notify: permit suppression of merge changeset notification

In some environments merges occur regularly but with no conflicts, and
committers find merge notifications more of a bother than a help.

By setting merge=False in [notify], merge notifications are suppressed.
This works both for incoming and for changegroup hooks.

hgext/notify.py

@@ -1,298 +1,316 b''
 # notify.py - email notifications for mercurial
 #
 # Copyright 2006 Vadim Gelfer <[e-mail]>
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2, incorporated herein by reference.
 
 '''hooks for sending email notifications at commit/push time
 
 Subscriptions can be managed through a hgrc file. Default mode is to
 print messages to stdout, for testing and configuring.
 
 To use, configure the notify extension and enable it in hgrc like
 this::
 
   [extensions]
   hgext.notify =
 
   [hooks]
   # one email for each incoming changeset
   incoming.notify = python:hgext.notify.hook
   # batch emails when many changesets incoming at one time
   changegroup.notify = python:hgext.notify.hook
 
   [notify]
   # config items go here
 
 Required configuration items::
 
   config = /path/to/file # file containing subscriptions
 
 Optional configuration items::
 
   test = True            # print messages to stdout for testing
   strip = 3              # number of slashes to strip for url paths
   domain = example.com   # domain to use if committer missing domain
   style = ...            # style file to use when formatting email
   template = ...         # template to use when formatting email
   incoming = ...         # template to use when run as incoming hook
   changegroup = ...      # template when run as changegroup hook
   maxdiff = 300          # max lines of diffs to include (0=none, -1=all)
   maxsubject = 67        # truncate subject line longer than this
   diffstat = True        # add a diffstat before the diff content
   sources = serve        # notify if source of incoming changes in this list
                          # (serve == ssh or http, push, pull, bundle)
+  merge = False          # send notification for merges (default True)
   [email]
   from = [e-mail]   # email address to send as if none given
   [web]
   baseurl = http://hgserver/... # root of hg web site for browsing commits
 
 The notify config file has same format as a regular hgrc file. It has
 two sections so you can express subscriptions in whatever way is
 handier for you.
 
 ::
 
   [usersubs]
   # key is subscriber email, value is ","-separated list of glob patterns
   user@host = pattern
 
   [reposubs]
   # key is glob pattern, value is ","-separated list of subscriber emails
   pattern = user@host
 
 Glob patterns are matched against path to repository root.
 
 If you like, you can put notify config file in repository that users
 can push changes to, they can manage their own subscriptions.
 '''
 
 from mercurial.i18n import _
 from mercurial import patch, cmdutil, templater, util, mail
 import email.Parser, email.Errors, fnmatch, socket, time
 
 # template for single changeset can include email headers.
 single_template = '''
 Subject: changeset in {webroot}: {desc|firstline|strip}
 From: {author}
 
 changeset {node|short} in {root}
 details: {baseurl}{webroot}?cmd=changeset;node={node|short}
 description:
 \t{desc|tabindent|strip}
 '''.lstrip()
 
 # template for multiple changesets should not contain email headers,
 # because only first set of headers will be used and result will look
 # strange.
 multiple_template = '''
 changeset {node|short} in {root}
 details: {baseurl}{webroot}?cmd=changeset;node={node|short}
 summary: {desc|firstline}
 '''
 
 deftemplates = {
     'changegroup': multiple_template,
 }
 
 class notifier(object):
     '''email notification class.'''
 
     def __init__(self, ui, repo, hooktype):
         self.ui = ui
         cfg = self.ui.config('notify', 'config')
         if cfg:
             self.ui.readconfig(cfg, sections=['usersubs', 'reposubs'])
         self.repo = repo
         self.stripcount = int(self.ui.config('notify', 'strip', 0))
         self.root = self.strip(self.repo.root)
         self.domain = self.ui.config('notify', 'domain')
         self.test = self.ui.configbool('notify', 'test', True)
         self.charsets = mail._charsets(self.ui)
         self.subs = self.subscribers()
+        self.merge = self.ui.configbool('notify', 'merge', True)
 
         mapfile = self.ui.config('notify', 'style')
         template = (self.ui.config('notify', hooktype) or
                     self.ui.config('notify', 'template'))
         self.t = cmdutil.changeset_templater(self.ui, self.repo,
                                              False, None, mapfile, False)
         if not mapfile and not template:
             template = deftemplates.get(hooktype) or single_template
         if template:
             template = templater.parsestring(template, quoted=False)
             self.t.use_template(template)
 
     def strip(self, path):
         '''strip leading slashes from local path, turn into web-safe path.'''
 
         path = util.pconvert(path)
         count = self.stripcount
         while count > 0:
             c = path.find('/')
             if c == -1:
                 break
             path = path[c+1:]
             count -= 1
         return path
 
     def fixmail(self, addr):
         '''try to clean up email addresses.'''
 
         addr = util.email(addr.strip())
         if self.domain:
             a = addr.find('@localhost')
             if a != -1:
                 addr = addr[:a]
             if '@' not in addr:
                 return addr + '@' + self.domain
         return addr
 
     def subscribers(self):
         '''return list of email addresses of subscribers to this repo.'''
         subs = set()
         for user, pats in self.ui.configitems('usersubs'):
             for pat in pats.split(','):
                 if fnmatch.fnmatch(self.repo.root, pat.strip()):
                     subs.add(self.fixmail(user))
         for pat, users in self.ui.configitems('reposubs'):
             if fnmatch.fnmatch(self.repo.root, pat):
                 for user in users.split(','):
                     subs.add(self.fixmail(user))
         return [mail.addressencode(self.ui, s, self.charsets, self.test)
                 for s in sorted(subs)]
 
     def url(self, path=None):
         return self.ui.config('web', 'baseurl') + (path or self.root)
 
     def node(self, ctx, **props):
-        '''format one changeset.'''
+        '''format one changeset, unless it is a suppressed merge.'''
+        if not self.merge and len(ctx.parents()) > 1:
+            return False
         self.t.show(ctx, changes=ctx.changeset(),
                     baseurl=self.ui.config('web', 'baseurl'),
                     root=self.repo.root, webroot=self.root, **props)
+        return True
 
     def skipsource(self, source):
         '''true if incoming changes from this source should be skipped.'''
         ok_sources = self.ui.config('notify', 'sources', 'serve').split()
         return source not in ok_sources
 
     def send(self, ctx, count, data):
         '''send message.'''
 
