On Thu, 2016-09-22 at 18:20 -0500, Kevin Bullock wrote:
> >
> > On Sep 22, 2016, at 13:21, Matt Mackall <m...@selenic.com> wrote:
> >
> > # HG changeset patch
> > # User Matt Mackall <m...@selenic.com>
> > # Date 1473794045 18000
> > # Tue Sep 13 14:14:05 2016 -0500
> > # Node ID 19bf2776dfe39befdc479253e1e7d030b41c08f9
> > # Parent 5271ae66615207f39cc41d78f4541bc6f8ca6ff6
> > extdata: add extdatasource reader
> >
> > This adds basic support for extdata, a way to add external data
> > sources for revsets and templates. An extdata data source is simply a
> > list of lines of the form:
> >
> > <revision identifier>[<space><freeform text>]\n
> >
> > An extdata source is configured thusly:
> >
> > [extdata]
> > name = <a url or path>
> >
> > urls of the form shell: are launch shell commands to generate data.
> >
> > diff -r 5271ae666152 -r 19bf2776dfe3 mercurial/scmutil.py
> > --- a/mercurial/scmutil.py Wed Sep 21 17:05:27 2016 -0400
> > +++ b/mercurial/scmutil.py Tue Sep 13 14:14:05 2016 -0500
> > @@ -29,6 +29,7 @@
> > phases,
> > revset,
> > similar,
> > + url,
> > util,
> > )
> >
> > @@ -1418,3 +1419,66 @@
> > return
> >
> > self._queue.put(fh, block=True, timeout=None)
> > +
> > +def extdatasources(repo):
> > + sources = set()
> > + for k, v in repo.ui.configitems("extdata"):
> > + sources.add(k)
> > + return sources
> > +
> > +def extdatasource(repo, source):
> > + """gather a map of rev -> value dict from the specified source
> > +
> > + A source spec is treated as a URL, with a special case shell: type
> > + for parsing the output from a shell command.
> > +
> > + The data is parsed as a series of newline-separated records where
> > + each record is a revision specifier optionally followed by a space
> > + and a freeform string value. If the revision is known locally, it
> > + is converted to a rev, otherwise the record is skipped.
> > +
> > + Note that both key and value are treated as UTF-8 and converted to
> > + the local encoding. This allows uniformity between local and
> > + remote data sources.
> That's a bit unfortunate. If we're expecting them to be read as UTF-8, can't
> we just keep them in UTF-8 all the way thru?
We always work internally in the local encoding. Sane local encodings include:
utf-8. We've normally got two strategies: files owned by users and stored in
local encoding (hgrc) and files owned by Mercurial and stored in utf-8
(bookmarks). So this note is to point out that this is different from the usual
case.. because URLs might (or might not) be remote, shared resources that need
to be in utf-8 for portability.
> >
> > + """
> > +
> > + spec = repo.ui.config("extdata", source)
> > + if not spec:
> > + raise util.Abourt(_("unknown extdata source '%s'") % source)
> Typo here. I suppose there's no great way to test against this.
Indeed, both of the current callers prevent this code from being reached.
> >
> > +
> > + try:
> > + # prepare for future expansion
> > + expand = spec % ()
> > + except TypeError:
> > + raise error.Abort(_("extdata doesn't support parameters yet"),
> > + hint=_("use double % for escaping"))
> > +
> > + data = {}
> > + if spec.startswith("shell:"):
> > + # external commands should be run relative to the repo root
> > + cmd = spec[6:]
> > + cwd = os.getcwd()
> > + os.chdir(repo.root)
> > + try:
> > + src = util.popen(cmd)
> Erm, don't we want to use util.popen2 or one of the other variants that use
> subprocess instead?
The universal advantages of subprocess are overstated. For the simple task of
reading stdout from a subprocess, util.popen is perfectly suited. If it wasn't..
we'd fix util.popen.
> ...and maybe handle ENOENT gracefully?
We can't, because cmd is an arbitrary shell expression.
> pacem in terris / мир / शान्ति / سَلاَم / 平和
> Kevin R. Bullock
--
Mathematics is the supreme nostalgia of our time.
_______________________________________________
Mercurial-devel mailing list
Mercurial-devel@mercurial-scm.org
https://www.mercurial-scm.org/mailman/listinfo/mercurial-devel
