If a node has not announced a tx at all, then it should respond to
getdata messages for that tx with notfound, to avoid leaking tx
origination privacy.
Adds a generate() method to the TestNode class in the test framework.
This method intercepts calls to generate, imports a dewterministic
private key to the node and then calls generatetoaddress to generate the
block to that address.
Note that repeated calls to importprivkey for the same private keys are
no-ops, so it's fine to call the generate() method many times.
faa4043c66 qa: Run more tests with wallet disabled (MarcoFalke)
Pull request description:
Instead of skipping the whole test, only skip the wallet specific section of a test if the wallet is not compiled in. This is mostly an indentation change, so can be reviewed with `--ignore-all-space`.
Tree-SHA512: 5941a8b6b00dca5cf9438c5f6f010ba812115188a69e427d7ade4c1ab8cfe7a57c73daf52c66235dbb24b1cd9ab7c7a17c49bc23d931e041b605d79116a71f66
a2a04a5abb Bugfix: Only run bitcoin-tx tests when bitcoin-tx is enabled (Luke Dashjr)
92af71cea9 configure: Make it possible to build only one of bitcoin-cli or bitcoin-tx (Luke Dashjr)
Pull request description:
Includes #5618 (which the reasons for rejecting no longer hold true)
Tree-SHA512: f30a8e4a2f70166b7cabef77c4674163b3a9da14c6a547d34f00d1056a19bf4d23e22851eea726fad2afc8735d5473ae91122c770b65ac3886663dc20e2c5b70
e460232876 Document fixed attribute behavior in critical test framework classes. (Justin Turner Arthur)
17b42f4122 Check for specific tx acceptance failures based on script signature (Justin Turner Arthur)
3a4449e9ad Strictly enforce instance attrs in critical functional test classes. (Justin Turner Arthur)
1d0ce94a54 Fix for incorrect version attr set on functional test segwit block. (Justin Turner Arthur)
ba923e32a0 test: Fix broken segwit test (practicalswift)
Pull request description:
No extra attributes will be able to be added to instances of the C++ class ports or of other critical classes without causing an exception. Helps prevent adding or depending on attributes that aren't in the intended object structure. It may prevent issues such as the one fixed in bitcoin/bitcoin#14300.
This request fixes the erroneous version attribute used in the p2p_segwit.py functional tests. This pull includes the commit from bitcoin/bitcoin#14300.
Tree-SHA512: 1b8c58e7aa0f71075ed5ff3e5be0a5182599108d8cd9bce682feac3b1842508124288e9335432b16a43f40f159c9710899e6d84af1b5868f48c947bc6f3e07ec
661ac15a4a appveyor: Run functional tests on appveyor (Chun Kuan Lee)
2148c36b6e tests: Make it possible to run functional tests on Windows (Chun Kuan Lee)
Pull request description:
This PR do the following things:
- Make functional tests compatible with Windows
- Print color output in functional tests for Windows 10
- Run util and functional tests on appveyor
- Do not run symlink tests on Windows
Note:
- The wallet_multiwallet.py fail is unrelated to the test framework, it's a bug related to c++ code or maybe dependencies. `bitcoind` would exit with 0xC0000005(Access violation) during shutdown occasionally. Disable this for now.
- Not using `--failfast` because this is still in experimental. We should track if there is any other error.
- Disable ZMQ tests because the python zmq library could cause access violation sometimes.
- Disable `feature_notifications` because Bitcoin Core handles the command in different thread, whicha can cause a race condition.
Tree-SHA512: b76db137d264e62a5c130e1cbca7a2ca002a7a0f4153fa0b92c1ea6c9c09ef0533e11c49bdbd566c472d8ff59f245758feb5e5a6ec6cb6bb66a1c67bab5fa48a
c1dde3a949 No longer shutdown after encrypting the wallet (Andrew Chow)
d7637c5a3f After encrypting the wallet, reload the database environment (Andrew Chow)
5d296ac810 Add function to close all Db's and reload the databae environment (Andrew Chow)
a769461d5e Move BerkeleyEnvironment deletion from internal method to callsite (Andrew Chow)
Pull request description:
This is the replacement for #11678 which implements @ryanofsky's [suggestion](https://github.com/bitcoin/bitcoin/pull/11678#pullrequestreview-76464511).
