packaging: require mercurial >= 4.5
Otherwise building the doc package fails with:
(third party extension evolve requires version 4.5 or newer of Mercurial; disabling)
Exception occurred:
File "/usr/lib/python2.7/dist-packages/mercurial/help.py", line 624, in help_
raise error.Abort(msg, hint=hint)
Abort: no such help topic: evolve
import hghave
@hghave.check("docgraph-ext", "Extension to generate graph from repository")
def docgraph():
try:
import hgext.docgraph
hgext.docgraph.cmdtable # trigger import
except ImportError:
try:
import hgext3rd.docgraph
hgext3rd.docgraph.cmdtable # trigger import
except ImportError:
return False
return True