Fix MaskedInput selection replace with invalid value

[JonathanPlasse]

Please review the following checklist.

• Fix MaskedInput ValueError Value does not match template #5493

This PR implements the MaskedInput.replace() method by using the already existing MaskedInput.insert_text_at_cursor() which replace the characters following the cursor position.

• Docstrings on all new or modified functions / classes
• Updated documentation
• Updated CHANGELOG.md (where appropriate)

[TomJGooding]

TheMaskedInput will select all text on focus by default, but this isn't obvious until you add the highlighting.

Wouldn't this PR only replace a single character, rather than the whole selection as you would expect?

[JonathanPlasse]

You are right

[JonathanPlasse]

Wouldn't this PR only replace a single character, rather than the whole selection as you would expect?

Fixed

[TomJGooding]

Unfortunately, I think fixing the MaskedInput to handle text selection is going to be more complicated.

For example, try running the credit card example in the docs with the changes in this PR. After entering some numbers to complete the input, try selecting some text using the mouse (it might help adding the highlighting) then enter a number. This will crash if the selection included a separator as the value does not match the template.

[JonathanPlasse]

This is now fixed.
The replace now behave like this:

• if the replace text is the same length as the selection (without separator), it replace exactly the selection
• if the replace text is greater, the replace text will be cut to fit within the selection
• if the replace text is lesser, the remaining selection text will be deleted
• if the selection starts on a separator, the replace text start after it