comprehensive testing for regression analysis

internal/engine.cm

@@ -1,4 +1,4 @@
-// Hidden vars (os, actorsym, init, core_path, shop_path, analyze, run_ast_fn, json) come from env
+// Hidden vars (os, actorsym, init, core_path, shop_path, analyze, run_ast_fn, run_ast_noopt_fn, json) come from env
 // In actor spawn mode, also: nota, wota
 var ACTORDATA = actorsym
 var SYSYM = '__SYSTEM__'
@@ -214,6 +214,7 @@ os.global_shop_path = shop_path
 os.$_ = $_
 os.analyze = analyze
 os.run_ast_fn = run_ast_fn
+os.run_ast_noopt_fn = run_ast_noopt_fn
 os.json = json
 use_cache['core/json'] = json