Fix tests and pyawaitable_await_function implementation

src/_pyawaitable/awaitable.c

@@ -213,17 +213,22 @@ pyawaitable_await_function_impl(
 )
 {
     size_t len = strlen(fmt);
-    char *tup_format = PyMem_Malloc(len + 3);
+    size_t size = len + 3;
+    char *tup_format = PyMem_Malloc(size);
     if (!tup_format)
     {
         PyErr_NoMemory();
         return -1;
     }
 
     tup_format[0] = '(';
-    strcpy(tup_format + 1, fmt);
-    tup_format[len - 2] = ')';
-    tup_format[len - 1] = '\0';
+    for (size_t i = 0; i < len; ++i)
+    {
+        tup_format[i + 1] = fmt[i];
+    }
+
+    tup_format[size - 2] = ')';
+    tup_format[size - 1] = '\0';
 
     va_list vargs;
     va_start(vargs, err);
@@ -233,8 +238,8 @@ pyawaitable_await_function_impl(
 
     if (!args)
         return -1;
-
     PyObject *coro = PyObject_Call(func, args, NULL);
+    Py_DECREF(args);
 
     if (!coro)
         return -1;

tests/test_awaitable.py

@@ -76,6 +76,7 @@ class AwaitableABI(PyABI):
         ),
         ("unpack", ctypes.PYFUNCTYPE(ctypes.c_int, ctypes.py_object)),
         ("unpack_arb", ctypes.PYFUNCTYPE(ctypes.c_int, ctypes.py_object)),
+        ("PyAwaitableType", ctypes.py_object),
         ("await_function", ctypes.PYFUNCTYPE(ctypes.c_int, ctypes.py_object, ctypes.py_object, ctypes.c_char_p, awaitcallback, awaitcallback_err,)),
     ]
 
@@ -440,14 +441,19 @@ def cb(awaitable_inner: pyawaitable.PyAwaitable, result: str):
 @limit_leaks(LEAK_LIMIT)
 async def test_await_function():
     awaitable = abi.new()
+    called: bool = False
 
     async def coro(value: int, suffix: str) -> str:
         await asyncio.sleep(0)
         return str(value * 2) + suffix
 
     @awaitcallback
     def cb(awaitable_inner: pyawaitable.PyAwaitable, result: str):
+        nonlocal called
+        called = True
         assert result == "42hello"
         return 0
 
-    abi.await_function(awaitable, coro, b"is", cb, None, 21, b"hello")
+    abi.await_function(awaitable, coro, b"is", cb, awaitcallback_err(0), 21, b"hello")
+    await awaitable
+    assert called is True