Built in some safety when running tests and there is no debug_info

interface/HUTN/hutn_compiler/compiler.py

@@ -129,7 +129,6 @@ def do_compile(inputfile, grammarfile, visitors=[], include_paths = []):
 
     result["tree"].fix_tracability(inputfile)
 
-    print 'yentl told me to print'
     for visitor in visitors:
         visitor.visit(result["tree"])
 

kernel/modelverse_kernel/main.py

@@ -149,7 +149,8 @@ class ModelverseKernel(object):
                                ("DE", [lnk]),
                                ("DN", [user_frame]),
                               ]
-        self.debug_info[self.username].pop()
+        if self.debug_info[self.username]:
+            self.debug_info[self.username].pop()
 
     ########################################
     ### Execute input and output methods ###
@@ -537,7 +538,8 @@ class ModelverseKernel(object):
                 _, =            yield [("DN", [user_root])]
                 del self.debug_info[self.username]
             else:
-                self.debug_info[self.username].pop()
+                if self.debug_info[self.username]:
+                    self.debug_info[self.username].pop()
                 _, _ =          yield [("CD", [user_root, "frame", prev_frame]),
                                        ("DN", [user_frame]),
                                       ]
@@ -560,7 +562,8 @@ class ModelverseKernel(object):
                                   ]
 
     def return_eval(self, user_root):
-        self.debug_info[self.username].pop()
+        if self.debug_info[self.username]:
+            self.debug_info[self.username].pop()
         user_frame, =       yield [("RD", [user_root, "frame"])]
         prev_frame, =       yield [("RD", [user_frame, "prev"])]
         returnvalue, old_returnvalue_link = \