Ensure that non-C cbor2 still works

Author: nielstron

.github/workflows/build.yml

@@ -65,7 +65,11 @@ jobs:
       uses: astral-sh/setup-uv@v6
 
     - name: Install project
-      run: uv sync --dev
+      run: |
+        uv sync --dev
+        uv run python -c "from importlib.metadata import version; print(version('cbor2'))" > .cbor2_version
+        CBOR2_VERSION=$(cat .cbor2_version)
+        CBOR2_BUILD_C_EXTENSION=0 uv pip install --no-binary cbor2 "cbor2==$CBOR2_VERSION" --force-reinstall
 
     - name: Install secp256k1-py
       run: uv pip install python-secp256k1-cardano

.gitignore

@@ -3,6 +3,7 @@ test.uplc
 venv
 .vscode
 .DS_Store
+.cbor2_version
 # Created by https://www.toptal.com/developers/gitignore/api/python,pycharm+all
 # Edit at https://www.toptal.com/developers/gitignore?templates=python,pycharm+all
 

uplc/ast.py

@@ -3,7 +3,6 @@
 import functools
 import json
 import logging
-import math
 import sys
 import typing
 from collections import defaultdict
@@ -19,7 +18,6 @@
 from bitstring import BitArray
 from frozenlist2 import frozenlist
 import nacl.exceptions
-from _cbor2 import CBOREncoder
 from pycardano.crypto.bip32 import BIP32ED25519PublicKey
 from pycardano.serialization import IndefiniteFrozenList, IndefiniteList
 from Crypto.Hash import keccak
@@ -629,7 +627,9 @@ def _int_to_bytes(x: int):
     return x.to_bytes((x.bit_length() + 7) // 8, byteorder="big")
 
 
-def default_encoder(encoder: CBOREncoder, value: Union[PlutusData, IndefiniteList]):
+def default_encoder(
+    encoder: cbor2.CBOREncoder, value: Union[PlutusData, IndefiniteList]
+):
     """A fallback function that encodes PlutusData objects"""
     if isinstance(value, IndefiniteList):
         # Currently, cbor2 doesn't support indefinite list, therefore we need special