Breaking issue out from #1914694: Errors appearing in testbot Error logs..
This code from TermTest.php:
<?php
// Check that the term edit page does not try to interpret additional path
// components as arguments for taxonomy_term_form().
$this->drupalGet('taxonomy/term/'. $term->tid . '/edit/'. $this->randomName());
?>
Causes the following in testbot logs:
Uncaught PHP Exception InvalidArgumentException: "Missing 'form: eixEYdYX' for entity 'taxonomy_term'" at /var/lib/drupaltestbot/sites/default/files/checkout/core/lib/Drupal/Core/Entity/EntityManager.php line 115
As Berdir described at https://drupal.org/node/1914694#comment-7055418:
This results in that additional argument being passed to entity_get_form() and the exception. We need to fix that and add an assertion to actually register that it does in fact not work. Although it will stop working with the new router system.