git-svn: New flag to emulate empty directories
[gitweb.git] / git-svn.perl
index da3fea8bd2c857bbc2e841dec7545318b3b9354e..96f373f81a7716b6690a1e9c1519860fcfbc06c6 100755 (executable)
@@ -89,6 +89,7 @@ BEGIN
        $_prefix, $_no_checkout, $_url, $_verbose,
        $_git_format, $_commit_url, $_tag, $_merge_info);
 $Git::SVN::_follow_parent = 1;
+$SVN::Git::Fetcher::_placeholder_filename = ".gitignore";
 $_q ||= 0;
 my %remote_opts = ( 'username=s' => \$Git::SVN::Prompt::_username,
                     'config-dir=s' => \$Git::SVN::Ra::config_dir,
@@ -139,6 +140,10 @@ BEGIN
                           %fc_opts } ],
        clone => [ \&cmd_clone, "Initialize and fetch revisions",
                        { 'revision|r=s' => \$_revision,
+                         'preserve-empty-dirs' =>
+                               \$SVN::Git::Fetcher::_preserve_empty_dirs,
+                         'placeholder-filename=s' =>
+                               \$SVN::Git::Fetcher::_placeholder_filename,
                           %fc_opts, %init_opts } ],
        init => [ \&cmd_init, "Initialize a repo for tracking" .
                          " (requires URL argument)",
@@ -386,6 +391,12 @@ sub do_git_init_db {
        my $ignore_regex = \$SVN::Git::Fetcher::_ignore_regex;
        command_noisy('config', "$pfx.ignore-paths", $$ignore_regex)
                if defined $$ignore_regex;
+
+       if (defined $SVN::Git::Fetcher::_preserve_empty_dirs) {
+               my $fname = \$SVN::Git::Fetcher::_placeholder_filename;
+               command_noisy('config', "$pfx.preserve-empty-dirs", 'true');
+               command_noisy('config', "$pfx.placeholder-filename", $$fname);
+       }
 }
 
 sub init_subdir {
@@ -784,6 +795,15 @@ sub cmd_find_rev {
        print "$result\n" if $result;
 }
 
+sub auto_create_empty_directories {
+       my ($gs) = @_;
+       my $var = eval { command_oneline('config', '--get', '--bool',
+                                        "svn-remote.$gs->{repo_id}.automkdirs") };
+       # By default, create empty directories by consulting the unhandled log,
+       # but allow setting it to 'false' to skip it.
+       return !($var && $var eq 'false');
+}
+
 sub cmd_rebase {
        command_noisy(qw/update-index --refresh/);
        my ($url, $rev, $uuid, $gs) = working_head_info('HEAD');
@@ -807,7 +827,9 @@ sub cmd_rebase {
                $_fetch_all ? $gs->fetch_all : $gs->fetch;
        }
        command_noisy(rebase_cmd(), $gs->refname);
-       $gs->mkemptydirs;
+       if (auto_create_empty_directories($gs)) {
+               $gs->mkemptydirs;
+       }
 }
 
 sub cmd_show_ignore {
@@ -1245,7 +1267,9 @@ sub post_fetch_checkout {
        command_noisy(qw/read-tree -m -u -v HEAD HEAD/);
        print STDERR "Checked out HEAD:\n  ",
                     $gs->full_url, " r", $gs->last_rev, "\n";
-       $gs->mkemptydirs($gs->last_rev);
+       if (auto_create_empty_directories($gs)) {
+               $gs->mkemptydirs($gs->last_rev);
+       }
 }
 
 sub complete_svn_url {
@@ -3111,8 +3135,12 @@ sub lookup_svn_merge {
                        next;
                }
 
