[postgis-devel] [PostGIS] #463: ST_AsSVG doesn't handle EMPTY inputs well

[PostGIS]

#463: ST_AsSVG doesn't handle EMPTY inputs well
---------------------+------------------------------------------------------
 Reporter:  pramsey  |       Owner:  colivier     
     Type:  defect   |      Status:  new          
 Priority:  medium   |   Milestone:  PostGIS 1.5.2
Component:  postgis  |     Version:  1.5.X        
 Keywords:           |  
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 As seen on the user list:
 {{{
 select assvg(difference(
 LineFromText('LINESTRING(535568 198842,535549 198802,535505 198820,535524
 198862,535568 198842)'),
 difference(LineFromText('LINESTRING(535568 198842,535549 198802,535505
 198820,535524 198862,535568 198842)'), LineFromText('LINESTRING(535900
 198600,535900 199100)'))
 ),0,5)

 Returns: empty row

 But

 select length(assvg(difference(
 LineFromText('LINESTRING(535568 198842,535549 198802,535505 198820,535524
 198862,535568 198842)'),
 difference(LineFromText('LINESTRING(535568 198842,535549 198802,535505
 198820,535524 198862,535568 198842)'), LineFromText('LINESTRING(535900
 198600,535900 199100)'))
 ),0,5))

 Returns: 5
 }}}
 Use lwgeom_is_empty() and return a null-terminated response pre-emptively.

-- 
Ticket URL: <http://trac.osgeo.org/postgis/ticket/463>
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