Add unittests for anti fee snipping for wallets

bitcoinlib/wallets.py

@@ -109,7 +109,7 @@ def wallet_exists(wallet, db_uri=None, db_password=None):
 def wallet_create_or_open(
         name, keys='', owner='', network=None, account_id=0, purpose=None, scheme='bip32', sort_keys=True,
         password='', witness_type=None, encoding=None, multisig=None, sigs_required=None, cosigner_id=None,
-        key_path=None, db_uri=None, db_cache_uri=None, db_password=None):
+        key_path=None, anti_fee_snipping=True, db_uri=None, db_cache_uri=None, db_password=None):
     """
     Create a wallet with specified options if it doesn't exist, otherwise just open
 
@@ -124,7 +124,8 @@ def wallet_create_or_open(
     else:
         return Wallet.create(name, keys, owner, network, account_id, purpose, scheme, sort_keys,
                              password, witness_type, encoding, multisig, sigs_required, cosigner_id,
-                             key_path, db_uri=db_uri, db_cache_uri=db_cache_uri, db_password=db_password)
+                             key_path, anti_fee_snipping, db_uri=db_uri, db_cache_uri=db_cache_uri,
+                             db_password=db_password)
 
 
 def wallet_delete(wallet, db_uri=None, force=False, db_password=None):
@@ -1195,7 +1196,7 @@ def create(cls, name, keys=None, owner='', network=None, account_id=0, purpose=0
             * All keys must be hardened, except for change, address_index or cosigner_id
             * Max length of path is 8 levels
         :type key_path: list, str
-        :param anti_fee_snipping: Set default locktime in transactions as current block height + 1  to avoid fee-snipping. Default is True
+        :param anti_fee_snipping: Set default locktime in transactions as current block height + 1  to avoid fee-snipping. Default is True, which will make the network more secure. You could disable it to avoid transaction fingerprinting.
         :type anti_fee_snipping: boolean
         :param db_uri: URI of the database for wallets, wallet transactions and keys
         :type db_uri: str

tests/test_wallets.py

@@ -2266,6 +2266,24 @@ def test_wallet_transaction_replace_by_fee(self):
         self.assertTrue(t2.replace_by_fee)
         self.assertEqual(t2.inputs[0].sequence, SEQUENCE_REPLACE_BY_FEE)
 
+    def test_wallet_anti_fee_snipping(self):
+        w = wallet_create_or_open('antifeesnippingtestwallet', network='testnet', anti_fee_snipping=True,
+                                  db_uri=self.database_uri)
+        w.utxo_add(w.get_key().address, 1234567, os.urandom(32).hex(), 1)
+        t = w.send_to('tb1qrjtz22q59e76mhumy0p586cqukatw5vcd0xvvz', 123456)
+        block_height = Service(network='testnet').blockcount()
+        self.assertEqual(t.locktime, block_height+1)
+
+        w2 = wallet_create_or_open('antifeesnippingtestwallet2', network='testnet', anti_fee_snipping=True)
+        w2.utxo_add(w2.get_key().address, 1234567, os.urandom(32).hex(), 1)
+        t = w2.send_to('tb1qrjtz22q59e76mhumy0p586cqukatw5vcd0xvvz', 123456, locktime=1901070183)
+        self.assertEqual(t.locktime, 1901070183)
+
+        w3 = wallet_create_or_open('antifeesnippingtestwallet3', network='testnet', anti_fee_snipping=False)
+        w3.utxo_add(w3.get_key().address, 1234567, os.urandom(32).hex(), 1)
+        t = w3.send_to('tb1qrjtz22q59e76mhumy0p586cqukatw5vcd0xvvz', 123456)
+        self.assertEqual(t.locktime, 0)
+
     @classmethod
     def tearDownClass(cls):
         del cls.wallet