         p = email.Parser.Parser()
         try:
             msg = p.parsestr(data)
         except email.Errors.MessageParseError, inst:
             raise util.Abort(inst)
 
         # store sender and subject
         sender, subject = msg['From'], msg['Subject']
         del msg['From'], msg['Subject']
 
         if not msg.is_multipart():
             # create fresh mime message from scratch
             # (multipart templates must take care of this themselves)
             headers = msg.items()
             payload = msg.get_payload()
             # for notification prefer readability over data precision
             msg = mail.mimeencode(self.ui, payload, self.charsets, self.test)
             # reinstate custom headers
             for k, v in headers:
                 msg[k] = v
 
         msg['Date'] = util.datestr(format="%a, %d %b %Y %H:%M:%S %1%2")
 
         # try to make subject line exist and be useful
         if not subject:
             if count > 1:
                 subject = _('%s: %d new changesets') % (self.root, count)
             else:
                 s = ctx.description().lstrip().split('\n', 1)[0].rstrip()
                 subject = '%s: %s' % (self.root, s)
         maxsubject = int(self.ui.config('notify', 'maxsubject', 67))
         if maxsubject and len(subject) > maxsubject:
             subject = subject[:maxsubject-3] + '...'
         msg['Subject'] = mail.headencode(self.ui, subject,
                                          self.charsets, self.test)
 
         # try to make message have proper sender
         if not sender:
             sender = self.ui.config('email', 'from') or self.ui.username()
         if '@' not in sender or '@localhost' in sender:
             sender = self.fixmail(sender)
         msg['From'] = mail.addressencode(self.ui, sender,
                                          self.charsets, self.test)
 
         msg['X-Hg-Notification'] = 'changeset %s' % ctx
         if not msg['Message-Id']:
             msg['Message-Id'] = ('<hg.%s.%s.%s@%s>' %
                                  (ctx, int(time.time()),
                                   hash(self.repo.root), socket.getfqdn()))
         msg['To'] = ', '.join(self.subs)
 
         msgtext = msg.as_string()
         if self.test:
             self.ui.write(msgtext)
             if not msgtext.endswith('\n'):
                 self.ui.write('\n')
         else:
             self.ui.status(_('notify: sending %d subscribers %d changes\n') %
                            (len(self.subs), count))
             mail.sendmail(self.ui, util.email(msg['From']),
                           self.subs, msgtext)
 
     def diff(self, ctx, ref=None):
 
         maxdiff = int(self.ui.config('notify', 'maxdiff', 300))
         prev = ctx.parents()[0].node()
         ref = ref and ref.node() or ctx.node()
         chunks = patch.diff(self.repo, prev, ref, opts=patch.diffopts(self.ui))
         difflines = ''.join(chunks).splitlines()
 
         if self.ui.configbool('notify', 'diffstat', True):
             s = patch.diffstat(difflines)
             # s may be nil, don't include the header if it is
             if s:
                 self.ui.write('\ndiffstat:\n\n%s' % s)
 
         if maxdiff == 0:
             return
         elif maxdiff > 0 and len(difflines) > maxdiff:
             msg = _('\ndiffs (truncated from %d to %d lines):\n\n')
             self.ui.write(msg % (len(difflines), maxdiff))
             difflines = difflines[:maxdiff]
         elif difflines:
             self.ui.write(_('\ndiffs (%d lines):\n\n') % len(difflines))
 
         self.ui.write("\n".join(difflines))
 
 def hook(ui, repo, hooktype, node=None, source=None, **kwargs):
     '''send email notifications to interested subscribers.
 
     if used as changegroup hook, send one email for all changesets in
     changegroup. else send one email per changeset.'''
 
     n = notifier(ui, repo, hooktype)
     ctx = repo[node]
 
     if not n.subs:
         ui.debug('notify: no subscribers to repository %s\n' % n.root)
         return
     if n.skipsource(source):
         ui.debug('notify: changes have source "%s" - skipping\n' % source)
         return
 
     ui.pushbuffer()
+    data = ''
+    count = 0
     if hooktype == 'changegroup':
         start, end = ctx.rev(), len(repo)
-        count = end - start
         for rev in xrange(start, end):
-            n.node(repo[rev])
+            if n.node(repo[rev]):
+                count += 1
+            else:
+                data += ui.popbuffer()
+                ui.note(_('notify: suppressing notification for merge %d:%s\n') %
+                        (rev, repo[rev].hex()[:12]))
+                ui.pushbuffer()
+        if count:
         n.diff(ctx, repo['tip'])
     else:
-        count = 1
-        n.node(ctx)
+        if not n.node(ctx):
+            ui.popbuffer()
+            ui.note(_('notify: suppressing notification for merge %d:%s\n') %
+                    (ctx.rev(), ctx.hex()[:12]))
+            return
+        count += 1
         n.diff(ctx)
 
-    data = ui.popbuffer()
+    data += ui.popbuffer()
+    if count:
     n.send(ctx, count, data)