-               push @merged_commit_ranges,
-                       "$bottom_commit^..$top_commit";
+               if (scalar(command('rev-parse', "$bottom_commit^@"))) {
+                       push @merged_commit_ranges,
+                            "$bottom_commit^..$top_commit";
+               } else {
+                       push @merged_commit_ranges, "$top_commit";
+               }
 
                if ( !defined $tip or $top > $tip ) {
                        $tip = $top;
@@ -3141,9 +3169,9 @@ sub check_cherry_pick {
        my $parents = shift;
        my @ranges = @_;
        my %commits = map { $_ => 1 }
-               _rev_list("--no-merges", $tip, "--not", $base, @$parents);
+               _rev_list("--no-merges", $tip, "--not", $base, @$parents, "--");
        for my $range ( @ranges ) {
-               delete @commits{_rev_list($range)};
+               delete @commits{_rev_list($range, "--")};
        }
        for my $commit (keys %commits) {
                if (has_no_changes($commit)) {
@@ -4063,12 +4091,13 @@ sub _read_password {
 }
 
 package SVN::Git::Fetcher;
-use vars qw/@ISA/;
+use vars qw/@ISA $_ignore_regex $_preserve_empty_dirs $_placeholder_filename
+            @deleted_gpath %added_placeholder $repo_id/;
 use strict;
 use warnings;
 use Carp qw/croak/;
+use File::Basename qw/dirname/;
 use IO::File qw//;
-use vars qw/$_ignore_regex/;
 
 # file baton members: path, mode_a, mode_b, pool, fh, blob, base
 sub new {
@@ -4080,8 +4109,34 @@ sub new {
                $self->{empty_symlinks} =
                                  _mark_empty_symlinks($git_svn, $switch_path);
        }
-       $self->{ignore_regex} = eval { command_oneline('config', '--get',
-                            "svn-remote.$git_svn->{repo_id}.ignore-paths") };
+
+       # some options are read globally, but can be overridden locally
+       # per [svn-remote "..."] section.  Command-line options will *NOT*
+       # override options set in an [svn-remote "..."] section
+       $repo_id = $git_svn->{repo_id};
+       my $k = "svn-remote.$repo_id.ignore-paths";
+       my $v = eval { command_oneline('config', '--get', $k) };
+       $self->{ignore_regex} = $v;
+
+       $k = "svn-remote.$repo_id.preserve-empty-dirs";
+       $v = eval { command_oneline('config', '--get', '--bool', $k) };
+       if ($v && $v eq 'true') {
+               $_preserve_empty_dirs = 1;
+               $k = "svn-remote.$repo_id.placeholder-filename";
+               $v = eval { command_oneline('config', '--get', $k) };
+               $_placeholder_filename = $v;
+       }
+
+       # Load the list of placeholder files added during previous invocations.
+       $k = "svn-remote.$repo_id.added-placeholder";
+       $v = eval { command_oneline('config', '--get-all', $k) };
+       if ($_preserve_empty_dirs && $v) {
+               # command() prints errors to stderr, so we only call it if
+               # command_oneline() succeeded.
+               my @v = command('config', '--get-all', $k);
+               $added_placeholder{ dirname($_) } = $_ foreach @v;
+       }
+
        $self->{empty} = {};
        $self->{dir_prop} = {};
        $self->{file_prop} = {};
@@ -4210,6 +4265,8 @@ sub delete_entry {
                $self->{gii}->remove($gpath);
                print "\tD\t$gpath\n" unless $::_q;
        }
+       # Don't add to @deleted_gpath if we're deleting a placeholder file.
+       push @deleted_gpath, $gpath unless $added_placeholder{dirname($path)};
        $self->{empty}->{$path} = 0;
        undef;
 }
@@ -4242,7 +4299,15 @@ sub add_file {
                my ($dir, $file) = ($path =~ m#^(.*?)/?([^/]+)$#);
                delete $self->{empty}->{$dir};
                $mode = '100644';
+
+               if ($added_placeholder{$dir}) {
+                       # Remove our placeholder file, if we created one.
+                       delete_entry($self, $added_placeholder{$dir})
+                               unless $path eq $added_placeholder{$dir};
+                       delete $added_placeholder{$dir}
+               }
        }
+
        { path => $path, mode_a => $mode, mode_b => $mode,
          pool => SVN::Pool->new, action => 'A' };
 }
@@ -4260,6 +4325,7 @@ sub add_directory {
                        chomp;
                        $self->{gii}->remove($_);
                        print "\tD\t$_\n" unless $::_q;
+                       push @deleted_gpath, $gpath;
                }
                command_close_pipe($ls, $ctx);
                $self->{empty}->{$path} = 0;
@@ -4267,6 +4333,13 @@ sub add_directory {
        my ($dir, $file) = ($path =~ m#^(.*?)/?([^/]+)$#);
        delete $self->{empty}->{$dir};
        $self->{empty}->{$path} = 1;
+
+       if ($added_placeholder{$dir}) {
+               # Remove our placeholder file, if we created one.
+               delete_entry($self, $added_placeholder{$dir});
+               delete $added_placeholder{$dir}
+       }
+
 out:
        { path => $path };
 }
@@ -4430,12 +4503,96 @@ sub abort_edit {
 
