MAS Videos - Displaying first name and last name fields on registration page.

functions.php

/**
 * Displaying first name and last name fields on 
 * MAS Video's registration page.
 */
function masvideos_customize_register_form() {
    $fields = array(
        'first_name'    => __('First name', 'masvideos'),
        'last_name'     => __('Last name', 'masvideos')
    );
    foreach( $fields as $k => $v ): ?>
        <p class="form-row form-row-wide">
        <label for="<?php echo $k; ?>"><?php echo $v; ?> <span class="required">*</span></label>
        <input type="text" class="input-text" name="<?php echo $k; ?>" id="<?php echo $k; ?>" value="<?php 
                if ( ! empty( $_POST[$k] ) ) echo esc_attr( $_POST[$k] ); ?>" />
        </p>
    <?php 
    endforeach;
}
add_action( 'masvideos_register_form_start', 'masvideos_customize_register_form' );

/**
 * Validate the extra register fields.
 */
function masvideos_customize_registration_errors( $validation_error, $username, $password, $email )
{
    if( !isset($_POST['first_name']) || empty($_POST['first_name']) ){
        $validation_error->add('error', 'Please enter your First name');
    }
    elseif( !isset($_POST['last_name']) || empty($_POST['last_name']) ){
        $validation_error->add('error', 'Please enter your Last name');
    }
    return $validation_error;
}
add_filter( 'masvideos_process_registration_errors', 'masvideos_customize_registration_errors', 10, 4 );

/**
 * Save the extra register fields.
 */
function masvideos_customize_new_user_data( $data ) {
    /**
     * WordPress will automatically insert this information's into database, 
     * we just need to include it here
    **/
    $data['first_name'] = masvideos_clean( $_POST['first_name'] );
    $data['last_name'] = masvideos_clean( $_POST['last_name'] );

    return $data;
}
add_filter( 'masvideos_new_user_data', 'masvideos_customize_new_user_data' );