Re: next-single-property-change

[Chong Yidong]

Richard Stallman <address@hidden> writes:

> Would someone please install this change and ack?

Done.  (I updated FOR-RELEASE too).

> From: Stefan Monnier <address@hidden>
> Date: Fri, 08 Sep 2006 17:29:32 -0400
>
>> Would someone please fix this and DTRT?
>
>> The docsting of next-single-property-change promises that it will
>> never return a value equal to the position given, but it does if the
>> buffer is narrowed and the next property change occurs after the
>> narrowed region.  Test case:
>
> I believe the patch below corrects this problem (for related functions as
> well).  Can you confirm?
>
>
>         Stefan
>
>
> --- orig/src/textprop.c
> +++ mod/src/textprop.c
> @@ -1001,17 +1001,16 @@
>        && (NILP (limit) || next->position < XFASTINT (limit)))
>      next = next_interval (next);
>  
> -  if (NULL_INTERVAL_P (next))
> -    return limit;
> -  if (NILP (limit))
> -    XSETFASTINT (limit, (STRINGP (object)
> -                      ? SCHARS (object)
> -                      : BUF_ZV (XBUFFER (object))));
> -  if (!(next->position < XFASTINT (limit)))
> +  if (NULL_INTERVAL_P (next)
> +      || (next->position
> +       >= (INTEGERP (limit)
> +           ? XFASTINT (limit)
> +           : (STRINGP (object)
> +              ? SCHARS (object)
> +              : BUF_ZV (XBUFFER (object))))))
>      return limit;
> -
> -  XSETFASTINT (position, next->position);
> -  return position;
> +  else
> +    return make_number (next->position);
>  }
>  
>  /* Return 1 if there's a change in some property between BEG and END.  */
> @@ -1083,16 +1082,16 @@
>        && (NILP (limit) || next->position < XFASTINT (limit)))
>      next = next_interval (next);
>  
> -  if (NULL_INTERVAL_P (next))
> -    return limit;
> -  if (NILP (limit))
> -    XSETFASTINT (limit, (STRINGP (object)
> -                      ? SCHARS (object)
> -                      : BUF_ZV (XBUFFER (object))));
> -  if (!(next->position < XFASTINT (limit)))
> +  if (NULL_INTERVAL_P (next)
> +      || (next->position
> +       >= (INTEGERP (limit)
> +           ? XFASTINT (limit)
> +           : (STRINGP (object)
> +              ? SCHARS (object)
> +              : BUF_ZV (XBUFFER (object))))))
>      return limit;
> -
> -  return make_number (next->position);
> +  else
> +    return make_number (next->position);
>  }
>  
>  DEFUN ("previous-property-change", Fprevious_property_change,
> @@ -1132,14 +1131,15 @@
>        && (NILP (limit)
>            || (previous->position + LENGTH (previous) > XFASTINT (limit))))
>      previous = previous_interval (previous);
> -  if (NULL_INTERVAL_P (previous))
> -    return limit;
> -  if (NILP (limit))
> -    XSETFASTINT (limit, (STRINGP (object) ? 0 : BUF_BEGV (XBUFFER 
> (object))));
> -  if (!(previous->position + LENGTH (previous) > XFASTINT (limit)))
> -    return limit;
>  
> -  return make_number (previous->position + LENGTH (previous));
> +  if (NULL_INTERVAL_P (previous)
> +      || (previous->position + LENGTH (previous)
> +       <= (INTEGERP (limit)
> +           ? XFASTINT (limit)
> +           : (STRINGP (object) ? 0 : BUF_BEGV (XBUFFER (object))))))
> +    return limit;
> +  else
> +    return make_number (previous->position + LENGTH (previous));
>  }
>  
>  DEFUN ("previous-single-property-change", Fprevious_single_property_change,
> @@ -1184,14 +1184,15 @@
>        && (NILP (limit)
>            || (previous->position + LENGTH (previous) > XFASTINT (limit))))
>      previous = previous_interval (previous);
> -  if (NULL_INTERVAL_P (previous))
> -    return limit;
> -  if (NILP (limit))
> -    XSETFASTINT (limit, (STRINGP (object) ? 0 : BUF_BEGV (XBUFFER 
> (object))));
> -  if (!(previous->position + LENGTH (previous) > XFASTINT (limit)))
> -    return limit;
>  
> -  return make_number (previous->position + LENGTH (previous));
> +  if (NULL_INTERVAL_P (previous)
> +      || (previous->position + LENGTH (previous)
> +       <= (INTEGERP (limit)
> +           ? XFASTINT (limit)
> +           : (STRINGP (object) ? 0 : BUF_BEGV (XBUFFER (object))))))
> +    return limit;
> +  else
> +    return make_number (previous->position + LENGTH (previous));
>  }
>  
>  /* Callers note, this can GC when OBJECT is a buffer (or nil).  */