Suppress errors generated by specified WordPress plugins to make developing with debug mode on less painful.

local-error-handler.php

<?php
/**
 * Suppress errors generated by specified WordPress plugins.
 *
 * Include in the auto_prepend_file php.ini directive to ignore globally.
 *
 * @see http://plugins.trac.wordpress.org/browser/ostrichcize/tags/0.1/ostrichcize.php#L146
 *
 * @param string $errno The error number.
 * @param string $errstr The error message.
 * @param string $errfile Path to the file that caused the error.
 * @param int $errline Line number of the error.
 * @return bool True to success error reporting; false to use default error handler.
 */

function bc_custom_error_handler( $errno, $errstr, $errfile, $errline ) {
  $patterns = array(
    'plugins/dflip',
    'plugins/events-calendar-pro',
    'plugins/google-analytics-premium',
    'plugins/ninja-forms',
    'plugins/pojo-accessibility',
    'plugins/the-events-calendar',
    'plugins/the-events-calendar-filterbar',
  );

  foreach ( $patterns as $pattern ) {
    $pattern = str_replace( array( '/', '\\' ), DIRECTORY_SEPARATOR, $pattern );

    if ( false !== strpos( $errstr, $pattern ) || false !== strpos( $errfile, $pattern ) ) {
      return true;
    }
  }

  return false;
}
set_error_handler( 'bc_custom_error_handler' );