showdownjs/test/functional/makehtml/cases/features/ghMentions.html

<p>hello <a href="https://github.com/tivie">@tivie</a> how are you?</p>
<p>this email foo@gmail.com is not parsed</p>
<p>this @mentions is not parsed</p>
<p><a href="https://github.com/john.doe">@john.doe</a></p>
<p><a href="https://github.com/john-doe">@john-doe</a></p>
<p><a href="https://github.com/john_doe">@john_doe</a></p>
<p>@.johndoe</p>
<p>@_johndoe</p>
<p>@-johndoe</p>
<p><a href="https://github.com/johndoe">@johndoe</a>.</p>
<p><a href="https://github.com/johndoe">@johndoe</a>-</p>
<p><a href="https://github.com/johndoe">@johndoe</a>_</p>