Linting dynamic

(cherry picked from commit 60244e258a)

game/scripts/cds.rpy

@@ -1,5 +1,14 @@
 python early hide:
     import inspect
+
+    try:
+        from renpy.lint import python_builtins, renpy_builtins
+    except ImportError:
+        import builtins
+        python_builtins = set(dir(builtins))
+        del builtins
+        renpy_builtins = set()
+
     __register_params = frozenset(inspect.signature(renpy.register_statement).parameters).difference({"name", "parse"})
     def register_decorator(cls):
         """
@@ -54,6 +63,12 @@ python early hide:
             evaled = {n: eval(e) for n, e in self.items()}
             renpy.dynamic(**evaled)
 
+        def lint(self):
+            for domain, st in (("Python", python_builtins), ("Ren'Py", renpy_builtins)):
+                inter = st.intersection(self)
+                if inter:
+                    renpy.error(f"Dynamic statement redefines one or several {domain} builtins: {', '.join(map(repr, inter))}")
+
     @register_decorator
     class chibi:
         @staticmethod