Function findLensScriptError

Returns the LensScriptError behind a Lens failure, or undefined if none was created. That happens when the failure wasn't the Lens's script (for example, the Lens could not be downloaded or one of its assets could not be loaded), or when the script threw something other than an Error — see LensScriptError.

A Lens script can throw at two moments, and this works the same for both:

import { findLensScriptError } from '@snap/camera-kit'

// 1. While the Lens is being applied: applyLens rejects with a LensError.
try {
  await cameraKitSession.applyLens(lens)
} catch (error) {
  const scriptError = findLensScriptError(error)
  if (scriptError) console.log(`Lens ${lens.name} failed to start:\n${scriptError.stack}`)
}

// 2. While the Lens is rendering: Camera Kit removes the Lens and emits a LensExecutionError.
cameraKitSession.events.addEventListener('error', ({ detail }) => {
  const scriptError = findLensScriptError(detail.error)
  if (scriptError) {
    console.log(`Lens ${detail.lens.name} has a script error:\n${scriptError.stack}`)
  } else {
    console.log(`Lens ${detail.lens.name} encountered an error and was removed.`)
  }
})
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The stack looks like this:

LensScriptError: TypeError: cannot read property 'text' of undefined
    at onTap (Scripts/TapHandler.js:18:22)
    at apply (native)
    at <anonymous> (Scripts/TapHandler.js:9:5)
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