From 5b2a29f1f2c99b3277b314e6752b5bbcc31880f4 Mon Sep 17 00:00:00 2001
From: Sandro Santilli <strk@keybit.net>
Date: Tue, 3 Jan 2012 09:44:10 +0000
Subject: [PATCH] Don't consider shared nodes as edge intersections. Fixes
 #1428.

git-svn-id: http://svn.osgeo.org/postgis/trunk@8648 b70326c6-7e19-0410-871a-916f4a2858ee
---
 topology/sql/sqlmm.sql                        | 40 ++++++++++++++-----
 topology/test/regress/st_changeedgegeom.sql   |  4 ++
 .../test/regress/st_changeedgegeom_expected   |  3 +-
 3 files changed, 37 insertions(+), 10 deletions(-)

diff --git a/topology/sql/sqlmm.sql b/topology/sql/sqlmm.sql
index 6e6ec7dc9..fda288e24 100644
--- a/topology/sql/sqlmm.sql
+++ b/topology/sql/sqlmm.sql
@@ -2503,16 +2503,38 @@ BEGIN
   END LOOP;
 
   --
-  -- h) Check if curve intersects any other edge
-  -- 
-  FOR rec IN EXECUTE 'SELECT * FROM '
-    || quote_ident(atopology) || '.edge_data '
-    || ' WHERE edge_id != ' || anedge
-    || ' AND ST_Intersects(geom, '
-    || quote_literal(acurve::text) || '::geometry)'
+  -- h) Check if this geometry has any interaction with any existing edge
+  --
+  FOR rec IN EXECUTE 'SELECT edge_id, ST_Relate(geom,' 
+    || quote_literal(acurve::text)
+    || '::geometry, 2) as im FROM '
+    || quote_ident(atopology)
+    || '.edge_data WHERE geom && '
+    || quote_literal(acurve::text) || '::geometry'
   LOOP
-    RAISE EXCEPTION
-    'SQL/MM Spatial exception - geometry intersects an edge';
+
+    --RAISE DEBUG 'IM=%',rec.im;
+
+    IF ST_RelateMatch(rec.im, 'F********') THEN
+      CONTINUE; -- no interior-interior intersection
+    END IF;
+
+    IF ST_RelateMatch(rec.im, '1FFF*FFF2') THEN
+      RAISE EXCEPTION
+        'SQL/MM Spatial exception - coincident edge';
+    END IF;
+
+    -- NOT IN THE SPECS: geometry touches an edge
+    IF ST_RelateMatch(rec.im, '1********') THEN
+      RAISE EXCEPTION
+        'Spatial exception - geometry intersects edge %', rec.edge_id;
+    END IF;
+
+    IF ST_RelateMatch(rec.im, 'T********') THEN
+      RAISE EXCEPTION
+        'SQL/MM Spatial exception - geometry crosses an edge';
+    END IF;
+
   END LOOP;
 
   --
diff --git a/topology/test/regress/st_changeedgegeom.sql b/topology/test/regress/st_changeedgegeom.sql
index 72e2690dc..cc9a5ccfa 100644
--- a/topology/test/regress/st_changeedgegeom.sql
+++ b/topology/test/regress/st_changeedgegeom.sql
@@ -25,6 +25,10 @@ SELECT topology.ST_ChangeEdgeGeom('city_data', 666,
 SELECT topology.ST_ChangeEdgeGeom('city_data', 25,
  'LINESTRING(9 35, 11 40, 13 35)');
 
+-- Test change in presence of edges sharing node (#1428)
+SELECT topology.ST_ChangeEdgeGeom('city_data', 5,
+ 'LINESTRING(41 40, 57 33)');
+
 -- TODO: test changing closed edge
 -- TODO: test reverse direction of closed edge
 
diff --git a/topology/test/regress/st_changeedgegeom_expected b/topology/test/regress/st_changeedgegeom_expected
index 385828afc..4fcedf1a5 100644
--- a/topology/test/regress/st_changeedgegeom_expected
+++ b/topology/test/regress/st_changeedgegeom_expected
@@ -9,5 +9,6 @@ ERROR:  SQL/MM Spatial exception - start node not geometry start point.
 ERROR:  SQL/MM Spatial exception - end node not geometry end point.
 ERROR:  SQL/MM Spatial exception - geometry crosses a node
 ERROR:  SQL/MM Spatial exception - non-existent edge 666
-ERROR:  SQL/MM Spatial exception - geometry intersects an edge
+ERROR:  SQL/MM Spatial exception - geometry crosses an edge
+Edge 5 changed
 Topology 'city_data' dropped
-- 
2.49.0