fixes #1099: instead of nothing, compile to false

"if a in []"

Author: thejh

lib/nodes.js

@@ -1340,6 +1340,7 @@ exports.In = class In extends Base
     [cmp, cnj] = if @negated then [' !== ', ' && '] else [' === ', ' || ']
     tests = for item, i in @array.base.objects
       (if i then ref else sub) + cmp + item.compile o, LEVEL_OP
+    return 'false' if tests.length is 0
     tests = tests.join cnj
     if o.level < LEVEL_OP then tests else "(#{tests})"