Re: [PATCH] Skip t3403 selftests if stdin is not a terminal

[Junio C Hamano <junkio@cox.net>]

Junio C Hamano <junkio@cox.net> writes:

> Gerrit Pape <pape@smarden.org> writes:
>
>> sh t3403-rebase-skip.sh </dev/null fails because stdin is not connected
>> to a terminal, as in the Debian autobuild environment.  This disbales
>> the test 3 and 7 in this case.
>
> Disabling these tests somehow feels as if you are shooting the
> messenger who reports breakage of the commands they try to test.
>
> Is it expected that the git Porcelainish commands involved in
> these particular tests not to work without terminal?  If not
> maybe we should fix them, not the test.

How about this instead?

-- >8 --
Fix git-am safety checks

An earlier commit cbd64af added a check that prevents "git-am"
to run without its standard input connected to a terminal while
resuming operation.  This was to catch a user error to try
feeding a new patch from its standard input while recovery.

The assumption of the check was that it is an indication that a
new patch is being fed if the standard input is not connected to
a terminal.  It is however not quite correct (the standard input
can be /dev/null if the user knows the operation does not need
any input, for example).  This broke t3403 when the test was run
with its standard input connected to /dev/null.

When git-am is given an explicit command such as --skip, there
is no reason to insist that the standard input is a terminal; we
are not going to read a new patch anyway.

Credit goes to Gerrit Pape for noticing and reporting the
problem with t3403-rebase-skip test.

---
diff --git a/git-am.sh b/git-am.sh
index d0af786..66a8e3d 100755
--- a/git-am.sh
+++ b/git-am.sh
@@ -166,10 +166,25 @@ fi
 
 if test -d "$dotest"
 then
-	if test ",$#," != ",0," || ! tty -s
-	then
-		die "previous dotest directory $dotest still exists but mbox given."
-	fi
+	case "$#,$skip$resolved" in    
+	0,*t*)
+		# Explicit resume command and we do not have file, so
+		# we are happy.
+		: ;;
+	0,)
+		# No file input but without resume parameters; catch
+		# user error to feed us a patch from standard input
+		# when there is already .dotest.  This is somewhat
+		# unreliable -- stdin could be /dev/null for example
+		# and the caller did not intend to feed us a patch but
+		# wanted to continue unattended.
+		tty -s
+		;;
+	*)
+		false
+		;;
+	esac ||
+	die "previous dotest directory $dotest still exists but mbox given."
 	resume=yes
 else
 	# Make sure we are not given --skip nor --resolved