From: Jani Nikula <jani@nikula.org>
To: Tomi Ollila <tomi.ollila@iki.fi>, notmuch@notmuchmail.org
Subject: Re: [PATCH v2 2/3] cli: refactor "notmuch tag" query tagging into a
	separate function
In-Reply-To: <m2398we5id.fsf@guru.guru-group.fi>
References: <cover.1332702915.git.jani@nikula.org>
	<584067da00dd9f04a7f3982b76fd4b4918e4fe61.1332702915.git.jani@nikula.org>
	<m262dse7f0.fsf@guru.guru-group.fi>
	<87limo2xpk.fsf@nikula.org>User-Agent: Notmuch/0.12+71~gdacf76b
	(http://notmuchmail.org) Emacs/23.3.1
	(x86_64-unknown-linux-gnu) <m2398we5id.fsf@guru.guru-group.fi>
User-Agent: Notmuch/0.11.1+222~ga47a98c (http://notmuchmail.org) Emacs/23.1.1
	(i686-pc-linux-gnu)
Date: Mon, 26 Mar 2012 07:38:47 +0000
Message-ID: <87ty1b4xrs.fsf@nikula.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Precedence: list

On Mon, 26 Mar 2012 00:26:50 +0300, Tomi Ollila <tomi.ollila@iki.fi> wrote:
> Jani Nikula <jani@nikula.org> writes:
> 
> > On Sun, 25 Mar 2012 23:45:39 +0300, Tomi Ollila <tomi.ollila@iki.fi> wrote:
> >> Jani Nikula <jani@nikula.org> writes:
> >> 
> >> > Refactor to make tagging code easier to reuse in the future. No
> >> > functional changes.
> >> >
> >> > Signed-off-by: Jani Nikula <jani@nikula.org>
> >> > ---
> >> 
> >> tag_query() is pretty generic name for a function which (also) does
> >> tagging operations (adds and removes tags based on tag_ops).
> >
> > Mmmh, if you think of "tag" as a verb, it fairly accurately describes
> > what the function does: tag (messages matching this) query (according
> > given arguments). I don't mind changing, but can't come up with anything
> > better right now either. notmuch_{search,query}_change_tags()? Meh?
> 
> Hmmm, yes... -- tag...query... ok, I can live with that if no-one
> else get same impression I got first...
> 
> >
> >> If, however, tag_opts != NULL (as is needs to be) but tag_opts[0] == NULL
> >> (now tag_query() would not do any tagging operations, but
> >> optimize_tag_query would mangle query string ( '*' to '()' and 
> >> 'any_other' to '( any_other ) and ()' )
> >
> > I'm not sure I follow you. AFAICT the behaviour does not change from
> > what it was before, apart from the tag addition and removal being mixed
> > together.
> 
> The thing is that notmuch_tag_command () check that there is at least
> one tagging operation to be done, but tag_query () doesn't do such
> checking...
> 
> >> I.e. IMO the function name should be more spesific & the fact that this
> >> function needs tag changing data in tag_ops array should be documented.
> >
> > Documentation good. :)
> 
> ... therefore the requirement that there needs to tagging information
> in tag_ops is in place.

Actually, no. In the future (the follow-up patches are in my local
tree...) tag_query() should work also when there are no tagging
operations. I'll either need to fix tag_query() or _optimize_tag_query()
to handle this gracefully. Thanks for spelling this out for me! :)

> >> Minor thing in patch #1:
> >> 
> >>  +	    tag_ops[tag_ops_count].remove = argv[i][0] == '-';
> >> 
> >> would be more clearer as:
> >> 
> >>  +	    tag_ops[tag_ops_count].remove = (argv[i][0] == '-');
> >
> > I usually don't add braces where they aren't needed, but can do here.
> 
> Assigment is much lower in precedence than equality comparison -- but
> as this is so seldom-used construct, humans read (with understanding)
> the code faster with this added clarity.

Sounds reasonable.

BR,
Jani.



