clean up self assign slice operation

Author: philippedistributive

src/JSArrayProxy.cc

@@ -175,21 +175,14 @@ static int list_ass_slice(JSArrayProxy *self, Py_ssize_t ilow, Py_ssize_t ihigh,
   size_t s;
   int result = -1;              /* guilty until proved innocent */
 #define b ((PyListObject *)v)
+  Py_ssize_t selfLength = JSArrayProxyMethodDefinitions::JSArrayProxy_length(self);
   if (v == NULL) {
     n = 0;
   }
   else {
-    Py_ssize_t vLength;
-    if (PyObject_TypeCheck(v, &JSArrayProxyType)) {
-      vLength = JSArrayProxyMethodDefinitions::JSArrayProxy_length((JSArrayProxy *)v);
-    }
-    else {
-      vLength = Py_SIZE(b);
-    }
-
     if ((PyListObject *)self == b) {
       /* Special case "a[i:j] = a" -- copy b first */
-      v = list_slice(self, 0, vLength);
+      v = list_slice(self, 0, selfLength);
       if (v == NULL) {
         return result;
       }
@@ -206,8 +199,6 @@ static int list_ass_slice(JSArrayProxy *self, Py_ssize_t ilow, Py_ssize_t ihigh,
     vitem = PySequence_Fast_ITEMS(v_as_SF);
   }
 
-  Py_ssize_t selfLength = JSArrayProxyMethodDefinitions::JSArrayProxy_length(self);
-
   if (ilow < 0) {
     ilow = 0;
   }