topic: make ranges work in revset relations like 'foo#topic[1:2]'
Since #topic is very similar to #generations, we reuse the function directly.
Few tests because #generations is already tested in core.
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