Fix running languages.test on sh/bash.

tests/languages.test

@@ -2,7 +2,7 @@
 
 # Test a command for presence and ability to output the sha1 hash of a file.
 check_hashcmd() {
-	which $1 >&/dev/null &&
+	which $1 &>/dev/null &&
 	$1 </dev/null 2>/dev/null |
 	awk '{if ($1 != "da39a3ee5e6b4b0d3255bfef95601890afd80709") { exit 1; }}'
 }
@@ -16,7 +16,7 @@ elif check_hashcmd shasum; then
 	sha1sum=shasum
 else
 	echo "No hashing commands found."
-	false
+	exit 1
 fi
 
 test_lang() {