--- a/plugin.py	Wed Nov 21 00:22:32 2018 +0800
+++ b/plugin.py	Wed Nov 21 01:27:49 2018 +0800
@@ -32,6 +32,7 @@
 from supybot.commands import *
 
 import os
+import subprocess
 
 import urllib
 import logging
@@ -109,11 +110,12 @@
         self.path = path
 
     def run(self, args):
-        fd = os.popen('HGPLAIN=1 %s %s' % (self.path, args))
-        out = fd.read()
-        fd.close()
-
-        return out
+        with open(os.devnull) as null:
+            p = subprocess.Popen([self.path] + args, stdout=subprocess.PIPE,
+                                 stderr=subprocess.PIPE, stdin=null,
+                                 env={'HGPLAIN': '1', 'HGENCODING': 'UTF-8'})
+        out, err = p.communicate()
+        return (out.decode('utf-8'), err.decode('utf-8'))
 
 class Mercurial(callbacks.Plugin):
     """Add the help for "@plugin help Mercurial" here
@@ -142,24 +144,26 @@
             elif len(out) > 1:
                 out[1] = ircutils.bold(out[1])
             out = out[:10]
-
-            if out and out[0].startswith('Mercurial Distributed SCM'):
-                out = ['"%s": unknown command' % cmd]
             return out
 
-        out = self.hg.run('help ' + cmd)
-        irc.replies(fmt(out))
+        out, err = self.hg.run(['help', cmd])
+        if err:
+            irc.reply(err.splitlines()[0])
+        else:
+            irc.replies(fmt(out))
 
     hghelp = wrap(hghelp, ['text'])
 
-    def changelog(self, repo, rev):
+    def changelog(self, irc, repo, rev):
         tmpl = '{rev}:{node|short}\n{date|age}\n{author|person}\n{files}\n{desc}'
-        cmd = "-R %s log -v --limit 1 --template '%s' -r %s" \
-              % (repo, tmpl, rev)
-        out = self.hg.run(cmd)
+        out, err = self.hg.run([
+            '-R', repo, 'log', '-r', rev, '-l', '1', '--template', tmpl, '-v'
+        ])
 
+        if err:
+            return irc.reply(err.splitlines()[0])
         if not out:
-            return ['No result found.']
+            return irc.reply('no changesets found')
 
         lines = [x for x in out.strip().splitlines() if x]
         node, date, user, files = lines[:4]
@@ -169,20 +173,18 @@
 
         lines = ['%s %s %s' % (node, user, date)] + lines
 
-        baseurl = self.hg.run("-R %s paths default" % repo)
+        baseurl, err = self.hg.run(['-R', repo, 'paths', 'default'])
         url = "%s/rev/%s" % (baseurl.strip("\n/"), rev)
-        return lines[:2] + [url]
+        irc.replies(lines[:2] + [url])
 
     def crew(self, irc, msg, args, rev):
         "gets the changelog message for the given revision of the crew repository"
-        cl = self.changelog('/home/brendan/hg/mirror/mercurial/crew', rev)
-        irc.replies(cl)
+        self.changelog(irc, '/home/brendan/hg/mirror/mercurial/crew', rev)
     crew = wrap(crew, ['revision'])
 
     def main(self, irc, msg, args, rev):
         "gets the changelog message for the given revision of the crew repository"
-        cl = self.changelog('/home/hg/repos/hg', rev)
-        irc.replies(cl)
+        self.changelog(irc, '/home/hg/repos/hg', rev)
     main = wrap(main, ['revision'])
 
     def bts(self, irc, msg, args, issue):
@@ -208,11 +210,11 @@
 
     def glossary(self, irc, msg, args, term):
         """usage: glossary <term>"""
-        raw = self.hg.run('help glossary').splitlines()
+        raw, err = self.hg.run(['help', 'glossary'])
         found = False
         done = False
         answer = []
-        for line in raw:
+        for line in raw.splitlines():
             if not found and line.lower().startswith('    ' + term.lower()):
                 found = True
             elif found and not (line.startswith('        ') or not line):
@@ -222,9 +224,10 @@
             if found and not done and line:
                 answer.append(line)
 
-        if not answer:
-            answer = ['', 'no match found']
-        irc.reply(' '.join(answer[1:]))
+        if answer:
+            irc.replies(answer[1:], joiner=' ')
+        else:
+            irc.reply('no match found')
     glossary = wrap(glossary, ['text'])
 
 Class = Mercurial