as you may all-ready know lastError is a global variable or property from chrome.runtime API used for determining if some error happened during the chrome API call execution.
It is defined only when there was an error, if the API call is OK it won't be defined. The error can be triggered from multiple reasons eg. bad API call due to missing or wrong parameter type, or it can be caused by user interaction, eg. the user rejects permission granting by pressing the "cancel" button.
Chrome has unified it's error handling by using this variable for error reporting across their API's instead of returning an error argument. Due to it's API's async nature Chrome makes an additional check that validates if chrome.runtime.lastError is checked/handled in the callback function from the extension code, if not it throws the famous Unchecked runtime.lastError
You can quickly get the error message by checking chrome.runtime.lastError.message and display it to the user, and all of this is great for most use cases, but I wouldn't write this question if that were my case.
So what happens when you need to implement some additional code logic based on the error result. Let's take launchWebAuthFlow for an example, for the sake of simplicity of the question, I will focus only on the two possible outcomes/errors that can happen:
User interaction required.thrown when API call with bad argument value is made, in this caseinteractive = falseThe user did not approve access.happens when the user closes the authentication window
So my question is, what will be the best way to implement additional logic based on the error?
Is a comparison of chrome.runtime.lastError.message the only way to do it, and if so, is it safe considering that the user browser language might be different than English.
What's your opinion, should Chromium dev team implement: chrome.runtime.lastError.code?