git-am: Don't accept an mbox on stdin of we already have a .dotest directory

It makes no sense to accept an mbox via stdin when we
won't accept it on the commandline.

The patch helps the following scenario:

# git init-db
"add file1 with content"
# git checkout -b apply
"edit file1 && commit"

# git checkout -b conflict master
"edit file1 && commit"

# git checkout -b ok master
"add file2"

# git checkout apply
# git format-patch -k -3 master..conflict | git am -k -3
=> git-am fails with a conflict message
# git reset --hard

# git format-patch -k -3 master..ok | git am -k -3
=> git am fails with the same conflict message as above,
=> since it's trying to apply the old .dotest directory

With the patch it complains about an old .dotest
directory instead.

Signed-off-by: Lukas Sandström <lukass@etek.chalmers.se>
Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/git-am.sh b/git-am.sh
index 3a129e0021f4847ac6f717a97b69b5a399088c99..04f01194356ea0c91a01eed682b068c15e313ee6 100755 (executable)
--- a/git-am.sh
+++ b/git-am.sh
@@ -156,8 +156,10 @@ fi
 
 if test -d "$dotest"
 then
-       test ",$#," = ",0," ||
-       die "previous dotest directory $dotest still exists but mbox given."
+       if test ",$#," != ",0," || ! tty -s
+       then
+               die "previous dotest directory $dotest still exists but mbox given."
+       fi
        resume=yes
 else
        # Make sure we are not given --skip nor --resolved