First find this line:
$form['path']['pathauto_perform_alias'] = array(
Then add:
'#value' => 1,
Source code viewer
'#type' => 'checkbox',
'#value' => 1,
'#title' => t('Automatic alias'),
'#default_value' => $node->pathauto_perform_alias,
'#description' => t('An alias will be generated for you. If you wish to create your own alias below, uncheck this option.'),
'#weight' => -1,
);Programming Language: PHP