Uniformize argument names of "call" functions

* Callable object: callable, o, callable_object => func
* Object for method calls: o => obj
* Method name: name or nameid => method

Cleanup also the C code:

* Don't initialize variables to NULL if they are not used before their first
  assignement
* Add braces for readability

2 files changed, 71 insertions, 68 deletions

diff --git a/Objects/abstract.c b/Objects/abstract.c
index beb12c9..1a83e93 100644
--- a/Objects/abstract.c
+++ b/Objects/abstract.c
@@ -2173,9 +2173,9 @@ PyMapping_Values(PyObject *o)
 /* XXX PyCallable_Check() is in object.c */
 
 PyObject *
-PyObject_CallObject(PyObject *o, PyObject *a)
+PyObject_CallObject(PyObject *func, PyObject *args)
 {
-    return PyEval_CallObjectWithKeywords(o, a, NULL);
+    return PyEval_CallObjectWithKeywords(func, args, NULL);
 }
 
 PyObject*
@@ -2331,10 +2331,10 @@ exit:
     return result;
 }
 
-/* Positional arguments are obj followed args. */
+/* Positional arguments are arg0 followed args: [arg0, *args]. */
 PyObject *
 _PyObject_Call_Prepend(PyObject *func,
-                       PyObject *obj, PyObject *args, PyObject *kwargs)
+                       PyObject *arg0, PyObject *args, PyObject *kwargs)
 {
     PyObject *small_stack[8];
     PyObject **stack;
@@ -2356,7 +2356,7 @@ _PyObject_Call_Prepend(PyObject *func,
     }
 
     /* use borrowed references */
-    stack[0] = obj;
+    stack[0] = arg0;
     memcpy(&stack[1],
               &PyTuple_GET_ITEM(args, 0),
               argcount * sizeof(PyObject *));
@@ -2489,34 +2489,34 @@ _PyObject_FastCallKeywords(PyObject *func, PyObject **stack, Py_ssize_t nargs,
 }
 
 static PyObject*
-call_function_tail(PyObject *callable, PyObject *args)
+call_function_tail(PyObject *func, PyObject *args)
 {
     PyObject *result;
 
     assert(args != NULL);
 
     if (!PyTuple_Check(args)) {
-        result = _PyObject_CallArg1(callable, args);
+        result = _PyObject_CallArg1(func, args);
     }
     else {
-        result = PyObject_Call(callable, args, NULL);
+        result = PyObject_Call(func, args, NULL);
     }
 
     return result;
 }
 
 PyObject *
-PyObject_CallFunction(PyObject *callable, const char *format, ...)
+PyObject_CallFunction(PyObject *func, const char *format, ...)
 {
     va_list va;
     PyObject *args, *result;
 
-    if (callable == NULL) {
+    if (func == NULL) {
         return null_error();
     }
 
     if (!format || !*format) {
-        return _PyObject_CallNoArg(callable);
+        return _PyObject_CallNoArg(func);
     }
 
     va_start(va, format);
@@ -2526,23 +2526,23 @@ PyObject_CallFunction(PyObject *callable, const char *format, ...)
         return NULL;
     }
 
-    result = call_function_tail(callable, args);
+    result = call_function_tail(func, args);
     Py_DECREF(args);
     return result;
 }
 
 PyObject *
-_PyObject_CallFunction_SizeT(PyObject *callable, const char *format, ...)
+_PyObject_CallFunction_SizeT(PyObject *func, const char *format, ...)
 {
     va_list va;
     PyObject *args, *result;
 
-    if (callable == NULL) {
+    if (func == NULL) {
         return null_error();
     }
 
     if (!format || !*format) {
-        return _PyObject_CallNoArg(callable);
+        return _PyObject_CallNoArg(func);
     }
 
     va_start(va, format);
@@ -2552,7 +2552,7 @@ _PyObject_CallFunction_SizeT(PyObject *callable, const char *format, ...)
         return NULL;
     }
 
-    result = call_function_tail(callable, args);
+    result = call_function_tail(func, args);
     Py_DECREF(args);
     return result;
 }
@@ -2589,19 +2589,20 @@ callmethod(PyObject* func, const char *format, va_list va, int is_size_t)
 }
 
 PyObject *
-PyObject_CallMethod(PyObject *o, const char *name, const char *format, ...)
+PyObject_CallMethod(PyObject *obj, const char *method, const char *format, ...)
 {
     va_list va;
     PyObject *func = NULL;
     PyObject *retval = NULL;
 
