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chanicpanic · Jun 29, 2024 · 4c1507a · 4c1507a
1 parent 50a8a14
commit 4c1507a
Showing 1 changed file with 4 additions and 1 deletion.
diff --git a/lark/parsers/earley.py b/lark/parsers/earley.py
@@ -300,7 +300,10 @@ def parse(self, lexer, start):
 
         if self.Tree is not None:
             # Perform our SPPF -> AST conversion
-            transformer = ForestToParseTree(self.Tree, self.callbacks, self.forest_sum_visitor and self.forest_sum_visitor(), self.resolve_ambiguity, not self.resolve_ambiguity)
+            # Disable the ForestToParseTree cache when ambiguity='resolve'
+            # to prevent a tree construction bug. See issue #1283
+            use_cache = not self.resolve_ambiguity
+            transformer = ForestToParseTree(self.Tree, self.callbacks, self.forest_sum_visitor and self.forest_sum_visitor(), self.resolve_ambiguity, use_cache)
             solutions = [transformer.transform(s) for s in solutions]
 
             if len(solutions) > 1: