Number fields in app configurations silently default to 0 if no value is input by the user

[shiruken]

Info

App configuration fields of type number only allow inputting numeric values. However, if the user clears the field and clicks submit, Devvit silently sets the value to 0 without any indication. The user would not see this change unless they refresh the settings page.

For the app developer, this is impossible to handle when 0 is a valid value for the field. This breaks using input validation to make a field required since event.value = 0.

Potential Fix

settings.get() and settings.getAll() suggest that undefined is a valid value for settings:

devvit/packages/public-api/src/types/settings.ts

Line 58 in 8ca9b5e

get<T = string | string[] | boolean | number>(name: string): Promise<T | undefined>;

devvit/packages/public-api/src/types/settings.ts

Line 46 in 8ca9b5e

export type SettingsValues = { [key: string]: string | string[] | boolean | number | undefined };

Devvit should set fields of type number equal to undefined when the submitted field was empty. This will allow for using input validation to require the field when 0 is a valid value for the field.