Shutting down the software was to prevent the BDB environment from writing unencrypted private keys to disk in the database log files, as was noted [here](https://bitcointalk.org/index.php?topic=51474.msg616068#msg616068). This PR replaces the shutdown behavior with a CDBEnv flush, close, and reopen which achieves the same effect: everything is cleanly flushed and closed, the log files are removed, and then the environment reopened to continue normal operation.
To ensure that no unencrypted private keys are in the log files after encrypting the wallet, I wrote [this script](https://gist.github.com/achow101/7f7143e6c3d3fdc034d3470e72823e9d) to pull private keys from the original wallet file and searches for these keys in the log files (note that you will have to change your file paths to make it work on your own machine).
As for concerns about private keys being written to slack space or being kept in memory, these behaviors no longer exist after the original wallet encryption PR and the shutting down solution from 2011.
cc @ryanofsky
Tree-SHA512: 34b894283b0677a873d06dee46dff8424dec85a2973009ac9b84bcf3d22d05f227c494168c395219d9aee3178e420cf70d4b3eeacc9785aa86b6015d25758e75
fa8433e379 qa: Remove unneded import_deterministic_coinbase_privkeys overwrite, add comments (MarcoFalke)
e413c2ddd1 qa: Fix codespell error and have lint-spelling error instead of warn (MarcoFalke)
Pull request description:
Currently the functional tests require the wallet module to be compiled into the Bitcoin Core executable. For example the premine (or datadir cache) to speed up tests when run in parallel would mine a bunch of blocks and store the private keys to sign the coinbase tx outputs in a wallet. There is no need to have the overhead of the whole wallet module by using keys that are deterministic for all runs.
Note that this change most likely requires the `./test/cache/` to be cleared.
Tree-SHA512: 9ce26036b0e10f0f888f66a1e50be6a357343f9ffb302ae24a7bb3df2f083a31702ef308b738a03b08a1b623aeddac5d6563dc1b15078c0357b7dafad7808ec3
fac9539836 qa: Run all tests even if wallet is not compiled (MarcoFalke)
faa669cbcd qa: Premine to deterministic address with -disablewallet (MarcoFalke)
Pull request description:
Currently the test_runner would exit if the wallet was not compiled into the Bitcoin Core executable. However, a lot of the tests run without the wallet just fine and there is no need to globally require the wallet to run the tests.
Tree-SHA512: 63177260aa29126fd20f0be217a82b10b62288ab846f96f1cbcc3bd2c52702437703475d91eae3f8d821a3149fc62b725a4c5b2a7b3657b67ffcbc81532a03bb
fac3e22b18 qa: Read reject reasons from debug log, not p2p messages (MarcoFalke)
Pull request description:
For local testing we don't need to rely on p2p messages just to assert a reject reason.
Replace reading p2p messages with reading from the debug log file.
Tree-SHA512: fa59598ecf5e00cfb420ef1892d90aa415501fd882e1c608894dc577b0d00e93a442326d3a9167fef77d26aafbe345b730b49109982ccad68a5942384564a90b
68400d8b96 tests: Use explicit imports (practicalswift)
Pull request description:
Enable automatic detection of undefined names in Python tests scripts. Remove wildcard imports.
Wildcard imports make it unclear which names are present in the namespace, confusing both readers and many automated tools.
An additional benefit of not using wildcard imports in tests scripts is that readers of a test script then can infer the rough testing scope just by looking at the imports.
