hush: fix shift + $0 bug; add testcase
diff --git a/shell/hush_test/hush-misc/shift.right b/shell/hush_test/hush-misc/shift.right
new file mode 100644
index 0000000..afb90be
--- /dev/null
+++ b/shell/hush_test/hush-misc/shift.right
@@ -0,0 +1,2 @@
+./shift.tests abc d e
+./shift.tests d e
diff --git a/shell/hush_test/hush-misc/shift.tests b/shell/hush_test/hush-misc/shift.tests
new file mode 100644
index 0000000..17f2c9f
--- /dev/null
+++ b/shell/hush_test/hush-misc/shift.tests
@@ -0,0 +1,6 @@
+if test $# = 0; then
+    exec "$THIS_SH" $0 abc "d e"
+fi
+echo $0 $1 $2
+shift
+echo $0 $1 $2