Template name for the user login block

Question

I have been trying to create a template to control the user login block given in Drupal 7. I've referred to the template suggestions documentation page and have tried block--user-login.tpl.php, block--user.tpl.php and am getting no love.
What is the template name for the user login block?.

Answer 1

Since I answered this in IRC, I'll rewrite the answer.

block--user--login.tpl.php

The easiest way to find all of the possibilities for naming template files is to put print_r($variables['theme_hook_suggestions']); at the end of your theme's template_preprocess_HOOK(). Doing so works great for block, node, page...