When a native date input gets cleared manually by a user via the internal browser
UI, the element changes from invalid to valid, but no `input` event is emitted.
This commit introduces `InputValidityMonitor`, an injectable service that
intercepts these edge-case native status changes. The monitor dynamically
installs CSP-compliant styles appending specific animation keyframes for
`:valid` and `:invalid` pseudoclasses on native form controls. By attaching an
`animationstart` listener, Angular intercepts these changes immediately and
re-invokes the parser.
Fixes#67300
`<input type="number">` often does not provide the desired user experience when editing numbers in
a form. MDN even [describes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements/input/number#using_number_inputs)
how text inputs should be used in many cases instead, via `<input type="text" inputmode="numeric">`
or similar configurations. Previously, this did not work with Signal Forms without a custom input
component/directive.
This PR builds support for binding `number|null` models directly to `<input type="text">` native
controls via `[formField]`. When a model has a number or `null` value, signal forms will preserve
that status when the user makes edits/changes. Empty string values are converted to `null`, other
values are parsed as numbers, and a parse error is raised when a non-numeric value is entered.
Note that it's up to the UI developer to configure additional UI affordances such as setting an
appropriate `inputmode`, rejecting non-numeric keypresses, etc.
Fixes#66903Fixes#66157
Supports binding `null` to a `<input type=number>`.
- Binding in `null` clears the input
- Binding in `NaN` also clears the input
- When the user clears the input, the model is set to `null`
- The model is _never_ set to `NaN` based on user interaction. It is
either set to `null` if the user cleared the input, or is unchanged
and a parse error added if the user entered an invalid number like
"42e"
PR Close#66917
Integrates native inputs with the new parseErrors API so that they can
report parse errors when the user types an un-parsable value (e.g. "42e"
in a number field).
When a user types an un-parsable value, the model does not update. It
retains its previous value and a parse error is added for the control
that received the un-parsable value.
PR Close#66917
Pawel Kozlowski