Added tests checking ability of the scripting engine to reorder the output of...

Added tests checking ability of the scripting engine to reorder the output of commands with a random output regarding signle elements position in the multi bulk reply.

tests/unit/scripting.tcl

@@ -190,6 +190,30 @@ start_server {tags {"scripting"}} {
             [r script load "return 'loaded'"] \
             [r evalsha b534286061d4b9e4026607613b95c06c06015ae8 0]
     } {b534286061d4b9e4026607613b95c06c06015ae8 loaded}
+
+    test "In the context of Lua the output of random commands gets ordered" {
+        r del myset
+        r sadd myset a b c d e f g h i l m n o p q r s t u v z aa aaa azz
+        r eval {return redis.call('smembers','myset')} 0
+    } {a aa aaa azz b c d e f g h i l m n o p q r s t u v z}
+
+    test "SORT is normally not re-ordered by the scripting engine" {
+        r del myset
+        r sadd myset 1 2 3 4 10
+        r eval {return redis.call('sort','myset','desc')} 0
+    } {10 4 3 2 1}
+
+    test "SORT BY <constant> output gets ordered by scripting" {
+        r del myset
+        r sadd myset a b c d e f g h i l m n o p q r s t u v z aa aaa azz
+        r eval {return redis.call('sort','myset','by','_')} 0
+    } {a aa aaa azz b c d e f g h i l m n o p q r s t u v z}
+
+    test "SORT output containing NULLs is well handled by scripting" {
+        r del myset
+        r sadd myset a b c
+        r eval {return redis.call('sort','myset','by','_','get','#','get','_:*')} 0
+    } {{} {} {} a b c}
 }
 
 start_server {tags {"scripting repl"}} {