refactor: Set TestNode.cli only after RPC is connected

The cli can only be called after the RPC is connected, so the cli field
should only be set after that. This is similar to the _rpc field.

This change has also other benefits:

* Manually overwriting the cli with a new rpchost is no longer needed,
  so one cli-specific line can be removed from the rpc_bind.py test.
* The datadir and rpc_timeout fields are removed from the TestNodeCLI
  struct. They were redundant with the -datadir and -rpcclienttimeout
  command line options. Any command line option can be overwritten by
  appending it with a new value, if needed.

test/functional/rpc_bind.py

@@ -39,7 +39,6 @@ class RPCBindTest(BitcoinTestFramework):
             base_args += ['-rpcallowip=' + x for x in allow_ips]
         binds = ['-rpcbind='+addr for addr in addresses]
         self.nodes[0].rpchost = connect_to
-        self.nodes[0].cli = self.nodes[0].create_new_rpc_connection(mode="CLI")  # Pass `connect_to` to cli.
         self.start_node(0, base_args + binds)
         pid = self.nodes[0].process.pid
         assert_equal(set(get_bind_addrs(pid)), set(expected))

test/functional/test_framework/test_node.py

@@ -189,11 +189,7 @@ class TestNode():
                 self.args.append("-v2transport=0")
         # if v2transport is requested via global flag but not supported for node version, ignore it
 
-        self.cli = TestNodeCLI(
-            binaries,
-            self.datadir_path,
-            self.rpc_timeout // 2,  # timeout identical to the one used in self._rpc
-        )
+        self.cli = None
         self.use_cli = use_cli
         self.start_perf = start_perf
 
@@ -328,7 +324,12 @@ class TestNode():
             rpc.auth_service_proxy_instance.reuse_http_connections = self.reuse_http_connections
             return rpc
         else:  # mode==CLI
-            return self.cli(f"-rpcclienttimeout={client_timeout}", f"-rpcconnect={host}", f"-rpcport={port}")
+            return TestNodeCLI(self.binaries)(
+                f"-datadir={self.datadir_path}",
+                f"-rpcclienttimeout={client_timeout}",
+                f"-rpcconnect={host}",
+                f"-rpcport={port}",
+            )
 
     def wait_for_rpc_connection(self, *, wait_for_import=True):
         """Sets up an RPC connection to the bitcoind process. Returns False if unable to connect."""
@@ -378,6 +379,7 @@ class TestNode():
                 self.log.debug("RPC successfully started")
                 # Set rpc_connected even if we are in use_cli mode so that we know we can call self.stop() if needed.
                 self.rpc_connected = True
+                self.cli = self.create_new_rpc_connection(mode="CLI")
                 if self.use_cli:
                     return
                 self._rpc = rpc
@@ -977,18 +979,16 @@ def arg_to_cli(arg):
 
 class TestNodeCLI():
     """Interface to bitcoin-cli for an individual node"""
-    def __init__(self, binaries, datadir, rpc_timeout):
+    def __init__(self, binaries):
         self.options = []
         self.binaries = binaries
-        self.datadir = datadir
-        self.rpc_timeout = rpc_timeout
         self.input = None
         self.log = logging.getLogger('TestFramework.bitcoincli')
 
     def __call__(self, *options, input=None):
         # TestNodeCLI is callable with bitcoin-cli command-line options
-        cli = TestNodeCLI(self.binaries, self.datadir, self.rpc_timeout)
-        cli.options = [str(o) for o in options]
+        cli = TestNodeCLI(self.binaries)
+        cli.options = self.options + [str(o) for o in options]
         cli.input = input
         return cli
 
@@ -1008,10 +1008,7 @@ class TestNodeCLI():
         """Run bitcoin-cli command. Deserializes returned string as python object."""
         pos_args = [arg_to_cli(arg) for arg in args]
         named_args = [key + "=" + arg_to_cli(value) for (key, value) in kwargs.items() if value is not None]
-        p_args = self.binaries.rpc_argv() + [
-            f"-datadir={self.datadir}",
-            f"-rpcclienttimeout={int(self.rpc_timeout)}",
-        ] + self.options
+        p_args = self.binaries.rpc_argv() + self.options
         if named_args:
             p_args += ["-named"]
         base_arg_pos = len(p_args)

test/functional/tool_signet_miner.py

@@ -69,7 +69,7 @@ class SignetMinerTest(BitcoinTestFramework):
         n_blocks = node.getblockcount()
         base_dir = self.config["environment"]["SRCDIR"]
         signet_miner_path = os.path.join(base_dir, "contrib", "signet", "miner")
-        rpc_argv = node.binaries.rpc_argv() + [f"-datadir={node.cli.datadir}"]
+        rpc_argv = node.binaries.rpc_argv() + [f"-datadir={node.datadir_path}"]
         util_argv = node.binaries.util_argv() + ["grind"]
         subprocess.run([
                 sys.executable,
@@ -89,7 +89,7 @@ class SignetMinerTest(BitcoinTestFramework):
         n_blocks = node.getblockcount()
         base_dir = self.config["environment"]["SRCDIR"]
         signet_miner_path = os.path.join(base_dir, "contrib", "signet", "miner")
-        rpc_argv = node.binaries.rpc_argv() + [f"-datadir={node.cli.datadir}"]
+        rpc_argv = node.binaries.rpc_argv() + [f"-datadir={node.datadir_path}"]
         util_argv = node.binaries.util_argv() + ["grind"]
         base_cmd = [
             sys.executable,