Before this commit:
```
$ contrib/devtools/lint-python.sh | head -10
./test/functional/feature_rbf.py:8:1: F403 'from test_framework.util import *' used; unable to detect undefined names
./test/functional/feature_rbf.py:9:1: F403 'from test_framework.script import *' used; unable to detect undefined names
./test/functional/feature_rbf.py:10:1: F403 'from test_framework.mininode import *' used; unable to detect undefined names
./test/functional/feature_rbf.py:15:12: F405 bytes_to_hex_str may be undefined, or defined from star imports: test_framework.mininode, test_framework.script, test_framework.util
./test/functional/feature_rbf.py:17:58: F405 CScript may be undefined, or defined from star imports: test_framework.mininode, test_framework.script, test_framework.util
./test/functional/feature_rbf.py:25:13: F405 COIN may be undefined, or defined from star imports: test_framework.mininode, test_framework.script, test_framework.util
./test/functional/feature_rbf.py:26:31: F405 satoshi_round may be undefined, or defined from star imports: test_framework.mininode, test_framework.script, test_framework.util
./test/functional/feature_rbf.py:26:60: F405 COIN may be undefined, or defined from star imports: test_framework.mininode, test_framework.script, test_framework.util
./test/functional/feature_rbf.py:30:41: F405 satoshi_round may be undefined, or defined from star imports: test_framework.mininode, test_framework.script, test_framework.util
./test/functional/feature_rbf.py:30:68: F405 COIN may be undefined, or defined from star imports: test_framework.mininode, test_framework.script, test_framework.util
$
```
After this commit:
```
$ contrib/devtools/lint-python.sh | head -10
$
```
Tree-SHA512: 3f826d39cffb6438388e5efcb20a9622ff8238247e882d68f7b38609877421b2a8e10e9229575f8eb6a8fa42dec4256986692e92922c86171f750a0e887438d9
cf9ed307e6 qa: blocktools enforce named args for amount (MarcoFalke)
Pull request description:
Since #13669 changed some signatures, I think it might be worthwhile to enforce named args for primitive types such as amounts.
Tree-SHA512: 2733e7b6a20590b54bd54e81a09e3f5e2fadf4390bed594916b70729bcf485b048266012c1203369e0968032a2c6a2719107ac17ee925d8939af3df916eab1a6
fafe73a626 qa: Raise feature_help timeout to 5s (MarcoFalke)
faabd7bc47 qa: Use files for stdout/stderr to support Windows (MarcoFalke)
facb56ffaf qa: Run gen_rpcauth with sys.executable (MarcoFalke)
fada8966c5 qa: Close stdout and stderr file when node stops (MarcoFalke)
Pull request description:
### qa: Close stdout and stderr file when node stops
Since these files are potentially deleted by the test framework for cleanup, they should be closed first. Otherwise this will lead to errors on Windows when the tests finish successfully.
Side note: After the patch, it is no longer possible to reopen the file on Windows (see https://docs.python.org/3/library/tempfile.html#tempfile.NamedTemporaryFile)
### qa: Run gen_rpcauth with sys.executable
Similar to `test_runner.py`, the `sys.executable` needs to be passed down into subprocesses to pass on native Windows. (Should have no effect on Linux)
### qa: Use files for stdout/stderr to support Windows
It seems that using PIPE is not supported on Windows. Also, it is easier to just use the files that capture the stdout and stderr within the test node class.
Tree-SHA512: ec675012b10705978606b7fcbdb287c39a8e6e3732aae2fa4041d963a3c6993c6eac6a9a3cbd5479514e7d8017fe74c12235d1ed6fed2e8af8f3c71981e91864
fa85c985ed qa: Add p2p_invalid_locator test (MarcoFalke)
Pull request description:
Should not be merged *before* #13907
Tree-SHA512: a67ca407854c421ed20a184d0b0dc90085aed3e3431d9652a107fa3022244767e67f67e50449b7e95721f56906836b134615875f28a21e8a012eb22cfe6a66a5
fa5587fe71 qa: wait_for_verack by default (MarcoFalke)
Pull request description:
This removes the need to do so manually every time a connection is added.
Tree-SHA512: a46c92cb4df41e30778b42b9fd3dcbd8d2d82aa7503d1213cb1c1165034f648d8caee01c292e2d87d05b0f71696996eef5be8a753f35ab49e5f66b0e3bf29f21
3fc20632a3 qt: Set BLOCK_CHAIN_SIZE = 220 (DrahtBot)
2b6a2f4a28 Regenerate manpages (DrahtBot)
eb7daf4d60 Update copyright headers to 2018 (DrahtBot)
Pull request description:
Some trivial maintenance to avoid having to do it again after the 0.17 branch off.
(The scripts to do this are in `./contrib/`)
Tree-SHA512: 16b2af45e0351b1c691c5311d48025dc6828079e98c2aa2e600dc5910ee8aa01858ca6c356538150dc46fe14c8819ed8ec8e4ec9a0f682b9950dd41bc50518fa
fa67505e1e qa: Quote wallet name for rpc path (MarcoFalke)
Pull request description:
When using external multiwallets they are specified by their full path which might contain non-ascii characters (e.g. umlauts or emojis).
Fix this by url-quoting the path.
