Handle error for values of invalid data types in DateField

[qbantek]

This PR proposes changes to handle the scenario when the DateField value does not match the type criteria to be handled as a Date.

Current behavior causes an error when trying to execute date.toLocaleString() on an undefined date value.

DateField.tsx:99 Uncaught TypeError: Cannot read properties of undefined (reading 'toLocaleString')
    at DateFieldImpl (DateField.tsx:99:20)
    at renderWithHooks (react-dom.development.js:16305:18)
    at updateFunctionComponent (react-dom.development.js:19588:20)
    at updateSimpleMemoComponent (react-dom.development.js:19425:10)
    at updateMemoComponent (react-dom.development.js:19284:14)
    at beginWork (react-dom.development.js:21673:16)
    at HTMLUnknownElement.callCallback2 (react-dom.development.js:4164:14)
    at Object.invokeGuardedCallbackDev (react-dom.development.js:4213:16)
    at invokeGuardedCallback (react-dom.development.js:4277:31)
    at beginWork$1 (react-dom.development.js:27451:7)

[fzaninotto]

Thanks for the PR.

This PR raises an important question: when the value is invalid, should we display the empty text, or a new "invalid value" message? Because the problem also occurs in other fields, and react-admin needs to be consistent.

@djhi @slax57 any feedback on this question?

[fzaninotto]

I doin't understand why you extracted to a function just to call it afterwards.

[qbantek]

I did it to encapsulate the logic for validating whether the value can represent a Date or not. Probably a matter of style and personal preference, I can change it to inline code obviously.

[fzaninotto]

yes, please inline this code

[fzaninotto]

Please keep the value == null test instead.

[qbantek]

Not sure if I understood this request properly: Are you asking to have BOTH value == null and typeof date === 'undefined' or to get rid if the undefined criteria?

The way I see it the null check is handled before (in parsedDate function) and the undefined check is needed to avoid the error, kinda the whole point of this PR. Please correct me if I am wrong.

[fzaninotto]

No you're right, the check is already made in parsedDate, you can keep your code as is for this part.

[slax57]

@fzaninotto That's a good question indeed. I guess it can't hurt to introduce a new "invalid value" message, which will help both the developer (to see that there is an issue with the data) and the user (to avoid having a runtime error and a blank value).

[fzaninotto]

In all the react-admin fields, only two render a different output in case of error: ReferenceField and ReferenceManyCount.

I think it's a good thing to show to the user that the value is invalid, so I'd recommend we do the same for invalid dates in DateField. In that case, the field could render the same ErrorIcon as ReferenceField.