test, refactor: Add TestNode.binaries to hold binary paths

Add new TestNode.binaries object to manage paths to bitcoin binaries.

Having this object makes it possible for the test framework to exercise the
bitcoin wrapper executable introduced in
https://github.com/bitcoin/bitcoin/pull/31375 and also makes it easier to add
new binaries and options and environment variables controlling how they are
invoked, because logic for invoking them that was previously spread out is now
consolidated in one place.

Co-authored-by: Sjors Provoost <sjors@sprovoost.nl>

test/functional/test_framework/test_node.py

@@ -76,7 +76,7 @@ class TestNode():
     To make things easier for the test writer, any unrecognised messages will
     be dispatched to the RPC connection."""
 
-    def __init__(self, i, datadir_path, *, chain, rpchost, timewait, timeout_factor, bitcoind, bitcoin_cli, coverage_dir, cwd, extra_conf=None, extra_args=None, use_cli=False, start_perf=False, use_valgrind=False, version=None, descriptors=False, v2transport=False):
+    def __init__(self, i, datadir_path, *, chain, rpchost, timewait, timeout_factor, binaries, coverage_dir, cwd, extra_conf=None, extra_args=None, use_cli=False, start_perf=False, use_valgrind=False, version=None, descriptors=False, v2transport=False):
         """
         Kwargs:
             start_perf (bool): If True, begin profiling the node with `perf` as soon as
@@ -92,7 +92,7 @@ class TestNode():
         self.chain = chain
         self.rpchost = rpchost
         self.rpc_timeout = timewait
-        self.binary = bitcoind
+        self.binaries = binaries
         self.coverage_dir = coverage_dir
         self.cwd = cwd
         self.descriptors = descriptors
@@ -109,8 +109,7 @@ class TestNode():
         # Configuration for logging is set as command-line args rather than in the bitcoin.conf file.
         # This means that starting a bitcoind using the temp dir to debug a failed test won't
         # spam debug.log.
-        self.args = [
-            self.binary,
+        self.args = self.binaries.daemon_argv() + [
             f"-datadir={self.datadir_path}",
             "-logtimemicros",
             "-debug",
@@ -149,7 +148,7 @@ 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(bitcoin_cli, self.datadir_path)
+        self.cli = TestNodeCLI(binaries, self.datadir_path)
         self.use_cli = use_cli
         self.start_perf = start_perf
 
@@ -870,16 +869,16 @@ def arg_to_cli(arg):
 
 class TestNodeCLI():
     """Interface to bitcoin-cli for an individual node"""
-    def __init__(self, binary, datadir):
+    def __init__(self, binaries, datadir):
         self.options = []
-        self.binary = binary
+        self.binaries = binaries
         self.datadir = datadir
         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.binary, self.datadir)
+        cli = TestNodeCLI(self.binaries, self.datadir)
         cli.options = [str(o) for o in options]
         cli.input = input
         return cli
@@ -900,7 +899,7 @@ class TestNodeCLI():
         """Run bitcoin-cli command. Deserializes returned string as python object."""
         pos_args = [arg_to_cli(arg) for arg in args]
         named_args = [str(key) + "=" + arg_to_cli(value) for (key, value) in kwargs.items()]
-        p_args = [self.binary, f"-datadir={self.datadir}"] + self.options
+        p_args = self.binaries.rpc_argv() + [f"-datadir={self.datadir}"] + self.options
         if named_args:
             p_args += ["-named"]
         if clicommand is not None:
@@ -916,7 +915,7 @@ class TestNodeCLI():
                 code, message = match.groups()
                 raise JSONRPCException(dict(code=int(code), message=message))
             # Ignore cli_stdout, raise with cli_stderr
-            raise subprocess.CalledProcessError(returncode, self.binary, output=cli_stderr)
+            raise subprocess.CalledProcessError(returncode, p_args, output=cli_stderr)
         try:
             return json.loads(cli_stdout, parse_float=decimal.Decimal)
         except (json.JSONDecodeError, decimal.InvalidOperation):