Tree-SHA512: 7cc66514579d9f602f88a6817c5ab43a44c6d3711df452dc904173f0bc34e2c0b2c34877497f06b61f6720c532fa183053f54622dc454e316c89cee7eaa72463
https://github.com/bitcoin/bitcoin/pull/13715 introduced a new check
for _transport.is_closing() in mininode's P2PConnection's. This function
is only available from Python 3.4.4, though, while Bitcoin is supposed
to support all Python 3.4 versions.
In this change, we make the check conditional on is_closing() being
available. If it is not, then we revert to the behaviour before the
check was introduced; this means that
https://github.com/bitcoin/bitcoin/issues/13579 is not fixed for old
systems, but at least the tests work as they used to do before.
This includes a small refactoring from a one-line lambda to an
inline function, because this makes the code easier to read with more
and more conditions being added.
Fixes https://github.com/bitcoin/bitcoin/issues/13745.
fa4bf92be9 Remove dead service bits code (MarcoFalke)
Pull request description:
Seems fine to remove for the upcoming 0.17 release
Fixes#10993
Tree-SHA512: 3a4664b787e3da399bcaaba693619bd384826df14f469dbdfbbfffc540d9da3f2b322cda262b43388376785f77907c2540541c239ab0fca82bd7eb69d02b6b7a
a3fa4d6a6a QA: Fix bug in -usecli logic that converts booleans to non-lowercase strings (Jonas Schnelli)
4704e5f074 [QA] add createwallet disableprivatekey test (Jonas Schnelli)
c7b8f343e9 [Qt] Disable creating receive addresses when private keys are disabled (Jonas Schnelli)
2f15c2bc20 Add disable privatekeys option to createwallet (Jonas Schnelli)
cebefba085 Add option to disable private keys during internal wallet creation (Jonas Schnelli)
9995a602a6 Add facility to store wallet flags (64 bits) (Jonas Schnelli)
Pull request description:
This mode ('createwallet {"disableprivatekeys": true}') is intended for a sane pure watch-only mode, ideal for a use-case where one likes to use Bitcoin-Core in conjunction with a hardware-wallet or another solutions for cold-storage.
Since we have support for custom change addresses in `fundrawtransaction`, pure watch-only wallets including coin-selection are possible and do make sense for some use cases.
This new mode disables all forms of private key generation and ensure that no mix between hot and cold keys are possible.
Tree-SHA512: 3ebe7e8d54c4d4e5f790c348d4c292d456f573960a5b04d69ca5ef43a9217c7e7671761c6968cdc56f9a8bc235f3badd358576651af9f10855a0eb731f3fc508
d280617bf5 [qa] Add a test for merkle proof malleation (Suhas Daftuar)
ed82f17000 have verifytxoutproof check the number of txns in proof structure (Gregory Sanders)
Pull request description:
Recent publication of a weakness in Bitcoin's merkle tree construction demonstrates many SPV applications vulnerable to an expensive to pull off yet still plausible attack: https://bitslog.wordpress.com/2018/06/09/leaf-node-weakness-in-bitcoin-merkle-tree-design/
This change would at least allow `verifytxoutproof` to properly validate that the proof matches a known block, with known number of transactions any time after the full block is processed. This should neuter the attack entirely.
The negative is that a header-only processed block/future syncing mode would cause this to fail until the node has imported the data required.
related: #13451
`importprunedfunds` needs this check as well. Can expand it to cover this if people like the idea.
Tree-SHA512: 0682ec2b622a38b29f3f635323e0a8b6fc071e8a6fd134c954579926ee7b516e642966bafa667016744ce49c16e19b24dbc8801f982a36ad0a6a4aff6d93f82b
09c6699900 [qa] Handle disconnect_node race (Suhas Daftuar)
Pull request description:
Several tests call disconnect_nodes() on each node-pair in rapid
succession, resulting in a race condition if a node disconnects a peer
in-between the calculation of the nodeid's to disconnect and the
invocation of the disconnectnode rpc call. Handle this.
Tree-SHA512: 3078cea0006fcb507c812004a777c505eb1e9dda7c6df12dbbe72395a73ff6f6760f597b6492054f5487b34534417ddef5fbad30553c135c288c4b7cfce79223
Several tests call disconnect_nodes() on each node-pair in rapid
succession, resulting in a race condition if a node disconnects a peer
in-between the calculation of the nodeid's to disconnect and the
invocation of the disconnectnode rpc call. Handle this.
