From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-3.8 required=3.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD shortcircuit=no autolearn=ham autolearn_force=no version=3.4.0 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by dcvr.yhbt.net (Postfix) with ESMTP id 522AE20401 for ; Thu, 15 Jun 2017 16:31:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751888AbdFOQa6 (ORCPT ); Thu, 15 Jun 2017 12:30:58 -0400 Received: from cloud.peff.net ([104.130.231.41]:40881 "EHLO cloud.peff.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751578AbdFOQa5 (ORCPT ); Thu, 15 Jun 2017 12:30:57 -0400 Received: (qmail 7207 invoked by uid 109); 15 Jun 2017 16:30:57 -0000 Received: from Unknown (HELO peff.net) (10.0.1.2) by cloud.peff.net (qpsmtpd/0.84) with SMTP; Thu, 15 Jun 2017 16:30:57 +0000 Received: (qmail 26505 invoked by uid 111); 15 Jun 2017 16:30:59 -0000 Received: from sigill.intra.peff.net (HELO sigill.intra.peff.net) (10.0.0.7) by peff.net (qpsmtpd/0.84) with SMTP; Thu, 15 Jun 2017 12:30:59 -0400 Received: by sigill.intra.peff.net (sSMTP sendmail emulation); Thu, 15 Jun 2017 12:30:55 -0400 Date: Thu, 15 Jun 2017 12:30:55 -0400 From: Jeff King To: git@vger.kernel.org Cc: Scott Baker Subject: [PATCH] diff-highlight: split code into module Message-ID: <20170615163055.b63hcivjogafkerq@sigill.intra.peff.net> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org The diff-so-fancy project is also written in perl, and most of its users pipe diffs through both diff-highlight and diff-so-fancy. It would be nice if this could be done in a single script. So let's pull most of diff-highlight's code into its own module which can be used by diff-so-fancy. In addition, we'll abstract a few basic items like reading from stdio so that a script using the module can do more processing before or after diff-highlight handles the lines. See the README update for more details. One small downside is that the diff-highlight script must now be built using the Makefile. There are ways around this, but it quickly gets into perl arcana. Let's go with the simple solution. As a bonus, our Makefile now respects the PERL_PATH variable if it is set. Signed-off-by: Jeff King --- Scott and I discussed this off-list, and this was the least-gross solution I came up with. The plan would be for diff-so-fancy to pull in this copy of diff-highlight from git.git and have a wrapper script similar to the diff-highlight.perl found here. contrib/diff-highlight/.gitignore | 2 ++ .../{diff-highlight => DiffHighlight.pm} | 40 +++++++++++++--------- contrib/diff-highlight/Makefile | 21 ++++++++++-- contrib/diff-highlight/README | 30 ++++++++++++++++ contrib/diff-highlight/diff-highlight.perl | 8 +++++ 5 files changed, 82 insertions(+), 19 deletions(-) create mode 100644 contrib/diff-highlight/.gitignore rename contrib/diff-highlight/{diff-highlight => DiffHighlight.pm} (91%) mode change 100755 => 100644 create mode 100644 contrib/diff-highlight/diff-highlight.perl diff --git a/contrib/diff-highlight/.gitignore b/contrib/diff-highlight/.gitignore new file mode 100644 index 000000000..c07454824 --- /dev/null +++ b/contrib/diff-highlight/.gitignore @@ -0,0 +1,2 @@ +shebang.perl +diff-highlight diff --git a/contrib/diff-highlight/diff-highlight b/contrib/diff-highlight/DiffHighlight.pm old mode 100755 new mode 100644 similarity index 91% rename from contrib/diff-highlight/diff-highlight rename to contrib/diff-highlight/DiffHighlight.pm index 81bd8040e..663992e53 --- a/contrib/diff-highlight/diff-highlight +++ b/contrib/diff-highlight/DiffHighlight.pm @@ -1,4 +1,4 @@ -#!/usr/bin/perl +package DiffHighlight; use 5.008; use warnings FATAL => 'all'; @@ -29,13 +29,14 @@ my @removed; my @added; my $in_hunk; -# Some scripts may not realize that SIGPIPE is being ignored when launching the -# pager--for instance scripts written in Python. -$SIG{PIPE} = 'DEFAULT'; +our $line_cb = sub { print @_ }; +our $flush_cb = sub { local $| = 1 }; + +sub handle_line { + local $_ = shift; -while (<>) { if (!