test: Allow pathlib.Path as RPC argument via authproxy

Also, add datadir_path property to TestNode

test/functional/test_framework/test_node.py

@@ -22,7 +22,10 @@ import shlex
 import sys
 from pathlib import Path
 
-from .authproxy import JSONRPCException
+from .authproxy import (
+    JSONRPCException,
+    EncodeDecimal,
+)
 from .descriptors import descsum_create
 from .p2p import P2P_SUBVERSION
 from .util import (
@@ -35,7 +38,6 @@ from .util import (
     rpc_url,
     wait_until_helper,
     p2p_port,
-    EncodeDecimal,
 )
 
 BITCOIND_PROC_WAIT_TIMEOUT = 60
@@ -405,9 +407,13 @@ class TestNode():
         with open(self.bitcoinconf, 'w', encoding='utf8') as conf:
             conf.write(conf_data)
 
+    @property
+    def datadir_path(self) -> Path:
+        return Path(self.datadir)
+
     @property
     def chain_path(self) -> Path:
-        return Path(self.datadir) / self.chain
+        return self.datadir_path / self.chain
 
     @property
     def debug_log_path(self) -> Path: