Use SWIG's %argument_fail macro more widely

Author: jim-easterbrook

src/gphoto2/context.i

@@ -222,7 +222,7 @@ CB_WRAPPER(void, py_progress_stop, (GPContext *context, unsigned int id, void *d
 }
 %typemap(in) cb_func_type {
     if (!PyCallable_Check($input)) {
-        SWIG_exception_fail(SWIG_TypeError, "in method '" "$symname" "', argument " "$argnum" " is not callable");
+        %argument_fail(SWIG_TypeError, callable, $symname, $argnum);
     }
     _global_callbacks->func_1 = $input;
     Py_INCREF(_global_callbacks->func_1);
@@ -259,7 +259,7 @@ SINGLE_CALLBACK_FUNCTION(GPContextProgressStartFunc,
 // Use typemaps for other two functions
 %typemap(in) GPContextProgressUpdateFunc {
     if (!PyCallable_Check($input)) {
-        SWIG_exception_fail(SWIG_TypeError, "in method '" "$symname" "', argument " "$argnum" " is not callable");
+        %argument_fail(SWIG_TypeError, callable, $symname, $argnum);
     }
     _global_callbacks->func_2 = $input;
     Py_INCREF(_global_callbacks->func_2);
@@ -269,7 +269,7 @@ SINGLE_CALLBACK_FUNCTION(GPContextProgressStartFunc,
 
 %typemap(in) GPContextProgressStopFunc {
     if (!PyCallable_Check($input)) {
-        SWIG_exception_fail(SWIG_TypeError, "in method '" "$symname" "', argument " "$argnum" " is not callable");
+        %argument_fail(SWIG_TypeError, callable, $symname, $argnum);
     }
     _global_callbacks->func_3 = $input;
     Py_INCREF(_global_callbacks->func_3);

src/gphoto2/port_log.i

@@ -121,7 +121,7 @@ static void gp_log_call_python(GPLogLevel level, const char *domain,
 }
 %typemap(in) GPLogFunc {
     if (!PyCallable_Check($input)) {
-        SWIG_exception_fail(SWIG_TypeError, "in method '" "$symname" "', argument " "$argnum" " is not callable");
+        %argument_fail(SWIG_TypeError, callable, $symname, $argnum);
     }
     _global_callback->func = $input;
     Py_INCREF(_global_callback->func);

src/gphoto2/widget.i

@@ -145,14 +145,14 @@ int gp_widget_get_value(CameraWidget *widget, void *value_out);
     case GP_WIDGET_TOGGLE:
       res = SWIG_AsVal_int($input, &value.int_val);
       if (!SWIG_IsOK(res)) {
-        %argument_fail(res, int, $symname, 2);
+        %argument_fail(res, int, $symname, $argnum);
       }
       $1 = &value.int_val;
       break;
     case GP_WIDGET_RANGE:
       res = SWIG_AsVal_float($input, &value.flt_val);
       if (!SWIG_IsOK(res)) {
-        %argument_fail(res, float, $symname, 2);
+        %argument_fail(res, float, $symname, $argnum);
       }
       $1 = &value.flt_val;
       break;
@@ -161,7 +161,7 @@ int gp_widget_get_value(CameraWidget *widget, void *value_out);
     case GP_WIDGET_RADIO:
       res = SWIG_AsCharPtrAndSize($input, &value.str_val, NULL, &alloc);
       if (!SWIG_IsOK(res)) {
-        %argument_fail(res, str, $symname, 2);
+        %argument_fail(res, str, $symname, $argnum);
       }
       // Note this is a pointer set by SWIG_AsCharPtrAndSize, not the address of value
       $1 = value.str_val;