git svn dcommit: new option --interactive.

Allow the user to check the patch set before it is commited to SVN. 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 (see 'ask' function)

Tests several combinations of potential answers to
'git svn dcommit --interactive'. For each of them, test whether patches
were commited to SVN or not.

Thanks-to Eric Wong <normalperson@yhbt.net> for the initial idea.

Acked-by: Eric Wong <normalperson@yhbt.net>
Signed-off-by: Frédéric Heitzmann <frederic.heitzmann@gmail.com>

3 files changed, 146 insertions, 1 deletions

diff --git a/Documentation/git-svn.txt b/Documentation/git-svn.txt
index f977e8780b..34ee785064 100644
--- a/Documentation/git-svn.txt
+++ b/Documentation/git-svn.txt
@@ -234,6 +234,14 @@ svn:mergeinfo property in the SVN repository when possible. Currently, this can
 only be done when dcommitting non-fast-forward merges where all parents but the
 first have already been pushed into SVN.
 
+--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 a0410f0554..c14d813f40 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;
 $SVN::Git::Fetcher::_placeholder_filename = ".gitignore";
 $_q ||= 0;
@@ -163,6 +163,7 @@ 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',
@@ -256,6 +257,27 @@ 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]}) {
@@ -366,6 +388,36 @@ sub version {
 	exit 0;
 }
 
+sub ask {
+	my ($prompt, %arg) = @_;
+	my $valid_re = $arg{valid_re};
+	my $default = $arg{default};
+	my $resp;
+	my $i = 0;
+
+	if ( !( defined($term->IN)
+            && defined( fileno($term->IN) )
+            && defined( $term->OUT )
+            && defined( fileno($term->OUT) ) ) ){
+		return defined($default) ? $default : undef;
+	}
+
+	while ($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');
@@ -746,6 +798,27 @@ 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){
+			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;
 
 	my $push_merge_info = eval {
diff --git a/t/t9162-git-svn-dcommit-interactive.sh b/t/t9162-git-svn-dcommit-interactive.sh
new file mode 100644
index 0000000000..e38d9fa37b
--- /dev/null
+++ b/t/t9162-git-svn-dcommit-interactive.sh
@@ -0,0 +1,64 @@
+#!/bin/sh
+#
+# Copyright (c) 2011 Frédéric Heitzmann
+
+test_description='git svn dcommit --interactive series'
+. ./lib-git-svn.sh
+
+test_expect_success 'initialize repo' '
+	svn_cmd mkdir -m"mkdir test-interactive" "$svnrepo/test-interactive" &&
+	git svn clone "$svnrepo/test-interactive" test-interactive &&
+	cd test-interactive &&
+	touch foo && git add foo && git commit -m"foo: first commit" &&
+	git svn dcommit
+	'
+
+test_expect_success 'answers: y [\n] yes' '
+	(
+		echo "change #1" >> foo && git commit -a -m"change #1" &&
+		echo "change #2" >> foo && git commit -a -m"change #2" &&
+		echo "change #3" >> foo && git commit -a -m"change #3" &&
+		( echo "y
+
+y" | GIT_SVN_NOTTY=1 git svn dcommit --interactive ) &&
+		test $(git rev-parse HEAD) = $(git rev-parse remotes/git-svn)
+	)
+	'
+
+test_expect_success 'answers: yes yes no' '
+	(
+		echo "change #1" >> foo && git commit -a -m"change #1" &&
+		echo "change #2" >> foo && git commit -a -m"change #2" &&
+		echo "change #3" >> foo && git commit -a -m"change #3" &&
+		( echo "yes
+yes
+no" | GIT_SVN_NOTTY=1 git svn dcommit --interactive ) &&
+		test $(git rev-parse HEAD^^^) = $(git rev-parse remotes/git-svn) &&
+		git reset --hard remotes/git-svn
+	)
+	'
+
+test_expect_success 'answers: yes quit' '
+	(
+		echo "change #1" >> foo && git commit -a -m"change #1" &&
+		echo "change #2" >> foo && git commit -a -m"change #2" &&
+		echo "change #3" >> foo && git commit -a -m"change #3" &&
+		( echo "yes
+quit" | GIT_SVN_NOTTY=1 git svn dcommit --interactive ) &&
+		test $(git rev-parse HEAD^^^) = $(git rev-parse remotes/git-svn) &&
+		git reset --hard remotes/git-svn
+	)
+	'
+
+test_expect_success 'answers: all' '
+	(
+		echo "change #1" >> foo && git commit -a -m"change #1" &&
+		echo "change #2" >> foo && git commit -a -m"change #2" &&
+		echo "change #3" >> foo && git commit -a -m"change #3" &&
+		( echo "all" | GIT_SVN_NOTTY=1 git svn dcommit --interactive ) &&
+		test $(git rev-parse HEAD) = $(git rev-parse remotes/git-svn) &&
+		git reset --hard remotes/git-svn
+	)
+	'
+
+test_done