By default, libc will print fatal errors to /dev/tty instead of stderr.
Adding the LIBC_FATAL_STDERR_ to the environment variables allows
us to catch libc errors in stderr and test for them.
fac1e1f qa: Remove unused option --srcdir (MarcoFalke)
Pull request description:
The `srcdir` option was both unused and misleading; It should have been called `builddir`. So remove it.
Tree-SHA512: 2c24dcf2aa82219158b8cbbf03dd3f0f51f805f1f5f670faa1fd59e5a8d60fda120ffddadeccb058d8d3f20583b4952be7afd2df6bbefb9367d35c0f0a9fda3c
891beb0 [test] fundrawtransaction: lock watch-only shared address (Karl-Johan Alm)
Pull request description:
`self.nodes[0]` creates an address which is watch-only-shared with `self.nodes[3]`. If `nodes[0]` spends the associated UTXO during any of its sends later, the watchonly test will fail, as `nodes[3]` now has insufficient funds.
I ran into this in #12257 and this commit is in that PR as well, but I figured I'd split it out (and remove from there once/if merged).
Tree-SHA512: d04a04b1ecebe82127cccd47c1b3de311bf07f4b51dff80db20ea2f142e1d5c4a85ed6180c5c0b081d550e238c742e119b953f60f487deac5a3f3536e1a8d9fe
fa811b0 qa: Normalize executable location (MarcoFalke)
Pull request description:
This removes the need to override the executable locations by just reading them from the config file. Beside making the code easier to read, running individual test on Windows is now possible by default (without providing further command line arguments).
Note: Of course, it is still possible to manually specify the location through the `BITCOIND` environment variable, e.g. `bitcoin-qt`.
Tree-SHA512: bee6d22246796242d747120ca18aaab089f73067de213c9111182561985c5912228a0b0f7f9eec025ecfdb44db031f15652f30d67c489d481c995bb3232a7ac7
80a5e59 [qa] Attach node index to test_node AssertionError and print messages (James O'Beirne)
Pull request description:
In the midst of fighting with https://github.com/bitcoin/bitcoin/pull/12873 it became apparent that there're a number of assertions and print statements which are emitted by test nodes but don't identify the node in question. This change makes debugging a bit easier by adding identifying information to non-logger test_node-related error messages.
Tree-SHA512: 7cc86f2c81f4b3fdba15ec9a2d21a84c4b083629e845e82288087c3affbbdc5c68e74067621856cc97fe84fbc8cb4f5ca4977a51ef381e5d74515df8eb001239
c25321f Add config changes to release notes (Anthony Towns)
5e3cbe0 [tests] Unit tests for -testnet/-regtest in [test]/[regtest] sections (Anthony Towns)
005ad26 ArgsManager: special handling for -regtest and -testnet (Anthony Towns)
608415d [tests] Unit tests for network-specific config entries (Anthony Towns)
68797e2 ArgsManager: Warn when ignoring network-specific config setting (Anthony Towns)
d1fc4d9 ArgsManager: limit some options to only apply on mainnet when in default section (Anthony Towns)
8a9817d [tests] Use regtest section in functional tests configs (Anthony Towns)
30f9407 [tests] Unit tests for config file sections (Anthony Towns)
95eb66d ArgsManager: support config file sections (Anthony Towns)
4d34fcc ArgsManager: drop m_negated_args (Anthony Towns)
3673ca3 ArgsManager: keep command line and config file arguments separate (Anthony Towns)
Pull request description:
The weekly meeting on [2017-12-07](http://www.erisian.com.au/meetbot/bitcoin-core-dev/2017/bitcoin-core-dev.2017-12-07-19.00.log.html) discussed allowing options to bitcoin to have some sensitivity to what network is in use. @theuni suggested having sections in the config file:
<cfields> an alternative to that would be sections in a config file. and on the
cmdline they'd look like namespaces. so, [testnet] port=5. or -testnet::port=5.
This approach is (more or less) supported by `boost::program_options::detail::config_file_iterator` -- when it sees a `[testnet]` section with `port=5`, it will treat that the same as "testnet.port=5". So `[testnet] port=5` (or `testnet.port=5` without the section header) in bitcoin.conf and `-testnet.port=5` on the command line.
The other aspect to this question is possibly limiting some options so that there is no possibility of accidental cross-contamination across networks. For example, if you're using a particular wallet.dat on mainnet, you may not want to accidentally use the same wallet on testnet and risk reusing keys.