 sub close_edit {
        my $self = shift;
+
+       if ($_preserve_empty_dirs) {
+               my @empty_dirs;
+
+               # Any entry flagged as empty that also has an associated
+               # dir_prop represents a newly created empty directory.
+               foreach my $i (keys %{$self->{empty}}) {
+                       push @empty_dirs, $i if exists $self->{dir_prop}->{$i};
+               }
+
+               # Search for directories that have become empty due subsequent
+               # file deletes.
+               push @empty_dirs, $self->find_empty_directories();
+
+               # Finally, add a placeholder file to each empty directory.
+               $self->add_placeholder_file($_) foreach (@empty_dirs);
+
+               $self->stash_placeholder_list();
+       }
+
        $self->{git_commit_ok} = 1;
        $self->{nr} = $self->{gii}->{nr};
        delete $self->{gii};
        $self->SUPER::close_edit(@_);
 }
 
+sub find_empty_directories {
+       my ($self) = @_;
+       my @empty_dirs;
+       my %dirs = map { dirname($_) => 1 } @deleted_gpath;
+
+       foreach my $dir (sort keys %dirs) {
+               next if $dir eq ".";
+
+               # If there have been any additions to this directory, there is
+               # no reason to check if it is empty.
+               my $skip_added = 0;
+               foreach my $t (qw/dir_prop file_prop/) {
+                       foreach my $path (keys %{ $self->{$t} }) {
+                               if (exists $self->{$t}->{dirname($path)}) {
+                                       $skip_added = 1;
+                                       last;
+                               }
+                       }
+                       last if $skip_added;
+               }
+               next if $skip_added;
+
+               # Use `git ls-tree` to get the filenames of this directory
+               # that existed prior to this particular commit.
+               my $ls = command('ls-tree', '-z', '--name-only',
+                                $self->{c}, "$dir/");
+               my %files = map { $_ => 1 } split(/\0/, $ls);
+
+               # Remove the filenames that were deleted during this commit.
+               delete $files{$_} foreach (@deleted_gpath);
+
+               # Report the directory if there are no filenames left.
+               push @empty_dirs, $dir unless (scalar %files);
+       }
+       @empty_dirs;
+}
+
+sub add_placeholder_file {
+       my ($self, $dir) = @_;
+       my $path = "$dir/$_placeholder_filename";
+       my $gpath = $self->git_path($path);
+
+       my $fh = $::_repository->temp_acquire($gpath);
+       my $hash = $::_repository->hash_and_insert_object(Git::temp_path($fh));
+       Git::temp_release($fh, 1);
+       $self->{gii}->update('100644', $hash, $gpath) or croak $!;
+
+       # The directory should no longer be considered empty.
+       delete $self->{empty}->{$dir} if exists $self->{empty}->{$dir};
+
+       # Keep track of any placeholder files we create.
+       $added_placeholder{$dir} = $path;
+}
+
+sub stash_placeholder_list {
+       my ($self) = @_;
+       my $k = "svn-remote.$repo_id.added-placeholder";
+       my $v = eval { command_oneline('config', '--get-all', $k) };
+       command_noisy('config', '--unset-all', $k) if $v;
+       foreach (values %added_placeholder) {
+               command_noisy('config', '--add', $k, $_);
+       }
+}
+
 package SVN::Git::Editor;
 use vars qw/@ISA $_rmdir $_cp_similarity $_find_copies_harder $_rename_limit/;
 use strict;