sh: Add test for obscure and ambiguous ${#?}.

Obtained-from: FreeBSD

diff --git a/tools/regression/bin/sh/expansion/length4.0 b/tools/regression/bin/sh/expansion/length4.0
new file mode 100644 (file)
index 0000000..4f1fa3e
--- /dev/null
+++ b/tools/regression/bin/sh/expansion/length4.0
@@ -0,0 +1,11 @@
+# $FreeBSD: src/tools/regression/bin/sh/expansion/length4.0,v 1.1 2011/04/15 15:26:05 jilles Exp $
+
+# The construct ${#?} is ambiguous in POSIX.1-2008: it could be the length
+# of $? or it could be $# giving an error in the (impossible) case that it
+# is not set.
+# We use the former interpretation; it seems more useful.
+
+:
+[ "${#?}" = 1 ] || echo '${#?} wrong'
+(exit 42)
+[ "${#?}" = 2 ] || echo '${#?} wrong'