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I would like to be able to get the stack data (fileName and lineNumber) from an Error object in React Native.
If I run something like this: 

const err = new Error('Message');
console.log(err);

I get some helpful output in my console like this:

Message
* App.js:21:16 in componentDidMount
- node_modules\react-proxy\modules\createPrototypeProxy.js:61:45 in proxiedComponentDidMount
- node_modules\react-native\Libraries\Renderer\ReactNativeRenderer-dev.js:10627:12 in commitLifeCycles
- ... 23 more stack frames from framework internals

I would like to be able to send that stack data off elsewhere for logging and fixing, but I can't figure out how to access the data which shows the filename and the line where the error was generated.
How can I get that information?
As per the documentation Error - JavaScript MDN, if I try:

console.log(err.fileName)

or:

console.log(err.lineNumber)

I just get:

undefined

Which is confirmed by:

console.log(Object.keys(err));

resulting in:

Array []

Although, mysteriously:

console.log(err.message);

still returns:

Message

Related - if I enter:

console.log(err.toString())

I get:

Error: Message

Similarly, if I enter:

console.log('Comment', err);

I get as output:

Comment [Error: Message]

So while I can see the stack data is there, I don't seem to be able to access it or pass it somewhere else.

Sho Ya
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1 Answers1

-1

check out https://github.com/marchingband/expo-error-log. You'll need to register your own Error Handler callback. You can use an ErrorBoundary, or capture the errors in a number of other ways, some of which will capture all the JS errors, some of which will not.

Marchingband
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