From 16c2e13fb48c3e7cdab945310280766e12e2f260 Mon Sep 17 00:00:00 2001
From: Kittywhiskers Van Gogh <63189531+kwvg@users.noreply.github.com>
Date: Mon, 16 Dec 2024 08:31:46 +0000
Subject: [PATCH] test: add functional tests for `coinjoinsalt` RPC

---
 test/functional/rpc_coinjoin.py | 73 +++++++++++++++++++++++++++++++++
 test/functional/test_runner.py  |  2 -
 2 files changed, 73 insertions(+), 2 deletions(-)

diff --git a/test/functional/rpc_coinjoin.py b/test/functional/rpc_coinjoin.py
index 8ca9c865fa..70f9955377 100755
--- a/test/functional/rpc_coinjoin.py
+++ b/test/functional/rpc_coinjoin.py
@@ -3,13 +3,17 @@
 # Distributed under the MIT software license, see the accompanying
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
+import random
+
 from test_framework.test_framework import BitcoinTestFramework
 from test_framework.messages import (
     COIN,
     MAX_MONEY,
+    uint256_to_string,
 )
 from test_framework.util import (
     assert_equal,
+    assert_is_hex_string,
     assert_raises_rpc_error,
 )
 
@@ -36,9 +40,22 @@ class CoinJoinTest(BitcoinTestFramework):
 
         node.createwallet(wallet_name='w1', blank=True, disable_private_keys=False)
         w1 = node.get_wallet_rpc('w1')
+        self.test_salt_presence(w1)
         self.test_coinjoin_start_stop(w1)
         self.test_setcoinjoinamount(w1)
         self.test_setcoinjoinrounds(w1)
+        self.test_coinjoinsalt(w1)
+        w1.unloadwallet()
+
+        node.createwallet(wallet_name='w2', blank=True, disable_private_keys=True)
+        w2 = node.get_wallet_rpc('w2')
+        self.test_coinjoinsalt_disabled(w2)
+        w2.unloadwallet()
+
+    def test_salt_presence(self, node):
+        self.log.info('Salt should be automatically generated in new wallet')
+        # Will raise exception if no salt generated
+        assert_is_hex_string(node.coinjoinsalt('get'))
 
     def test_coinjoin_start_stop(self, node):
         self.log.info('"coinjoin" subcommands should update mixing status')
@@ -81,5 +98,61 @@ class CoinJoinTest(BitcoinTestFramework):
         for value in [COINJOIN_ROUNDS_MIN - 1, COINJOIN_ROUNDS_MAX + 1]:
             assert_raises_rpc_error(-8, "Invalid number of rounds", node.setcoinjoinrounds, value)
 
+    def test_coinjoinsalt(self, node):
+        self.log.info('"coinjoinsalt generate" should fail if salt already present')
+        assert_raises_rpc_error(-32600, 'Wallet "w1" already has set CoinJoin salt!', node.coinjoinsalt, 'generate')
+
+        self.log.info('"coinjoinsalt" subcommands should succeed if no balance and not mixing')
+        # 'coinjoinsalt generate' should return a new salt if overwrite enabled
+        s1 = node.coinjoinsalt('get')
+        assert_equal(node.coinjoinsalt('generate', True), True)
+        s2 = node.coinjoinsalt('get')
+        assert s1 != s2
+
+        # 'coinjoinsalt get' should fetch newly generated value (i.e. new salt should persist)
+        node.unloadwallet('w1')
+        node.loadwallet('w1')
+        node = self.nodes[0].get_wallet_rpc('w1')
+        assert_equal(s2, node.coinjoinsalt('get'))
+
+        # 'coinjoinsalt set' should work with random hashes
+        s1 = uint256_to_string(random.getrandbits(256))
+        node.coinjoinsalt('set', s1)
+        assert_equal(s1, node.coinjoinsalt('get'))
+        assert s1 != s2
+
+        # 'coinjoinsalt set' shouldn't work with nonsense values
+        s2 = format(0, '064x')
+        assert_raises_rpc_error(-8, "Invalid CoinJoin salt value", node.coinjoinsalt, 'set', s2, True)
+        s2 = s2[0:63] + 'h'
+        assert_raises_rpc_error(-8, "salt must be hexadecimal string (not '%s')" % s2, node.coinjoinsalt, 'set', s2, True)
+
+        self.log.info('"coinjoinsalt generate" and "coinjoinsalt set" should fail if mixing')
+        # Start mix session
+        node.coinjoin('start')
+        assert_equal(node.getcoinjoininfo()['running'], True)
+
+        # 'coinjoinsalt generate' and 'coinjoinsalt set' should fail when mixing
+        assert_raises_rpc_error(-4, 'Wallet "w1" is currently mixing, cannot change salt!', node.coinjoinsalt, 'generate', True)
+        assert_raises_rpc_error(-4, 'Wallet "w1" is currently mixing, cannot change salt!', node.coinjoinsalt, 'set', s1, True)
+
+        # 'coinjoinsalt get' should still work
+        assert_equal(node.coinjoinsalt('get'), s1)
+
+        # Stop mix session
+        node.coinjoin('stop')
+        assert_equal(node.getcoinjoininfo()['running'], False)
+
+        # 'coinjoinsalt generate' and 'coinjoinsalt set' should start working again
+        assert_equal(node.coinjoinsalt('generate', True), True)
+        assert_equal(node.coinjoinsalt('set', s1, True), True)
+
+    def test_coinjoinsalt_disabled(self, node):
+        self.log.info('"coinjoinsalt" subcommands should fail if private keys disabled')
+        for subcommand in ['generate', 'get']:
+            assert_raises_rpc_error(-32600, 'Wallet "w2" has private keys disabled, cannot perform CoinJoin!', node.coinjoinsalt, subcommand)
+        s1 = uint256_to_string(random.getrandbits(256))
+        assert_raises_rpc_error(-32600, 'Wallet "w2" has private keys disabled, cannot perform CoinJoin!', node.coinjoinsalt, 'set', s1)
+
 if __name__ == '__main__':
     CoinJoinTest().main()
diff --git a/test/functional/test_runner.py b/test/functional/test_runner.py
index 2b311fca34..e1c2b7680a 100755
--- a/test/functional/test_runner.py
+++ b/test/functional/test_runner.py
@@ -892,8 +892,6 @@ class RPCCoverage():
         # Consider RPC generate covered, because it is overloaded in
         # test_framework/test_node.py and not seen by the coverage check.
         covered_cmds = set({'generate'})
-        # TODO: implement functional tests for coinjoinsalt
-        covered_cmds.add('coinjoinsalt')
         # TODO: implement functional tests for voteraw
         covered_cmds.add('voteraw')
         # TODO: implement functional tests for getmerkleblocks