Text input doesn't allow to delete characters if length is greater than maxlength

[teapotd]

Servo doesn't allow to delete a character from text input that contains value longer than its maxlength. Other browsers allow it and some WPT tests depend on this behavior (e.g. html/semantics/forms/constraints/tooLong-input-text-delete-manual.html).

Example:
./mach run -d 'data:text/html,<input value="123456" maxlength="3">'
Try to use backspace in this field.

[jdm]

Looks like this case is explicitly called out in the code:

servo/components/script/textinput.rs

Lines 450 to 457 in 1e0f2e5

	let allowed_to_insert_count = if let Some(max_length) = self.max_length {
	let len_after_selection_replaced =
	self.utf16_len().saturating_sub(self.selection_utf16_len());
	if len_after_selection_replaced >= max_length {
	// If, after deleting the selection, the len is still greater than the max
	// length, then don't delete/insert anything
	return;
	}

We should definitely ignore any insertions that are beyond the max length, but I think we should be allowing deletions.

[teapotd]

@highfive assign me

[highfive]

Hey @teapotd! Thanks for your interest in working on this issue. It's now assigned to you!