refactor: add shim for PyObject_CallOneArg

Author: Xmader

include/pyshim.hh

@@ -118,4 +118,14 @@ static inline void _Py_SET_SIZE(PyVarObject *ob, Py_ssize_t size) {
 #define Py_SET_SIZE(ob, size) _Py_SET_SIZE((PyVarObject *)(ob), size)
 #endif
 
+/**
+ * @brief Shim for `PyObject_CallOneArg`.
+ *        `PyObject_CallOneArg` is not available in Python < 3.9
+ */
+#if PY_VERSION_HEX < 0x03090000 // Python version is less than 3.9
+inline PyObject *PyObject_CallOneArg(PyObject *func, PyObject *arg) {
+  return PyObject_CallFunction(func, "O", arg);
+}
+#endif
+
 #endif // #ifndef PythonMonkey_py_version_shim_

src/ExceptionType.cc

@@ -19,7 +19,9 @@
 #include <jsapi.h>
 #include <js/Exception.h>
 
+#include <Python.h>
 #include <frameobject.h>
+#include "include/pyshim.hh"
 
 
 PyObject *ExceptionType::getPyObject(JSContext *cx, JS::HandleObject error) {
@@ -29,11 +31,7 @@ PyObject *ExceptionType::getPyObject(JSContext *cx, JS::HandleObject error) {
   PyObject *errStr = getExceptionString(cx, JS::ExceptionStack(cx, errValue, errStack), true);
 
   // Construct a new SpiderMonkeyError python object
-  #if PY_VERSION_HEX >= 0x03090000
   PyObject *pyObject = PyObject_CallOneArg(SpiderMonkeyError, errStr); // _PyErr_CreateException, https://github.com/python/cpython/blob/3.9/Python/errors.c#L100
-  #else
-  PyObject *pyObject = PyObject_CallFunction(SpiderMonkeyError, "O", errStr); // PyObject_CallOneArg is not available in Python < 3.9
-  #endif
   Py_XDECREF(errStr);
 
   // Preserve the original JS Error object as the Python Exception's `jsError` attribute for lossless two-way conversion

src/IntType.cc

@@ -14,6 +14,9 @@
 #include <jsapi.h>
 #include <js/BigInt.h>
 
+#include <Python.h>
+#include "include/pyshim.hh"
+
 #include <vector>
 
 #define SIGN_BIT_MASK 0b1000 // https://hg.mozilla.org/releases/mozilla-esr102/file/tip/js/src/vm/BigIntType.h#l40
@@ -98,11 +101,7 @@ PyObject *IntType::getPyObject(JSContext *cx, JS::BigInt *bigint) {
   // Cast to a pythonmonkey.bigint to differentiate it from a normal Python int,
   //  allowing Py<->JS two-way BigInt conversion.
   // We don't do `Py_SET_TYPE` because `_PyLong_FromByteArray` may cache and reuse objects for small ints
-  #if PY_VERSION_HEX >= 0x03090000
   PyObject *pyObject = PyObject_CallOneArg(getPythonMonkeyBigInt(), pyIntObj); // pyObject = pythonmonkey.bigint(pyIntObj)
-  #else
-  PyObject *pyObject = PyObject_CallFunction(getPythonMonkeyBigInt(), "O", pyIntObj); // PyObject_CallOneArg is not available in Python < 3.9
-  #endif
   Py_DECREF(pyIntObj);
 
   // Set the sign bit

src/PromiseType.cc

@@ -19,6 +19,9 @@
 #include <jsfriendapi.h>
 #include <js/Promise.h>
 
+#include <Python.h>
+#include "include/pyshim.hh"
+
 // slot ids to access the python object in JS callbacks
 #define PY_FUTURE_OBJ_SLOT 0
 #define PROMISE_OBJ_SLOT 1
@@ -38,11 +41,7 @@ static bool onResolvedCb(JSContext *cx, unsigned argc, JS::Value *vp) {
   if (state == JS::PromiseState::Rejected && !PyExceptionInstance_Check(result)) {
     // Wrap the result object into a SpiderMonkeyError object
     // because only *Exception objects can be thrown in Python `raise` statement and alike
-    #if PY_VERSION_HEX >= 0x03090000
     PyObject *wrapped = PyObject_CallOneArg(SpiderMonkeyError, result); // wrapped = SpiderMonkeyError(result)
-    #else
-    PyObject *wrapped = PyObject_CallFunction(SpiderMonkeyError, "O", result); // PyObject_CallOneArg is not available in Python < 3.9
-    #endif
     // Preserve the original JS value as the `jsError` attribute for lossless conversion back
     PyObject *originalJsErrCapsule = DictType::getPyObject(cx, resultArg);
     PyObject_SetAttrString(wrapped, "jsError", originalJsErrCapsule);