Merge pull request #293 from OpShin/fix/deepcopy

Copy in right places to avoid reference capturing

opshin/__main__.py

@@ -330,9 +330,7 @@ def perform_command(args):
             script_arts = PlutusContract(
                 built_code,
                 datum_type=onchain_params[0] if len(onchain_params) == 3 else None,
-                redeemer_type=onchain_params[1]
-                if len(onchain_params) == 3
-                else onchain_params[0],
+                redeemer_type=onchain_params[1 if len(onchain_params) == 3 else 0],
                 parameter_types=param_types,
                 purpose=(purpose,),
             )

opshin/rewrite/rewrite_inject_builtins.py

@@ -24,7 +24,9 @@ def visit_Module(self, node: TypedModule) -> TypedModule:
             additional_assigns.append(
                 TypedAssign(
                     targets=[TypedName(id=b.name, typ=typ, ctx=Store())],
-                    value=RawPlutoExpr(typ=typ, expr=plt.Lambda(["_"], b.value)),
+                    value=RawPlutoExpr(
+                        typ=typ, expr=plt.Lambda(["_"], deepcopy(b.value))
+                    ),
                 )
             )
         md = copy(node)

opshin/util.py

@@ -1,3 +1,5 @@
+from copy import copy, deepcopy
+
 import typing
 
 import ast
@@ -154,12 +156,12 @@ def make_pattern(structure: plt.AST) -> plt.Pattern:
         AdHocPattern = type(
             f"AdHocPattern_{sha256(structure_serialized.encode()).digest().hex()}",
             (plt.Pattern,),
-            {"compose": lambda self: structure},
+            {"compose": lambda self: deepcopy(structure)},
         )
         AdHocPattern = dataclass(AdHocPattern)
 
         _patterns_cached[structure_serialized] = AdHocPattern()
-    return _patterns_cached[structure_serialized]
+    return deepcopy(_patterns_cached[structure_serialized])
 
 
 def patternize(method):