Checks if current screen is Edit screen of a given list of post types.

is_edit_screen.php

<?php
/**
 * Return true if current screen is edit screen of a post type or list of post types.
 *
 * @param  string|array  $post_type Single or list of post types.
 * @return boolean
 */
function is_edit_screen( $post_types = array() ) {
  global $pagenow;
  if ( 'post.php' !== $pagenow ) {
    return false;
  }

  if ( ! is_array( $post_types ) ) {
    $post_types = array( $post_types );
  }

  if ( ! empty( $post_types ) && function_exists( 'get_current_screen' ) ) {
    if ( ! in_array( get_current_screen()->post_type, $post_types ) ) {
      return false;
    }
  }

  return true;
}