Merge branch 'jk/test-match-signal' into maint

The test framework learned a new helper test_match_signal to
check an exit code from getting killed by an expected signal.

* jk/test-match-signal:
  t/lib-git-daemon: use test_match_signal
  test_must_fail: use test_match_signal
  t0005: use test_match_signal as appropriate
  tests: factor portable signal check out of t0005

t/lib-git-daemon.sh

@@ -82,8 +82,7 @@ stop_git_daemon() {
 	kill "$GIT_DAEMON_PID"
 	wait "$GIT_DAEMON_PID" >&3 2>&4
 	ret=$?
-	# expect exit with status 143 = 128+15 for signal TERM=15
-	if test $ret -ne 143
+	if test_match_signal 15 $?
 	then
 		error "git daemon exited with status: $ret"
 	fi

t/t0005-signals.sh

@@ -11,12 +11,13 @@ EOF
 
 test_expect_success 'sigchain works' '
 	{ test-sigchain >actual; ret=$?; } &&
-	case "$ret" in
-	143) true ;; # POSIX w/ SIGTERM=15
-	271) true ;; # ksh w/ SIGTERM=15
-	  3) true ;; # Windows
-	  *) false ;;
-	esac &&
+	{
+		# Signal death by raise() on Windows acts like exit(3),
+		# regardless of the signal number. So we must allow that
+		# as well as the normal signal check.
+		test_match_signal 15 "$ret" ||
+		test "$ret" = 3
+	} &&
 	test_cmp expect actual
 '
 
@@ -41,12 +42,12 @@ test_expect_success 'create blob' '
 
 test_expect_success !MINGW 'a constipated git dies with SIGPIPE' '
 	OUT=$( ((large_git; echo $? 1>&3) | :) 3>&1 ) &&
-	test "$OUT" -eq 141
+	test_match_signal 13 "$OUT"
 '
 
 test_expect_success !MINGW 'a constipated git dies with SIGPIPE even if parent ignores it' '
 	OUT=$( ((trap "" PIPE; large_git; echo $? 1>&3) | :) 3>&1 ) &&
-	test "$OUT" -eq 141
+	test_match_signal 13 "$OUT"
 '
 
 test_done

t/test-lib-functions.sh

@@ -612,7 +612,7 @@ test_must_fail () {
 	then
 		echo >&2 "test_must_fail: command succeeded: $*"
 		return 1
-	elif test $exit_code -eq 141 && list_contains "$_test_ok" sigpipe
+	elif test_match_signal 13 $exit_code && list_contains "$_test_ok" sigpipe
 	then
 		return 0
 	elif test $exit_code -gt 129 && test $exit_code -le 192
@@ -961,3 +961,18 @@ test_env () {
 		done
 	)
 }
+
+# Returns true if the numeric exit code in "$2" represents the expected signal
+# in "$1". Signals should be given numerically.
+test_match_signal () {
+	if test "$2" = "$((128 + $1))"
+	then
+		# POSIX
+		return 0
+	elif test "$2" = "$((256 + $1))"
+	then
+		# ksh
+		return 0
+	fi
+	return 1
+}