Use patch.patch() when checking for patch availability.
The test is closer to what we want to know. It also makes sense when you deal with patched versions of patch() as most people do under win32.
Mercurial's documentation is currently kept in ASCIIDOC format, which
is a simple plain text format that's easy to read and edit. It's also
convertible to a variety of other formats including standard UNIX man
page format and HTML.
To do this, you'll need to install ASCIIDOC:
http://www.methods.co.nz/asciidoc/
To generate the man page:
asciidoc -d manpage -b docbook hg.1.txt
xmlto man hg.1.xml
To display:
groff -mandoc -Tascii hg.1 | more
To create the html page (without stylesheets):
asciidoc -b html hg.1.txt