Implement JSON send/recv test case

tests.py

@@ -3,9 +3,10 @@ from os import stat, urandom
 from os.path import exists, dirname, realpath, join
 from stat import S_ISFIFO
 from secrets import token_urlsafe
-from random import randint
+from random import randint, getrandbits, uniform
 from threading import Thread
 from contextlib import contextmanager
+from json import dumps, loads
 
 import pytest
 
@@ -157,3 +158,24 @@ def test_io_newlines(io_pipes):
     io_pipes.send(b'\n' * times)
     for _ in range(times + 1):  # IOPipes.send appends +1
         assert io_pipes.recv() == b''
+
+
+def test_json_io(io_pipes):
+    for _ in range(10):
+        test_data = {
+            f'{token_urlsafe(8)}': randint(1, 2 ** 20),
+            f'{token_urlsafe(9)}': [randint(1, 2 **10) for i in range(10)],
+            f'{token_urlsafe(4)}': f'{token_urlsafe(8)}\\\n{token_urlsafe(8)}\n{randint(1, 2 ** 10)}',
+            f'{token_urlsafe(11)}': {
+                f'{token_urlsafe(8)}': '',
+                f'{token_urlsafe(3)}': f'{token_urlsafe(8)}\n{token_urlsafe(8)}\n\\n{token_urlsafe(8)}',
+                f'{token_urlsafe(44)}': f'{token_urlsafe(8)}\n{token_urlsafe(8)}  {token_urlsafe(8)}',
+                f'{token_urlsafe(6)}\n{token_urlsafe(4)}': bool(getrandbits(1)),
+                f'{token_urlsafe(8)}': None,
+                f'{token_urlsafe(21)}  {token_urlsafe(4)}': None,
+                f'{token_urlsafe(3)}': uniform(randint(1, 100), randint(1, 100)),
+                f'{token_urlsafe(8)}': [token_urlsafe(4) for i in range(10)],
+            }
+        }
+        io_pipes.send(dumps(test_data).encode())
+        assert loads(io_pipes.recv()) == test_data