Merge 'add-p-many-files'

This topic branch allows `add -p` and `add -i` with a large number of
files. It is kind of a hack that was never really meant to be
upstreamed. Let's see if we can do better in the built-in `add -p`.

Signed-off-by: Johannes Schindelin <[email protected]>

Author: dscho

git-add--interactive.perl

@@ -174,6 +174,24 @@ sub run_cmd_pipe {
 		die "$^O does not support: @invalid\n" if @invalid;
 		my @args = map { m/ /o ? "\"$_\"": $_ } @_;
 		return qx{@args};
+	} elsif (($^O eq 'MSWin32' || $^O eq 'msys') && (scalar @_ > 200) &&
+			grep $_ eq '--', @_) {
+		use File::Temp qw(tempfile);
+		my ($fhargs, $filename) =
+			tempfile('git-args-XXXXXX', UNLINK => 1);
+
+		my $cmd = 'cat '.$filename.' | xargs -0 -s 20000 ';
+		while ($_[0] ne '--') {
+			$cmd = $cmd . shift(@_) . ' ';
+		}
+
+		shift(@_);
+		print $fhargs join("\0", @_);
+		close($fhargs);
+
+		my $fh = undef;
+		open($fh, '-|', $cmd) or die;
+		return <$fh>;
 	} else {
 		my $fh = undef;
 		open($fh, '-|', @_) or die;

t/t3701-add-interactive.sh

@@ -805,6 +805,27 @@ test_expect_success 'checkout -p works with pathological context lines' '
 	test_cmp expect a
 '
 
+test_expect_success EXPENSIVE 'add -i with a lot of files' '
+	git reset --hard &&
+	x160=0123456789012345678901234567890123456789 &&
+	x160=$x160$x160$x160$x160 &&
+	y= &&
+	i=0 &&
+	while test $i -le 200
+	do
+		name=$(printf "%s%03d" $x160 $i) &&
+		echo $name >$name &&
+		git add -N $name &&
+		y="${y}y$LF" &&
+		i=$(($i+1)) ||
+		break
+	done &&
+	echo "$y" | git add -p -- . &&
+	git diff --cached >staged &&
+	test_line_count = 1407 staged &&
+	git reset --hard
+'
+
 test_expect_success 'show help from add--helper' '
 	git reset --hard &&
 	cat >expect <<-EOF &&