[PLAT-12625] Create new app start span wrapper

[gingerbenw]

Goal

Provide an alternative method to instrument app start spans aside from setWrapperComponentProvider

Design

Using a higher order component (HOC) will prevent the app from re-rendering when root props are updated from the native side

Changeset

• Expose new withInstrumentedAppStarts wrapper method from the performance client
• This PR also includes an alpha release for testing purposes

Testing

• Add new end to end test to validate spans are still created using the new method
• Manual testing that the root app does not re-render when properties update from native iOS code

[github-actions[bot]]

Browser bundle size

NPM build

	Package
Before	196.14 kB
After	196.19 kB
±	+48 bytes ⚠️

CDN build

	Unminified	Minfied	Minified + gzipped
Before	98.89 kB	36.61 kB	11.07 kB
After	98.89 kB	36.62 kB	11.07 kB
±	+8 bytes ⚠️	+8 bytes ⚠️	+7 bytes ⚠️

Code coverage

Ok	File (✨=New File)	Lines	Branches	Functions	Statements
🔴	✨ /home/runner/work/bugsnag-js-performance/bugsnag-js-performance/packages/platforms/react-native/lib/create-app-start-span.ts	100% (+100%)	0% (+0%)	100% (+100%)	87.5% (+87.5%)
🔴	✨ /home/runner/work/bugsnag-js-performance/bugsnag-js-performance/packages/platforms/react-native/lib/use-end-span-on-mount.ts	40% (+40%)	0% (+0%)	0% (+0%)	50% (+50%)

Total:

Lines	Branches	Functions	Statements
87.74%(-0.18%)	78.82%(-0.21%)	88.42%(-0.77%)	85.81%(-0.2%)

Generated against 2d964fc25036c3255f511d05b97b26d81ceb20ea on 4 September 2024 at 16:09:59 UTC

[yousif-bugsnag]

generally looks good to me - but I wonder if we should have some mechanism to prevent multiple app start spans from being created?

[gingerbenw]

I wonder if we should have some mechanism to prevent multiple app start spans from being created?

as in, if someone were to use the wrapper and the autoInstrumentAppStarts config option?

[yousif-bugsnag]

as in, if someone were to use the wrapper and the autoInstrumentAppStarts config option?

Yeah - perhaps that's something we just need to document clearly, but seems like it could happen fairly easily because that config option is true by default.

[yousif-bugsnag]

There's also nothing to stop someone wrapping multiple components using withInstrumentedAppStarts - they may even want to, for example an app that loads a login screen or goes straight to the main app screen depending on whether the user is authenticated might want to end the app start on whichever component is loaded first. But that could probably be a separate PR/future enhancement...

[gingerbenw]

@yousif-bugsnag added a simple check that only allows for a single app start span - create as many wrappers as you like 👍🏻