> 
> >> Everything else LGTM.
> >
> > Thanks for the review,
> > Jani.
> >
> >> 
> >> Tomi
> 
> Tomi
> 
> >> 
> >> 
> >> >  notmuch-tag.c |  101 ++++++++++++++++++++++++++++++++-------------------------
> >> >  1 files changed, 57 insertions(+), 44 deletions(-)
> >> >
> >> > diff --git a/notmuch-tag.c b/notmuch-tag.c
> >> > index c39b235..edbfdec 100644
> >> > --- a/notmuch-tag.c
> >> > +++ b/notmuch-tag.c
> >> > @@ -106,6 +106,60 @@ _optimize_tag_query (void *ctx, const char *orig_query_string,
> >> >      return query_string;
> >> >  }
> >> >  
> >> > +static int
> >> > +tag_query (void *ctx, notmuch_database_t *notmuch, const char *query_string,
> >> > +	   tag_operation_t *tag_ops, notmuch_bool_t synchronize_flags)
> >> > +{
> >> > +    notmuch_query_t *query;
> >> > +    notmuch_messages_t *messages;
> >> > +    notmuch_message_t *message;
> >> > +    int i;
> >> > +
> >> > +    /* Optimize the query so it excludes messages that already have
> >> > +     * the specified set of tags. */
> >> > +    query_string = _optimize_tag_query (ctx, query_string, tag_ops);
> >> > +    if (query_string == NULL) {
> >> > +	fprintf (stderr, "Out of memory.\n");
> >> > +	return 1;
> >> > +    }
> >> > +
> >> > +    query = notmuch_query_create (notmuch, query_string);
> >> > +    if (query == NULL) {
> >> > +	fprintf (stderr, "Out of memory.\n");
> >> > +	return 1;
> >> > +    }
> >> > +
> >> > +    /* tagging is not interested in any special sort order */
> >> > +    notmuch_query_set_sort (query, NOTMUCH_SORT_UNSORTED);
> >> > +
> >> > +    for (messages = notmuch_query_search_messages (query);
> >> > +	 notmuch_messages_valid (messages) && !interrupted;
> >> > +	 notmuch_messages_move_to_next (messages))
> >> > +    {
> >> > +	message = notmuch_messages_get (messages);
> >> > +
> >> > +	notmuch_message_freeze (message);
> >> > +
> >> > +	for (i = 0; tag_ops[i].tag; i++) {
> >> > +	    if (tag_ops[i].remove)
> >> > +		notmuch_message_remove_tag (message, tag_ops[i].tag);
> >> > +	    else
> >> > +		notmuch_message_add_tag (message, tag_ops[i].tag);
> >> > +	}
> >> > +
> >> > +	notmuch_message_thaw (message);
> >> > +
> >> > +	if (synchronize_flags)
> >> > +	    notmuch_message_tags_to_maildir_flags (message);
> >> > +
> >> > +	notmuch_message_destroy (message);
> >> > +    }
> >> > +
> >> > +    notmuch_query_destroy (query);
> >> > +
> >> > +    return interrupted;
> >> > +}
> >> > +
> >> >  int
> >> >  notmuch_tag_command (void *ctx, int argc, char *argv[])
> >> >  {
> >> > @@ -114,12 +168,10 @@ notmuch_tag_command (void *ctx, int argc, char *argv[])
> >> >      char *query_string;
> >> >      notmuch_config_t *config;
> >> >      notmuch_database_t *notmuch;
> >> > -    notmuch_query_t *query;
> >> > -    notmuch_messages_t *messages;
> >> > -    notmuch_message_t *message;
> >> >      struct sigaction action;
> >> >      notmuch_bool_t synchronize_flags;
> >> >      int i;
> >> > +    int ret;
> >> >  
> >> >      /* Setup our handler for SIGINT */
> >> >      memset (&action, 0, sizeof (struct sigaction));
> >> > @@ -166,14 +218,6 @@ notmuch_tag_command (void *ctx, int argc, char *argv[])
> >> >  	return 1;
> >> >      }
> >> >  
> >> > -    /* Optimize the query so it excludes messages that already have
> >> > -     * the specified set of tags. */
> >> > -    query_string = _optimize_tag_query (ctx, query_string, tag_ops);
> >> > -    if (query_string == NULL) {
> >> > -	fprintf (stderr, "Out of memory.\n");
> >> > -	return 1;
> >> > -    }
> >> > -
> >> >      config = notmuch_config_open (ctx, NULL, NULL);
> >> >      if (config == NULL)
> >> >  	return 1;
> >> > @@ -185,40 +229,9 @@ notmuch_tag_command (void *ctx, int argc, char *argv[])
> >> >  
> >> >      synchronize_flags = notmuch_config_get_maildir_synchronize_flags (config);
> >> >  
> >> > -    query = notmuch_query_create (notmuch, query_string);
> >> > -    if (query == NULL) {
> >> > -	fprintf (stderr, "Out of memory.\n");
> >> > -	return 1;
> >> > -    }
> >> > -
> >> > -    /* tagging is not interested in any special sort order */
> >> > -    notmuch_query_set_sort (query, NOTMUCH_SORT_UNSORTED);
> >> > +    ret = tag_query (ctx, notmuch, query_string, tag_ops, synchronize_flags);
> >> >  
> >> > -    for (messages = notmuch_query_search_messages (query);
> >> > -	 notmuch_messages_valid (messages) && !interrupted;
> >> > -	 notmuch_messages_move_to_next (messages))
> >> > -    {
> >> > -	message = notmuch_messages_get (messages);
> >> > -
> >> > -	notmuch_message_freeze (message);
> >> > -
> >> > -	for (i = 0; tag_ops[i].tag; i++) {
> >> > -	    if (tag_ops[i].remove)
> >> > -		notmuch_message_remove_tag (message, tag_ops[i].tag);
> >> > -	    else
> >> > -		notmuch_message_add_tag (message, tag_ops[i].tag);
> >> > -	}
> >> > -
> >> > -	notmuch_message_thaw (message);
> >> > -
> >> > -	if (synchronize_flags)
> >> > -	    notmuch_message_tags_to_maildir_flags (message);
> >> > -
> >> > -	notmuch_message_destroy (message);
> >> > -    }
> >> > -
> >> > -    notmuch_query_destroy (query);
> >> >      notmuch_database_close (notmuch);
> >> >  
> >> > -    return interrupted;
> >> > +    return ret;
> >> >  }
> >> > -- 
> >> > 1.7.5.4
> >> >
> >> > _______________________________________________
> >> > notmuch mailing list
> >> > notmuch@notmuchmail.org
> >> > http://notmuchmail.org/mailman/listinfo/notmuch
> > _______________________________________________
> > notmuch mailing list
> > notmuch@notmuchmail.org
> > http://notmuchmail.org/mailman/listinfo/notmuch