git-svn: implement git svn create-ignore

git svn create-ignore (to create one .gitignore per directory
from the svn:ignore properties.  This has the disadvantage of
committing the .gitignore during the next dcommit, but when you
import a repo with tons of ignores (>1000), using git svn show-ignore
to build .git/info/exclude is *not* a good idea, because things like
git-status will end up doing >1000 fnmatch *per file* in the repo,
which leads to git-status taking more than 4s on my Core2Duo 2Ghz 2G
RAM)

	* git-svn.perl (%cmd): Add the new command `create-ignore'.
	(&cmd_create_ignore): New.
	* t/t9101-git-svn-props.sh: Adjust the test-case for show-ignore and
	add a test case for create-ignore.

[ew: added commit message from
  <05CAB148-56ED-4FF1-8AAB-4BA2A0B70C2C@lrde.epita.fr> ]

Signed-off-by: Benoit Sigoure <tsuna@lrde.epita.fr>
Acked-by: Eric Wong <normalperson@yhbt.net>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

git-svn.perl

@@ -123,6 +123,10 @@ my %cmd = (
 	'set-tree' => [ \&cmd_set_tree,
 	                "Set an SVN repository to a git tree-ish",
 			{ 'stdin|' => \$_stdin, %cmt_opts, %fc_opts, } ],
+	'create-ignore' => [ \&cmd_create_ignore,
+			     'Create a .gitignore per svn:ignore',
+			     { 'revision|r=i' => \$_revision
+			     } ],
 	'show-ignore' => [ \&cmd_show_ignore, "Show svn:ignore listings",
 			{ 'revision|r=i' => \$_revision
 			} ],
@@ -499,6 +503,29 @@ sub cmd_show_ignore {
 	});
 }
 
+sub cmd_create_ignore {
+	my ($url, $rev, $uuid, $gs) = working_head_info('HEAD');
+	$gs ||= Git::SVN->new;
+	my $r = (defined $_revision ? $_revision : $gs->ra->get_latest_revnum);
+	$gs->prop_walk($gs->{path}, $r, sub {
+		my ($gs, $path, $props) = @_;
+		# $path is of the form /path/to/dir/
+		my $ignore = '.' . $path . '.gitignore';
+		my $s = $props->{'svn:ignore'} or return;
+		open(GITIGNORE, '>', $ignore)
+		  or fatal("Failed to open `$ignore' for writing: $!\n");
+		$s =~ s/[\r\n]+/\n/g;
+		chomp $s;
+		# Prefix all patterns so that the ignore doesn't apply
+		# to sub-directories.
+		$s =~ s#^#/#gm;
+		print GITIGNORE "$s\n";
+		close(GITIGNORE)
+		  or fatal("Failed to close `$ignore': $!\n");
+		command_noisy('add', $ignore);
+	});
+}
+
 sub cmd_multi_init {
 	my $url = shift;
 	unless (defined $_trunk || defined $_branches || defined $_tags) {

t/t9101-git-svn-props.sh

@@ -126,19 +126,20 @@ cat > show-ignore.expect <<\EOF
 # /
 /no-such-file*
 
-# deeply
+# /deeply/
 /deeply/no-such-file*
 
-# deeply/nested
+# /deeply/nested/
 /deeply/nested/no-such-file*
 
-# deeply/nested/directory
+# /deeply/nested/directory/
 /deeply/nested/directory/no-such-file*
 EOF
 
 test_expect_success 'test show-ignore' "
 	cd test_wc &&
 	mkdir -p deeply/nested/directory &&
+	touch deeply/nested/directory/.keep &&
 	svn add deeply &&
 	svn up &&
 	svn propset -R svn:ignore 'no-such-file*' .
@@ -148,4 +149,25 @@ test_expect_success 'test show-ignore' "
 	cmp show-ignore.expect show-ignore.got
 	"
 
+cat >create-ignore.expect <<\EOF
+/no-such-file*
+EOF
+
+cat >create-ignore-index.expect <<\EOF
+100644 8c52e5dfcd0a8b6b6bcfe6b41b89bcbf493718a5 0	.gitignore
+100644 8c52e5dfcd0a8b6b6bcfe6b41b89bcbf493718a5 0	deeply/.gitignore
+100644 8c52e5dfcd0a8b6b6bcfe6b41b89bcbf493718a5 0	deeply/nested/.gitignore
+100644 8c52e5dfcd0a8b6b6bcfe6b41b89bcbf493718a5 0	deeply/nested/directory/.gitignore
+EOF
+
+test_expect_success 'test create-ignore' "
+	git-svn fetch && git pull . remotes/git-svn &&
+	git-svn create-ignore &&
+	cmp ./.gitignore create-ignore.expect &&
+	cmp ./deeply/.gitignore create-ignore.expect &&
+	cmp ./deeply/nested/.gitignore create-ignore.expect &&
+	cmp ./deeply/nested/directory/.gitignore create-ignore.expect &&
+	git ls-files -s | grep gitignore | cmp - create-ignore-index.expect
+	"
+
 test_done