Merge #17705: test: re-enable CLI test support by using EncodeDecimal in json.dumps()

b6f9e3576a test: re-enable CLI test support by using EncodeDecimal in json.dumps() (fanquake)

Pull request description:

  As mentioned in https://github.com/bitcoin/bitcoin/pull/17675#issuecomment-563188648.

ACKs for top commit:
  practicalswift:
    ACK b6f9e3576a assuming Travis is happy too -- diff looks correct :)
  MarcoFalke:
    > ACK b6f9e35 assuming Travis is happy too -- diff looks correct :)

Tree-SHA512: 79fa535cc1756c8ee610a3d6a316a1c4f036797d6990a5620e44985393a2e52f78450f8e0021d0a148c08705fd1ba765508464a365f9030ae0d2cacbd7a93e19

test/functional/test_framework/test_node.py

@@ -30,6 +30,7 @@ from .util import (
     rpc_url,
     wait_until,
     p2p_port,
+    EncodeDecimal,
 )
 
 BITCOIND_PROC_WAIT_TIMEOUT = 60
@@ -489,7 +490,7 @@ def arg_to_cli(arg):
     if isinstance(arg, bool):
         return str(arg).lower()
     elif isinstance(arg, dict) or isinstance(arg, list):
-        return json.dumps(arg)
+        return json.dumps(arg, default=EncodeDecimal)
     else:
         return str(arg)
 

test/functional/test_framework/util.py

@@ -190,6 +190,11 @@ def check_json_precision():
     if satoshis != 2000000000000003:
         raise RuntimeError("JSON encode/decode loses precision")
 
+def EncodeDecimal(o):
+    if isinstance(o, Decimal):
+        return str(o)
+    raise TypeError(repr(o) + " is not JSON serializable")
+
 def count_bytes(hex_string):
     return len(bytearray.fromhex(hex_string))