failure in feature_bip68_sequence.py #27129

https://cirrus-ci.com/task/5552802257174528?logs=ci#L3998

 node0 2023-02-16T16:55:28.505405Z [httpworker.3] [rpc/request.cpp:179] [parse] [rpc] ThreadRPCServer method=sendrawtransaction user=__cookie__ 
 node0 2023-02-16T16:55:28.506156Z [httpworker.3] [txmempool.cpp:644] [check] [mempool] Checking mempool with 58 transactions and 123 inputs 
 test  2023-02-16T16:55:28.513000Z TestFramework (ERROR): JSONRPC error 
                                   Traceback (most recent call last):
                                     File "/tmp/cirrus-ci-build/ci/scratch/build/bitcoin-x86_64-pc-linux-gnu/test/functional/test_framework/test_framework.py", line 134, in main
                                       self.run_test()
                                     File "/tmp/cirrus-ci-build/ci/scratch/build/bitcoin-x86_64-pc-linux-gnu/test/functional/feature_bip68_sequence.py", line 73, in run_test
                                       self.test_sequence_lock_unconfirmed_inputs()
                                     File "/tmp/cirrus-ci-build/ci/scratch/build/bitcoin-x86_64-pc-linux-gnu/test/functional/feature_bip68_sequence.py", line 225, in test_sequence_lock_unconfirmed_inputs
                                       tx1 = self.wallet.send_self_transfer(from_node=self.nodes[0])["tx"]
                                     File "/tmp/cirrus-ci-build/ci/scratch/build/bitcoin-x86_64-pc-linux-gnu/test/functional/test_framework/wallet.py", line 249, in send_self_transfer
                                       self.sendrawtransaction(from_node=from_node, tx_hex=tx['hex'])
                                     File "/tmp/cirrus-ci-build/ci/scratch/build/bitcoin-x86_64-pc-linux-gnu/test/functional/test_framework/wallet.py", line 356, in sendrawtransaction
                                       txid = from_node.sendrawtransaction(hexstring=tx_hex, maxfeerate=maxfeerate, **kwargs)
                                     File "/tmp/cirrus-ci-build/ci/scratch/build/bitcoin-x86_64-pc-linux-gnu/test/functional/test_framework/coverage.py", line 49, in __call__
                                       return_val = self.auth_service_proxy_instance.__call__(*args, **kwargs)
                                     File "/tmp/cirrus-ci-build/ci/scratch/build/bitcoin-x86_64-pc-linux-gnu/test/functional/test_framework/authproxy.py", line 146, in __call__
                                       raise JSONRPCException(response['error'], status)
                                   test_framework.authproxy.JSONRPCException: bad-txns-premature-spend-of-coinbase, tried to spend coinbase at depth 7 (-26)
 test  2023-02-16T16:55:28.514000Z TestFramework (DEBUG): Closing down network thread 
 test  2023-02-16T16:55:28.564000Z TestFramework (INFO): Stopping nodes 
 test  2023-02-16T16:55:28.564000Z TestFramework.node0 (DEBUG): Stopping node 

Maybe due to the miniwallet change?

@MarcoFalke I think so, because send_self_transfer will call create_self_transfer which will call get_utxo (since we're not specifying it). get_utxo will return the largest utxo and it's usually the coinbase one (50). However, coinbase transactions need 100 confs and get_utxo doesn't check it what may be causing a "bad-txns-premature-spend-of-coinbase" error.

perhaps a fix:

diff --git a/test/functional/feature_bip68_sequence.py b/test/functional/feature_bip68_sequence.py
index 894afffc7..b248f2f5a 100755
--- a/test/functional/feature_bip68_sequence.py
+++ b/test/functional/feature_bip68_sequence.py
@@ -222,7 +222,8 @@ class BIP68Test(BitcoinTestFramework):
 
         # Create a mempool tx.
         self.wallet.rescan_utxos()
-        tx1 = self.wallet.send_self_transfer(from_node=self.nodes[0])["tx"]
+        utxo = utxo = self.wallet.get_utxos(include_immature_coinbase=False)[0]
+        tx1 = self.wallet.send_self_transfer(from_node=self.nodes[0], utxo_to_spend=utxo)["tx"]
         tx1.rehash()
 
         # Anyone-can-spend mempool tx.