B03008 - stop_occupation while digging in a pit

If you dug in a pit next to a sleeping, angry monster, you'd stop every
turn due to a complex check at the end of dochugw.  It turned out this
was due to a long-standing bug in the special case vision code that failed
to set the COULD_SEE bit for the locations where it set the IN_SIGHT bit.
It looks like the underwater code had the same problem (it didn't set the
bit, obviously there are no pits underwater).  However, the same could
occur if you see the angry, sleeping monster with Xray vision.  In this
case, setting COULD_SEE is not appropriate, so added a mcanmove check to
the complex check in dochugw.

doc/fixes34.2

@@ -103,6 +103,7 @@ revived pet corpse from bones file should not be loyal to current player
 finding a statue trap you are about to dig should stop your occupation
 try to keep saddle at the same location as the steed corpse
 never display I symbol on the mounted hero/steed location
+pit digging is no longer stopped by a sleeping monster next to you
 
 
 Platform- and/or Interface-Specific Fixes

src/monmove.c

@@ -116,6 +116,7 @@ dochugw(mtmp)
 	    /* can see it now, or sense it and would normally see it */
 	    (canseemon(mtmp) ||
 		(sensemon(mtmp) && couldsee(mtmp->mx,mtmp->my))) &&
+	    mtmp->mcanmove &&
 	    !noattacks(mtmp->data) && !onscary(u.ux, u.uy, mtmp))
 		stop_occupation();
 

src/vision.c

@@ -587,7 +587,7 @@ vision_recalc(control)
 
 		    next_rmin[row] = min(next_rmin[row], col);
 		    next_rmax[row] = max(next_rmax[row], col);
-		    next_array[row][col] = IN_SIGHT;
+		    next_array[row][col] = IN_SIGHT | COULD_SEE;
 		}
 	}
 
@@ -601,7 +601,7 @@ vision_recalc(control)
 		next_row = next_array[row];
 
 		for(col=next_rmin[row]; col <= next_rmax[row]; col++)
-		    next_row[col] = IN_SIGHT;
+		    next_row[col] = IN_SIGHT | COULD_SEE;
 	    }
 	} else
 	    view_from(u.uy, u.ux, next_array, next_rmin, next_rmax,