-    if (o == NULL || name == NULL) {
+    if (obj == NULL || method == NULL) {
         return null_error();
     }
 
-    func = PyObject_GetAttrString(o, name);
-    if (func == NULL)
+    func = PyObject_GetAttrString(obj, method);
+    if (func == NULL) {
         return NULL;
+    }
 
     va_start(va, format);
     retval = callmethod(func, format, va, 0);
@@ -2611,20 +2612,20 @@ PyObject_CallMethod(PyObject *o, const char *name, const char *format, ...)
 }
 
 PyObject *
-_PyObject_CallMethodId(PyObject *o, _Py_Identifier *name,
+_PyObject_CallMethodId(PyObject *obj, _Py_Identifier *method,
                        const char *format, ...)
 {
     va_list va;
-    PyObject *func = NULL;
-    PyObject *retval = NULL;
+    PyObject *func, *retval;
 
-    if (o == NULL || name == NULL) {
+    if (obj == NULL || method == NULL) {
         return null_error();
     }
 
-    func = _PyObject_GetAttrId(o, name);
-    if (func == NULL)
+    func = _PyObject_GetAttrId(obj, method);
+    if (func == NULL) {
         return NULL;
+    }
 
     va_start(va, format);
     retval = callmethod(func, format, va, 0);
@@ -2634,20 +2635,21 @@ _PyObject_CallMethodId(PyObject *o, _Py_Identifier *name,
 }
 
 PyObject *
-_PyObject_CallMethod_SizeT(PyObject *o, const char *name,
+_PyObject_CallMethod_SizeT(PyObject *obj, const char *method,
                            const char *format, ...)
 {
     va_list va;
-    PyObject *func = NULL;
-    PyObject *retval;
+    PyObject *func, *retval;
 
-    if (o == NULL || name == NULL) {
+    if (obj == NULL || method == NULL) {
         return null_error();
     }
 
-    func = PyObject_GetAttrString(o, name);
-    if (func == NULL)
+    func = PyObject_GetAttrString(obj, method);
+    if (func == NULL) {
         return NULL;
+    }
+
     va_start(va, format);
     retval = callmethod(func, format, va, 1);
     va_end(va);
@@ -2656,21 +2658,21 @@ _PyObject_CallMethod_SizeT(PyObject *o, const char *name,
 }
 
 PyObject *
-_PyObject_CallMethodId_SizeT(PyObject *o, _Py_Identifier *name,
+_PyObject_CallMethodId_SizeT(PyObject *obj, _Py_Identifier *method,
                              const char *format, ...)
 {
     va_list va;
-    PyObject *func = NULL;
-    PyObject *retval;
+    PyObject *func, *retval;
 
-    if (o == NULL || name == NULL) {
+    if (obj == NULL || method == NULL) {
         return null_error();
     }
 
-    func = _PyObject_GetAttrId(o, name);
+    func = _PyObject_GetAttrId(obj, method);
     if (func == NULL) {
         return NULL;
     }
+
     va_start(va, format);
     retval = callmethod(func, format, va, 1);
     va_end(va);
@@ -2720,34 +2722,34 @@ objargs_mkstack(PyObject **small_stack, Py_ssize_t small_stack_size,
 }
 
 PyObject *
-PyObject_CallMethodObjArgs(PyObject *callable, PyObject *name, ...)
+PyObject_CallMethodObjArgs(PyObject *obj, PyObject *method, ...)
 {
     PyObject *small_stack[5];
     PyObject **stack;
     Py_ssize_t nargs;
-    PyObject *result;
+    PyObject *func, *result;
     va_list vargs;
 
-    if (callable == NULL || name == NULL) {
+    if (obj == NULL || method == NULL) {
         return null_error();
     }
 
-    callable = PyObject_GetAttr(callable, name);
-    if (callable == NULL)
+    func = PyObject_GetAttr(obj, method);
+    if (func == NULL)
         return NULL;
 
     /* count the args */
-    va_start(vargs, name);
+    va_start(vargs, method);
     stack = objargs_mkstack(small_stack, Py_ARRAY_LENGTH(small_stack),
                             vargs, &nargs);
     va_end(vargs);
     if (stack == NULL) {
-        Py_DECREF(callable);
+        Py_DECREF(func);
         return NULL;
     }
 
-    result = _PyObject_FastCall(callable, stack, nargs);
-    Py_DECREF(callable);
+    result = _PyObject_FastCall(func, stack, nargs);
+    Py_DECREF(func);
     if (stack != small_stack) {
         PyMem_Free(stack);
     }
@@ -2756,35 +2758,35 @@ PyObject_CallMethodObjArgs(PyObject *callable, PyObject *name, ...)
 }
 