$in_hunk) { - print; + $line_cb->($_); $in_hunk = /^$GRAPH*$COLOR*\@\@ /; } elsif (/^$GRAPH*$COLOR*-/) { @@ -49,7 +50,7 @@ while (<>) { @removed = (); @added = (); - print; + $line_cb->($_); $in_hunk = /^$GRAPH*$COLOR*[\@ ]/; } @@ -62,15 +63,22 @@ while (<>) { # place to flush. Flushing on a blank line is a heuristic that # happens to match git-log output. if (!length) { - local $| = 1; + $flush_cb->(); } } -# Flush any queued hunk (this can happen when there is no trailing context in -# the final diff of the input). -show_hunk(\@removed, \@added); +sub flush { + # Flush any queued hunk (this can happen when there is no trailing + # context in the final diff of the input). + show_hunk(\@removed, \@added); +} -exit 0; +sub highlight_stdin { + while () { + handle_line($_); + } + flush(); +} # Ideally we would feed the default as a human-readable color to # git-config as the fallback value. But diff-highlight does @@ -88,7 +96,7 @@ sub show_hunk { # If one side is empty, then there is nothing to compare or highlight. if (!@$a || !@$b) { - print @$a, @$b; + $line_cb->(@$a, @$b); return; } @@ -97,17 +105,17 @@ sub show_hunk { # stupid, and only handle multi-line hunks that remove and add the same # number of lines. if (@$a != @$b) { - print @$a, @$b; + $line_cb->(@$a, @$b); return; } my @queue; for (my $i = 0; $i < @$a; $i++) { my ($rm, $add) = highlight_pair($a->[$i], $b->[$i]); - print $rm; + $line_cb->($rm); push @queue, $add; } - print @queue; + $line_cb->(@queue); } sub highlight_pair { diff --git a/contrib/diff-highlight/Makefile b/contrib/diff-highlight/Makefile index 901872452..fbf5c5824 100644 --- a/contrib/diff-highlight/Makefile +++ b/contrib/diff-highlight/Makefile @@ -1,5 +1,20 @@ -# nothing to build -all: +all: diff-highlight -test: +PERL_PATH = /usr/bin/perl +-include ../../config.mak + +PERL_PATH_SQ = $(subst ','\'',$(PERL_PATH)) + +diff-highlight: shebang.perl DiffHighlight.pm diff-highlight.perl + cat $^ >$@+ + chmod +x $@+ + mv $@+ $@ + +shebang.perl: FORCE + @echo '#!$(PERL_PATH_SQ)' >$@+ + @cmp $@+ $@ >/dev/null 2>/dev/null || mv $@+ $@ + +test: all $(MAKE) -C t + +.PHONY: FORCE diff --git a/contrib/diff-highlight/README b/contrib/diff-highlight/README index 836b97a73..d4c234317 100644 --- a/contrib/diff-highlight/README +++ b/contrib/diff-highlight/README @@ -99,6 +99,36 @@ newHighlight = "black #aaffaa" --------------------------------------------- +Using diff-highlight as a module +-------------------------------- + +If you want to pre- or post- process the highlighted lines as part of +another perl script, you can use the DiffHighlight module. You can +either "require" it or just cat the module together with your script (to +avoid run-time dependencies). + +Your script may set up one or more of the following variables: + + - $DiffHighlight::line_cb - this should point to a function which is + called whenever DiffHighlight has lines (which may contain + highlights) to output. The default function prints each line to + stdout. Note that the function may be called with multiple lines. + + - $DiffHighlight::flush_cb - this should point to a function which + flushes the output (because DiffHighlight believes it has completed + processing a logical chunk of input). The default function flushes + stdout. + +The script may then feed lines, one at a time, to DiffHighlight::handle_line(). +When lines are done processing, they will be fed to $line_cb. Note that +DiffHighlight may queue up many input lines (to analyze a whole hunk) +before calling $line_cb. After providing all lines, call +DiffHighlight::flush() to flush any unprocessed lines. + +If you just want to process stdin, DiffHighlight::highlight_stdin() +is a convenience helper which will loop and flush for you. + + Bugs ---- diff --git a/contrib/diff-highlight/diff-highlight.perl b/contrib/diff-highlight/diff-highlight.perl new file mode 100644 index 000000000..9b3e9c1f4 --- /dev/null +++ b/contrib/diff-highlight/diff-highlight.perl @@ -0,0 +1,8 @@ +package main; + +# Some scripts may not realize that SIGPIPE is being ignored when launching the +# pager--for instance scripts written in Python. +$SIG{PIPE} = 'DEFAULT'; + +DiffHighlight::highlight_stdin(); +exit 0; -- 2.13.1.766.g6bea926c5