SongTile crash

[zhammer]

https://sentry.io/zach-hammer/morning-cd-web-client/issues/853170016

[zhammer]

I think that essentially what's happening here is:

• I'm on the song submit page
• I click 'submit song'
• loading is set to true
  • therefore, showSubmitSong is set to false
  • https://github.com/zhammer/morning-cd/blob/bb452038bba4ef88a6532386b8f9fe3c11624b67/web_client/src/App.tsx#L86-L88
• SubmitSongPage begins fade out, but is still being rendered and depends on selectedSong having a value
  • hence the typecasting here
  • https://github.com/zhammer/morning-cd/blob/bb452038bba4ef88a6532386b8f9fe3c11624b67/web_client/src/App.tsx#L227-L232
• the server responds quickly, before the SubmitSongPage fadeout completes
• loading is set to false and selectedSong is set to null
  • https://github.com/zhammer/morning-cd/blob/bb452038bba4ef88a6532386b8f9fe3c11624b67/web_client/src/App.tsx#L187-L188
• since the SubmitSongPage is still being faded out, and is still rendering, it tries to use its song prop, which is null, and CRASH

[zhammer]

honestly for now i think i'll just set a delay on setting selectedSong to null, but this points to a bigger issue (that i'm surprised hasn't happened before) with the FadeInFadeOut

[zhammer]

i have a feeling that if the user is on the song submit form, and sunset happens, their page will crash as well

https://github.com/zhammer/morning-cd/blob/bb452038bba4ef88a6532386b8f9fe3c11624b67/web_client/src/App.tsx#L122-L127