help: don't crash in keyword search if an extension fails to provide docs
Not all external extensions provide docs; if you use such an extension, you
will experience a crash if you use "hg help --keyword <word>", and <word>
happens to match the extension name.
--- a/mercurial/help.py Fri Jan 29 14:35:34 2016 +0000
+++ b/mercurial/help.py Wed Feb 10 01:48:58 2016 -0800
@@ -149,6 +149,8 @@
for name, docs in itertools.chain(
extensions.enabled(False).iteritems(),
extensions.disabled().iteritems()):
+ if not docs:
+ continue
mod = extensions.load(ui, name, '')
name = name.rpartition('.')[-1]
if lowercontains(name) or lowercontains(docs):