Enhancement: Add a wrong password message on password protected posts

[henry.wright]

If a post is password protected, the user is shown a form where they can enter a password to gain access. If a wrong password is given, there's no helpful message shown to the user. The page is simply reloaded.

Something like "Wrong password. Please try again." would be helpful here.

[Jonnyauk]

Adds error message if post password is incorrect. Adds new function get_the_password_form_wrong_password() and new filter 'the_password_form_wrong_password'

[Jonnyauk]

Agreed - users should definitely get feedback if the post password is inputted incorrectly - see 37332-01.patch for a suggested solution to this.

[Jonnyauk]

Updated patch file in correct format (trunk dev version) - Adds error message if post password is incorrect. Adds new function get_the_password_form_wrong_password() and new filter 'the_password_form_wrong_password'

[kreppar]

Hi, I was checking if there were any related tickets before creating a new one and I came across this.

I implemented a solution very similar to the one proposed by @Jonnyauk with the difference that I add a conditional

if ( wp_get_raw_referer() !== get_the_permalink() ) {
	return $form;
}

to check where the request originates and avoid that if the password is wrong, it is shown in all post them with password protection.

@SergeyBiryukov is there a will to push this old request? In that case I can send a PR.

Thanks

Adds filters and markup to handle showing an "incorrect post password" message whenever using the post password system and the user enters a wrong password.

There is a current edge case where the "incorrect post password" message will show if:

• The user visits the page and enters and incorrect post password.
• "incorrect post password" message shown as expected.
• The user then clicks a navigation link to the same page.
• "incorrect post password" message shown again because the referrer was the current page, even though the form wasn't submitted.

Trac ticket: https://core.trac.wordpress.org/ticket/37332