git-split-ws

#! /usr/bin/perl
# Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
# Contact: http://www.qt-project.org/legal
#
# You may use this file under the terms of the 3-clause BSD license.
# See the file LICENSE from this package for details.
#

use warnings;
use strict;

my $invocationCommand = '';
if ($#ARGV >= 0) {
    $invocationCommand = $ARGV[0];
}

if ($invocationCommand ne 'commit' and $invocationCommand ne 'stash' and $invocationCommand ne '') {
    print STDERR <<EOF ;
Usage: $0 [commit | stash]
Removes white space only change chunks from the HEAD commit.
If invoked with commit, WS changes are committed as a separate commit on top.
If invoked with stash, WS changes are stashed.
Otherwise it will merely reapply the WS changes to the working tree.
EOF
    exit 2;
}

sub printerr()
{
    die "cannot run git: ".$! if ($? < 0);
    die "git crashed with signal ".$? if ($? & 127);
    die "git exited with status ".($? >> 8) if ($?);
}

open STATUS, "git status --porcelain |" or printerr;
while (<STATUS>) {
    if (/^[^ ?!]/) {
        print STDERR "Index is not clean. Aborting.\n";
        exit 1;
    }
}
close STATUS or printerr;

my $patch = "";

my $file = "";
my @filehdr = ("", "");
my $fileHdrShown = 0;

my $chunk = 0;
my @addi = ();
my @deli = ();
my $nonws;
my $ws;
my $mixws_check = 0;
my $lineno = 0;
my $lineno2 = 0;
my @ws_files = ();
my %ws_lines = (); # hash of lists
my $braces = 0;
my $open_key = qr/\s*#\s*if|.*{/;
my $close_key = qr/\s*#\s*endif|.*}/;
my $kill_all_ws = qr/\s+((?:\"(?:\\.|[^\"])*\"|\S)+)/; # Collapse all whitespace not inside strings.
my $kill_nl_ws = qr/((?:\"(?:\\.|[^\"])*\"|\S)+)\s+/; # Collapse all non-leading whitespace not inside strings.

sub flushChunk()
{
    my $loc_nonws = 0;
    my $nlonly = 1;
    my ($ai, $di) = (0, 0);