test: Remove 0.16.3 test from wallet_backwards_compatibility.py #30920

The test checks that any wallet created with current master can not be loaded with v0.16.3. This is interesting documentation, however it is probably not something to keep as a test, because:

• It seems like an extremely unlikely (and unsupported) edge case that someone creates a wallet with master and then goes ahead to open it with a long EOL software version.
• A better test would be the inverse: Create a wallet with v0.16.3 and open it with current master. This is already tested in wallet_upgradewallet.py, where I've added an additional balance check before upgrading the v0.16.3 wallet.
• The test is intermittently failing when shutting down the v0.16.3 node, for example in #30875 (comment). The exact cause is unclear, but given that the test isn't worthy to keep, removing it will ensure that the error disappears.

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Conflicts

No conflicts as of last run.

was there a seed value for #30875 (comment)?

I'm trying to look for it to try and reproduce but am having trouble finding it

[edit] never mind I was able to get the full logs to open up seed:8381474046628750392

I'm trying to look for it to try and reproduce but am having trouble finding it

I think the logs were nuked in the meantime, which is a Cirrus bug :(

IIRC it may have been a shutdown error of the v0.16.3 software. However, I don't think looking at the CI failure matters, because the test doesn't make much sense and a more realistic test already exists.

cc @Sjors from 89a28e02fa46f3d5eb07ab02aa34aa95c6fcee11

Since we can longer create a legacy (bdb4) wallets and since older Bitcoin Core versions can't load descriptor (sqlite3) wallets, it should be safe to drop certain older nodes from the downgrade tests.

Will study this PR later.

I keep seeing the shutdown bug, also locally:

 test  2024-10-03T15:31:32.242000Z TestFramework (INFO): Test that wallets created in master are too new for 0.16 
 test  2024-10-03T15:31:32.242000Z TestFramework.node11 (DEBUG): Stopping node 
 test  2024-10-03T15:31:32.340000Z TestFramework (ERROR): Unexpected exception caught during testing 
                                   Traceback (most recent call last):
                                     File "/ci_container_base/test/functional/test_framework/test_framework.py", line 132, in main
                                       self.run_test()
                                     File "/ci_container_base/ci/scratch/build-x86_64-pc-linux-gnu/test/functional/wallet_backwards_compatibility.py", line 295, in run_test
                                       self.stop_node(node_v16.index)
                                     File "/ci_container_base/test/functional/test_framework/test_framework.py", line 581, in stop_node
                                       self.nodes[i].stop_node(expected_stderr, wait=wait)
                                     File "/ci_container_base/test/functional/test_framework/test_node.py", line 397, in stop_node
                                       self.stop()
                                     File "/ci_container_base/test/functional/test_framework/coverage.py", line 50, in __call__
                                       return_val = self.auth_service_proxy_instance.__call__(*args, **kwargs)
                                     File "/ci_container_base/test/functional/test_framework/authproxy.py", line 127, in __call__
                                       response, status = self._request('POST', self.__url.path, postdata.encode('utf-8'))
                                     File "/ci_container_base/test/functional/test_framework/authproxy.py", line 106, in _request
                                       return self._get_response()
                                     File "/ci_container_base/test/functional/test_framework/authproxy.py", line 164, in _get_response
                                       http_response = self.__conn.getresponse()
                                     File "/usr/lib/python3.10/http/client.py", line 1375, in getresponse
                                       response.begin()
                                     File "/usr/lib/python3.10/http/client.py", line 318, in begin
                                       version, status, reason = self._read_status()
                                     File "/usr/lib/python3.10/http/client.py", line 287, in _read_status
                                       raise RemoteDisconnected("Remote end closed connection without"
                                   http.client.RemoteDisconnected: Remote end closed connection without response

with the node log:

                                   2024-10-03 15:31:32.250748 Stopping RPC
                                   2024-10-03 15:31:32.250913 RPC stopped.
                                   2024-10-03 15:31:32.250936 Stopping HTTP server
                                   2024-10-03 15:31:32.250948 Waiting for HTTP worker threads to exit
                                   2024-10-03 15:31:32.251430 addcon thread exit
                                   2024-10-03 15:31:32.251520 Waiting for HTTP event thread to exit
                                   2024-10-03 15:31:32.259012 msghand thread exit
                                   2024-10-03 15:31:32.262571 Exited http event loop
                                   2024-10-03 15:31:32.337592 Stopped HTTP server
                                   2024-10-03 15:31:32.337684 CDBEnv::Flush: Flush(false)
                                   2024-10-03 15:31:32.337703 CDBEnv::Flush: Flush(false) took               0ms
                                   2024-10-03 15:31:32.337716 CDBEnv::Flush: Flush(false)
                                   2024-10-03 15:31:32.337728 CDBEnv::Flush: Flush(false) took               0ms
                                   2024-10-03 15:31:32.338399 net thread exit
                                   2024-10-03 15:31:32.342600 Flushed 0 addresses to peers.dat  1ms
                                   2024-10-03 15:31:32.356145 scheduler thread interrupt
                                   2024-10-03 15:31:32.356809 Dumped mempool: 5e-06s to copy, 0.000187s to dump
                                   2024-10-03 15:31:32.356856 Recorded 1 unconfirmed txs from mempool in 1.6e-05s
                                   2024-10-03 15:31:32.358456 Writing final batch of 0.01 MiB
                                   2024-10-03 15:31:32.358594 Committed 106 changed transaction outputs (out of 106) to coin database...
                                   2024-10-03 15:31:32.359266 Writing final batch of 0.00 MiB
                                   2024-10-03 15:31:32.359301 Committed 0 changed transaction outputs (out of 0) to coin database...
                                   2024-10-03 15:31:32.359404 CDBEnv::Flush: Flush(true)
                                   2024-10-03 15:31:32.359425 CDBEnv::Flush: Flushing 0 (refcount = 0)...
                                   2024-10-03 15:31:32.359457 CDBEnv::Flush: 0 checkpoint
                                   2024-10-03 15:31:32.359545 CDBEnv::Flush: 0 detach
                                   2024-10-03 15:31:32.359675 CDBEnv::Flush: 0 closed
                                   2024-10-03 15:31:32.359697 CDBEnv::Flush: Flushing wallet.dat (refcount = 0)...
                                   2024-10-03 15:31:32.359721 CDBEnv::Flush: wallet.dat checkpoint
                                   2024-10-03 15:31:32.359781 CDBEnv::Flush: wallet.dat detach
                                   2024-10-03 15:31:32.359884 CDBEnv::Flush: wallet.dat closed
                                   2024-10-03 15:31:32.359901 CDBEnv::Flush: Flush(true) took               0ms
                                   2024-10-03 15:31:32.542072 CDBEnv::Flush: Flush(true) database not started
                                   2024-10-03 15:31:32.542401 Shutdown: done

utACK fae44c83da982095661b034bdd01afe8ac2fb0a6

ACK fae44c83da982095661b034bdd01afe8ac2fb0a6 - I agree that test seems to have past it's usefulness, and the fact that it otherwise causes intemittent issues is further reason to remove it.