Field components should discard non-parsable programmatically set values / constraints, showing a warning

[vursen]

Motivation

Currently, the way field components handle non-parsable values or constraints is not consistent and user-friendly.

• integer-field resets values that don't match the integer pattern, showing a warning.
• date-picker resets values that cannot be parsed to the default empty string, not showing any warning though.
• ...

The same goes for constraints:

• integer-field just ignores non-integer min and max, not showing any warning.
• date-picker just ignores non-parsable min and max, not showing any warning.
• ...

Solution

When setting a non-parsable value or constraint, the component should (a) discard it to the default one and (b) show a warning like:

<vaadin-date-picker> The `min` property must be a valid date but `{...}` was provided, so the property was reset to `{...}`.

Components

• [ ] date-picker
• [ ] time-picker
• [ ] date-time-picker
• [ ] integer-field
• [ ] number-field

[knoobie]

That feels like the opposite of https://github.com/vaadin/flow-components/issues/2466

[vursen]

That feels like the opposite of https://github.com/vaadin/flow-components/issues/2466

I might be wrong but the ticket you mentioned proposes a fallback parser in case the user enters something not typical into the input element. This ticket is however about setting the value property which is always expected to follow a certain format (in the case of the listed components). Like, for example, the date-picker's value property only allows ISO date strings.

[knoobie]

You are right! I had the feeling the value was the same as user entering value - don't mind me :)