Bugfix for deepcopy + small unrelated refactor (issue #938)

lark/common.py

@@ -1,4 +1,5 @@
 from warnings import warn
+from copy import deepcopy
 
 from .utils import Serialize
 from .lexer import TerminalDef
@@ -31,6 +32,17 @@ class LexerConf(Serialize):
     def _deserialize(self):
         self.terminals_by_name = {t.name: t for t in self.terminals}
 
+    def __deepcopy__(self, memo=None):
+        return type(self)(
+            deepcopy(self.terminals, memo),
+            self.re_module,
+            deepcopy(self.ignore, memo),
+            deepcopy(self.postlex, memo),
+            deepcopy(self.callbacks, memo),
+            deepcopy(self.g_regex_flags, memo),
+            deepcopy(self.skip_validation, memo),
+            deepcopy(self.use_bytes, memo),
+        )
 
 
 class ParserConf(Serialize):

lark/utils.py

@@ -73,14 +73,13 @@ class Serialize(object):
         fields = getattr(self, '__serialize_fields__')
         res = {f: _serialize(getattr(self, f), memo) for f in fields}
         res['__type__'] = type(self).__name__
-        postprocess = getattr(self, '_serialize', None)
-        if postprocess:
-            postprocess(res, memo)
+        if hasattr(self, '_serialize'):
+            self._serialize(res, memo)
         return res
 
     @classmethod
     def deserialize(cls, data, memo):
-        namespace = getattr(cls, '__serialize_namespace__', {})
+        namespace = getattr(cls, '__serialize_namespace__', [])
         namespace = {c.__name__:c for c in namespace}
 
         fields = getattr(cls, '__serialize_fields__')
@@ -94,9 +93,10 @@ class Serialize(object):
                 setattr(inst, f, _deserialize(data[f], namespace, memo))
             except KeyError as e:
                 raise KeyError("Cannot find key for class", cls, e)
-        postprocess = getattr(inst, '_deserialize', None)
-        if postprocess:
-            postprocess()
+
+        if hasattr(inst, '_deserialize'):
+            inst._deserialize()
+
         return inst