 PyObject *
-_PyObject_CallMethodIdObjArgs(PyObject *callable,
-        struct _Py_Identifier *name, ...)
+_PyObject_CallMethodIdObjArgs(PyObject *obj,
+                              struct _Py_Identifier *method, ...)
 {
     PyObject *small_stack[5];
     PyObject **stack;
     Py_ssize_t nargs;
-    PyObject *result;
+    PyObject *func, *result;
     va_list vargs;
 
-    if (callable == NULL || name == NULL) {
+    if (obj == NULL || method == NULL) {
         return null_error();
     }
 
-    callable = _PyObject_GetAttrId(callable, name);
-    if (callable == NULL)
+    func = _PyObject_GetAttrId(obj, method);
+    if (func == NULL)
         return NULL;
 
     /* count the args */
-    va_start(vargs, name);
+    va_start(vargs, method);
     stack = objargs_mkstack(small_stack, Py_ARRAY_LENGTH(small_stack),
                             vargs, &nargs);
     va_end(vargs);
     if (stack == NULL) {
-        Py_DECREF(callable);
+        Py_DECREF(func);
         return NULL;
     }
 
-    result = _PyObject_FastCall(callable, stack, nargs);
-    Py_DECREF(callable);
+    result = _PyObject_FastCall(func, stack, nargs);
+    Py_DECREF(func);
     if (stack != small_stack) {
         PyMem_Free(stack);
     }
@@ -2793,7 +2795,7 @@ _PyObject_CallMethodIdObjArgs(PyObject *callable,
 }
 
 PyObject *
-PyObject_CallFunctionObjArgs(PyObject *callable, ...)
+PyObject_CallFunctionObjArgs(PyObject *func, ...)
 {
     PyObject *small_stack[5];
     PyObject **stack;
@@ -2801,12 +2803,12 @@ PyObject_CallFunctionObjArgs(PyObject *callable, ...)
     PyObject *result;
     va_list vargs;
 
-    if (callable == NULL) {
+    if (func == NULL) {
         return null_error();
     }
 
     /* count the args */
-    va_start(vargs, callable);
+    va_start(vargs, func);
     stack = objargs_mkstack(small_stack, Py_ARRAY_LENGTH(small_stack),
                             vargs, &nargs);
     va_end(vargs);
@@ -2814,7 +2816,7 @@ PyObject_CallFunctionObjArgs(PyObject *callable, ...)
         return NULL;
     }
 
-    result = _PyObject_FastCall(callable, stack, nargs);
+    result = _PyObject_FastCall(func, stack, nargs);
     if (stack != small_stack) {
         PyMem_Free(stack);
     }
diff --git a/Objects/typeobject.c b/Objects/typeobject.c
index 186c570..3cff904 100644
--- a/Objects/typeobject.c
+++ b/Objects/typeobject.c
@@ -1425,15 +1425,16 @@ _PyObject_LookupSpecial(PyObject *self, _Py_Identifier *attrid)
    as lookup_method to cache the interned name string object. */
 
 static PyObject *
-call_method(PyObject *o, _Py_Identifier *nameid, const char *format, ...)
+call_method(PyObject *obj, _Py_Identifier *method, const char *format, ...)
 {
     va_list va;
-    PyObject *func = NULL, *retval;
+    PyObject *func, *retval;
 
-    func = lookup_maybe(o, nameid);
+    func = lookup_maybe(obj, method);
     if (func == NULL) {
-        if (!PyErr_Occurred())
-            PyErr_SetObject(PyExc_AttributeError, nameid->object);
+        if (!PyErr_Occurred()) {
+            PyErr_SetObject(PyExc_AttributeError, method->object);
+        }
         return NULL;
     }
 
@@ -1465,12 +1466,12 @@ call_method(PyObject *o, _Py_Identifier *nameid, const char *format, ...)
 /* Clone of call_method() that returns NotImplemented when the lookup fails. */
 
 static PyObject *
-call_maybe(PyObject *o, _Py_Identifier *nameid, const char *format, ...)
+call_maybe(PyObject *obj, _Py_Identifier *method, const char *format, ...)
 {
     va_list va;
-    PyObject *func = NULL, *retval;
+    PyObject *func, *retval;
 
-    func = lookup_maybe(o, nameid);
+    func = lookup_maybe(obj, method);
     if (func == NULL) {
         if (!PyErr_Occurred())
             Py_RETURN_NOTIMPLEMENTED;