[PATCH 1/2] git svn dcommit: new option --interactive.

["Frédéric Heitzmann" <frederic.heitzmann@gmail.com>]

Allow the user to check the patch set before it is commited to SNV. It is then
possible to accept/discard one patch, accept all, or quit.

This interactive mode is similar with 'git send email' behaviour. However,
'git svn dcommit' returns as soon as one patch is discarded.

Part of the code was taken from git-send-email.perl

Thanks-to: Eric Wong <normalperson@yhbt.net> for the initial idea.
Signed-off-by: Frédéric Heitzmann <frederic.heitzmann@gmail.com>
---

 I would have preferred not duplicating the code snippets taken from
 git-send-email ('ask' function, Term related code, ...) but I preferred not
 to spoil Git.pm with it.
 Any comment on a better way to factor perl code would be appreciated.

 Documentation/git-svn.txt |    8 +++++
 git-svn.perl              |   71 ++++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 78 insertions(+), 1 deletions(-)

diff --git a/Documentation/git-svn.txt b/Documentation/git-svn.txt
index ed5eca1..08188a5 100644
--- a/Documentation/git-svn.txt
+++ b/Documentation/git-svn.txt
@@ -214,6 +214,14 @@ discouraged.
 	version 1.5 can make use of it. 'git svn' currently does not use it
 	and does not set it automatically.
 
+--interactive;;
+	Ask the user to confirm that a patch set should actually be sent to SVN.
+	For each patch, one may answer "yes" (accept this patch), "no" (discard this
+	patch), "all" (accept all patches), or "quit".
+	+
+	'git svn dcommit' returns immediately if answer if "no" or "quit", without
+	commiting anything to SVN.
+
 'branch'::
 	Create a branch in the SVN repository.
 
diff --git a/git-svn.perl b/git-svn.perl
index 89f83fd..fd5eaa2 100755
--- a/git-svn.perl
+++ b/git-svn.perl
@@ -87,7 +87,7 @@ my ($_stdin, $_help, $_edit,
 	$_version, $_fetch_all, $_no_rebase, $_fetch_parent,
 	$_merge, $_strategy, $_dry_run, $_local,
 	$_prefix, $_no_checkout, $_url, $_verbose,
-	$_git_format, $_commit_url, $_tag, $_merge_info);
+	$_git_format, $_commit_url, $_tag, $_merge_info, $_interactive);
 $Git::SVN::_follow_parent = 1;
 $_q ||= 0;
 my %remote_opts = ( 'username=s' => \$Git::SVN::Prompt::_username,
@@ -158,6 +158,7 @@ my %cmd = (
 			  'revision|r=i' => \$_revision,
 			  'no-rebase' => \$_no_rebase,
 			  'mergeinfo=s' => \$_merge_info,
+			  'interactive|i' => \$_interactive,
 			%cmt_opts, %fc_opts } ],
 	branch => [ \&cmd_branch,
 	            'Create a branch in the SVN repository',
@@ -251,6 +252,27 @@ my %cmd = (
 		{} ],
 );
 
+use Term::ReadLine;
+package FakeTerm;
+sub new {
+	my ($class, $reason) = @_;
+	return bless \$reason, shift;
+}
+sub readline {
+	my $self = shift;
+	die "Cannot use readline on FakeTerm: $$self";
+}
+package main;
+
+my $term = eval {
+	$ENV{"GIT_SVN_NOTTY"}
+		? new Term::ReadLine 'git-svn', \*STDIN, \*STDOUT
+		: new Term::ReadLine 'git-svn';
+};
+if ($@) {
+	$term = new FakeTerm "$@: going non-interactive";
+}
+
 my $cmd;
 for (my $i = 0; $i < @ARGV; $i++) {
 	if (defined $cmd{$ARGV[$i]}) {
@@ -361,6 +383,31 @@ sub version {
 	exit 0;
 }
 
+sub ask {
+	my ($prompt, %arg) = @_;
+	my $valid_re = $arg{valid_re};
+	my $default = $arg{default};
+	my $resp;
+	my $i = 0;
+	return defined $default ? $default : undef
+		unless defined $term->IN and defined fileno($term->IN) and
+		       defined $term->OUT and defined fileno($term->OUT);
+	while ($i++ < 10) {
+		$resp = $term->readline($prompt);
+		if (!defined $resp) { # EOF
+			print "\n";
+			return defined $default ? $default : undef;
+		}
+		if ($resp eq '' and defined $default) {
+			return $default;
+		}
+		if (!defined $valid_re or $resp =~ /$valid_re/) {
+			return $resp;
+		}
+	}
+	return undef;
+}
+
 sub do_git_init_db {
 	unless (-d $ENV{GIT_DIR}) {
 		my @init_db = ('init');
@@ -546,6 +593,28 @@ sub cmd_dcommit {
 		     "If these changes depend on each other, re-running ",
 		     "without --no-rebase may be required."
 	}
+
+	if (defined $_interactive){
+		my $ask_default = "y";
+		foreach my $d (@$linear_refs){
+			print "debug : d = $d\n";
+			my ($fh, $ctx) = command_output_pipe(qw(show --summary), "$d");
+			while (<$fh>){
+				print $_;
+			}
+			command_close_pipe($fh, $ctx);
+			$_ = ask("Commit this patch to SVN? ([y]es (default)|[n]o|[q]uit|[a]ll): ",
+			         valid_re => qr/^(?:yes|y|no|n|quit|q|all|a)/i,
+			         default => $ask_default);
+			die "Commit this patch reply required" unless defined $_;
+			if (/^[nq]/i) {
+				exit(0);
+			} elsif (/^a/i) {
+				last;
+			}
+		}
+	}
+
 	my $expect_url = $url;
 	Git::SVN::remove_username($expect_url);
 	while (1) {
-- 
1.7.6.447.gb9176