Bug #1043845 st_distance() results are incorrect depending on variable order.

        Autointersections of an object were treated as nodes, so the wrong result.

per-file comments:
  mysql-test/r/gis.result
Bug #1043845 st_distance() results are incorrect depending on variable order.
        test result updated.
  mysql-test/t/gis.test
Bug #1043845 st_distance() results are incorrect depending on variable order.
        test case added.
  sql/item.cc
        small fix to make compilers happy.
  sql/item_geofunc.cc
Bug #1043845 st_distance() results are incorrect depending on variable order.
        Skip intersection points when calculate distance.

mysql-test/r/gis.result

@@ -1473,3 +1473,26 @@ WHERE ST_Contains(ST_Buffer(bridges.position, 15.0), buildings.footprint) = 1;
 count(*)
 1
 DROP DATABASE gis_ogs;
+#
+# BUG #1043845 st_distance() results are incorrect depending on variable order
+#
+select st_distance(geomfromtext('LINESTRING(-95.9673005697771 36.13509598461,
+                                            -95.9673057475387 36.1344478941074,
+                                            -95.9673063519371 36.134484524621,
+                                            -95.9673049102515 36.1343976584193)'),
+geomfromtext('point(-95.96269500000000000000 36.14181833333330000000)')) ;
+st_distance(geomfromtext('LINESTRING(-95.9673005697771 36.13509598461,
+                                            -95.9673057475387 36.1344478941074,
+                                            -95.9673063519371 36.134484524621,
+                         
+0.008148695928138
+select st_distance(geomfromtext('point(-95.96269500000000000000 36.14181833333330000000)'),
+geomfromtext('LINESTRING(-95.9673005697771 36.13509598461,
+                           -95.9673057475387 36.1344478941074,
+                           -95.9673063519371 36.134484524621,
+                           -95.9673049102515 36.1343976584193) ')) ;
+st_distance(geomfromtext('point(-95.96269500000000000000 36.14181833333330000000)'),
+geomfromtext('LINESTRING(-95.9673005697771 36.13509598461,
+                           -95.9673057475387 36.1344478941074,
+                           -95.9673063519371 36.
+0.008148695928138

mysql-test/t/gis.test

@@ -1355,3 +1355,19 @@ WHERE ST_Contains(ST_Buffer(bridges.position, 15.0), buildings.footprint) = 1;
 #WHERE lakes.name = 'Blue Lake'; 
 
 DROP DATABASE gis_ogs;
+
+--echo #
+--echo # BUG #1043845 st_distance() results are incorrect depending on variable order
+--echo #
+
+select st_distance(geomfromtext('LINESTRING(-95.9673005697771 36.13509598461,
+                                            -95.9673057475387 36.1344478941074,
+                                            -95.9673063519371 36.134484524621,
+                                            -95.9673049102515 36.1343976584193)'),
+  geomfromtext('point(-95.96269500000000000000 36.14181833333330000000)')) ;
+select st_distance(geomfromtext('point(-95.96269500000000000000 36.14181833333330000000)'),
+  geomfromtext('LINESTRING(-95.9673005697771 36.13509598461,
+                           -95.9673057475387 36.1344478941074,
+                           -95.9673063519371 36.134484524621,
+                           -95.9673049102515 36.1343976584193) ')) ;
+

sql/item.cc

@@ -8858,7 +8858,7 @@ bool Item_type_holder::join_types(THD *thd, Item *item)
                        item->max_length, item->decimals));
   fld_type= Field::field_type_merge(fld_type, get_real_type(item));
   {
-    int item_decimals= item->decimals;
+    uint item_decimals= item->decimals;
     /* fix variable decimals which always is NOT_FIXED_DEC */
     if (Field::result_merge_type(fld_type) == INT_RESULT)
       item_decimals= 0;

sql/item_geofunc.cc

@@ -1693,7 +1693,8 @@ double Item_func_distance::val_real()
     for (dist_point= collector.get_first(); dist_point; dist_point= dist_point->get_next())
     {
       /* We only check vertices of object 2 */
-      if (dist_point->shape < obj2_si)
+      if (dist_point->type != Gcalc_heap::nt_shape_node ||
+          dist_point->shape < obj2_si)
         continue;
 
       /* if we have an edge to check */