I've set this up so that the `-addnode` and `-wallet` options are `NETWORK_ONLY`, so that if you have a bitcoin.conf:
wallet=/secret/wallet.dat
upnp=1
and you run `bitcoind -testnet` or `bitcoind -regtest`, then the `wallet=` setting will be ignored, and should behave as if your bitcoin.conf had specified:
upnp=1
[main]
wallet=/secret/wallet.dat
For any `NETWORK_ONLY` options, if you're using `-testnet` or `-regtest`, you'll have to add the prefix to any command line options. This was necessary for `multiwallet.py` for instance.
I've left the "default" options as taking precedence over network specific ones, which might be backwards. So if you have:
maxmempool=200
[regtest]
maxmempool=100
your maxmempool will still be 200 on regtest. The advantage of doing it this way is that if you have `[regtest] maxmempool=100` in bitcoin.conf, and then say `bitcoind -regtest -maxmempool=200`, the same result is probably in line with what you expect...
The other thing to note is that I'm using the chain names from `chainparamsbase.cpp` / `ChainNameFromCommandLine`, so the sections are `[main]`, `[test]` and `[regtest]`; not `[mainnet]` or `[testnet]` as might be expected.
Thoughts? Ping @MeshCollider @laanwj @jonasschnelli @morcos
Tree-SHA512: f00b5eb75f006189987e5c15e154a42b66ee251777768c1e185d764279070fcb7c41947d8794092b912a03d985843c82e5189871416995436a6260520fb7a4db
9db48c5634 tests: Remove redundant bytes² (practicalswift)
Pull request description:
This is a follow-up to #12993. As @jnewbery noted `bytes()` is idempotent.
Tree-SHA512: 0eb25e0c2c46f9abaac30f964c5eb422bece1414c840a717d86794424294cb19d995a6db7c8df2a2f4ec84776b05274a637f2c111738f397051f510e57184752
75d0e4c544 [qa] Delete cookie file before starting node (Suhas Daftuar)
Pull request description:
When a node is restarted during a test after an unclean shutdown (such
as with -dbcrashratio), it's possible an old cookie file was left
behind. This can cause a race condition when restarting the node, where
the test framework might try to connect using credentials from the
old cookie file, just as the node will generate new credentials and
overwrite the old file.
Delete any such cookie file if present prior to startup.
Tree-SHA512: ae1e8bf8fd20e07c32b0715025693bb28b0e3dd34f328cae4346abf579b0c97b5db1c02782e1c46b7a3b6058d268b6d46b668e847658a6eed0be857ffb0d65dc
If a cookie file exists in a datadir prior to node startup, it must have
been leftover from a prior unclean shutdown. As bitcoind will overwrite
it anyway, delete it before starting up to prevent the test framework
from inadvertently trying to connect using stale credentials.
c9cce0a Tests: Add Metaclass for BitcoinTestFramework (Will Ayd)
Pull request description:
BitcoinTestFramework instructs developers in its docstring to override
`set_test_params` and `run_test` in subclasses while being sure NOT to
override `__init__` and `main` . This change adds a metaclass to ensure
that developers adhere to that protocol, raising a ``TypeError`` in
instances where they have not.
closes#12835
Tree-SHA512: 5a47a7ead1f18361138cad4374747c4a8f29d25506f7b2c2a8c1c966a0b65e5ccf7317f9a078df8680fdab5d3fb71fee46a159c9f381878a3683c1e9f874abbe
e36a0c0 [qa] Ensure bitcoind processes are cleaned up when tests end (Suhas Daftuar)
Pull request description:
When tests fail (such as due to a bug in the test, race condition, etc), it's possible that we could follow code paths that bypass our normal node shutdown that occurs in `TestNode.stop_node`. Add a destructor to `TestNode` that cleans this up.
Tree-SHA512: 72e04bc21462ebd0cb346fd1fe0540da454acfbad41923a0b06ea2317e9045b68e58f9adb02d8200891aca89a9d03a022eb72282aeb31a3b3afe7c6843a4b450
self.nodes[0] creates an address which is watch-only-shared with self.nodes[3]. If nodes[0] spends the associated UTXO during any of its sends later, the watchonly test will fail, as nodes[3] now has insufficient funds.
Note that this also adds a new find_vout_for_address function to the test framework.
