/]"

[juliangruber]

sorry for the late review, looks mostly gtm

[juliangruber]

why msg.taget twice here?

[martinheidegger]

The first time it is passed as object, the second time stringified, the reason for this is to easier identify an error once occurred. Depending on the environment the object visualization may help more or less than the toString() info.

[juliangruber]

Can you explain in which case stringifying the object helps?

This is in the browser:

const obj = { oh: 'hi' }
console.log(obj, String(obj))
// => {oh: "hi"} "[object Object]"

and this in node:

const obj = { oh: 'hi' }
console.log(obj, String(obj))
// => { oh: 'hi' } [object Object]

The console.error(obj) should be enough.

[juliangruber]

Do you know in which case this condition would happen?

[martinheidegger]

Tbh. no, i added it for "in case". Since it seems to be a possibility, from the argument pattern.

[juliangruber]

Could you please add a comment for this, as it wasn't obvious to me?

[martinheidegger]

@juliangruber Thank you for your review, I decided to rewrite this PR in 06e1ebb. I added comments and explanations to previous questions. Also now it will show clearly which "if" clause the error is in (Error, ErrorEvent, Event, other) and add the location as well as possible.