Link: http://example.com/.
With an ampersand: http://example.com/?foo=1&bar=2
An example https link: https://www.example.com without a final slash
Brackets appearing (without the presence of a link)
Inside the link description, can we have emphasised, or strong text?
A test of context-sensitive whitespace swallowing: (there should be no whitespace before the full-stop).
A test of unterminated paren_descriptors: http://www.example.com ((Technically should be invalid?)
Link followed by confusing emoticon http://www.example.com (-:
Blockquoted: http://example.com/
Auto-links should not occur here: <http://example.com/>
or here: <http://example.com/>