Login with Email only

This simple Drupal module allows users to log in exclusively with their email address from the standard login form. It also changes the "Forgot your password" flow, by requiring to insert the email to recover the end-user password.

The difference between this module and the other ones is that you cannot login using your username with this module.

Setup:

Just enable the module.

Dependencies:

Core dependencies only.

Installation:

Install via /admin/modules
or
drush en login_onlyemail -y

Configuration:

There are no configuration options, however, you must disable this module if you are going to perform core integration tests using the drupalLogin() method.

Compatibility:

Note that other authentication modules, like LoginToboggan and Email Registration might be incompatible with this module.

Recommended Modules:

This module is based on the Login Email or Username module:
https://www.drupal.org/project/login_emailusername
Another more complete module called Mail Login achieves the same result:
https://www.drupal.org/project/mail_login