send-email: do not barf when Term::ReadLine does not like your terminal

As long as we do not need to readline from the terminal, we
should not barf when starting up the program.  Without this
patch, t9001 test on Cygwin occasionally died with the following
error message:

Unable to get Terminal Size. The TIOCGWINSZ ioctl didn't work. The COLUMNS and LINES environment variables didn't work. The resize program didn't work. at /usr/lib/perl5/vendor_perl/5.8/cygwin/Term/ReadKey.pm line 362.
Compilation failed in require at /usr/lib/perl5/vendor_perl/5.8/Term/ReadLine/Perl.pm line 58.

Acked-by: Ryan Anderson <ryan@michonline.com>
Signed-off-by: Junio C Hamano <junkio@cox.net>

git-send-email.perl

@@ -22,6 +22,17 @@ use Term::ReadLine;
 use Getopt::Long;
 use Data::Dumper;
 
+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;
+
 # most mail servers generate the Date: header, but not all...
 $ENV{LC_ALL} = 'C';
 use POSIX qw/strftime/;
@@ -46,7 +57,12 @@ my $smtp_server;
 # Example reply to:
 #$initial_reply_to = ''; #<20050203173208.GA23964@foobar.com>';
 
-my $term = new Term::ReadLine 'git-send-email';
+my $term = eval {
+	new Term::ReadLine 'git-send-email';
+};
+if ($@) {
+	$term = new FakeTerm "$@: going non-interactive";
+}
 
 # Begin by accumulating all the variables (defined above), that we will end up
 # needing, first, from the command line:

t/t9001-send-email.sh

@@ -25,10 +25,13 @@ test_expect_success \
      git add fake.sendmail
      GIT_AUTHOR_NAME="A" git commit -a -m "Second."'
 
-test_expect_success \
-    'Extract patches and send' \
-    'git format-patch -n HEAD^1
-     git send-email -from="Example <nobody@example.com>" --to=nobody@example.com --smtp-server="$(pwd)/fake.sendmail" ./0001*txt'
+test_expect_success 'Extract patches' '
+    patches=`git format-patch -n HEAD^1`
+'
+
+test_expect_success 'Send patches' '
+     git send-email -from="Example <nobody@example.com>" --to=nobody@example.com --smtp-server="$(pwd)/fake.sendmail" $patches 2>errors
+'
 
 cat >expected <<\EOF
 !nobody@example.com!