From: Sandro Santilli <strk@keybit.net>
Date: Wed, 14 Dec 2011 14:37:18 +0000 (+0000)
Subject: Return empty geoms snapped to a grid as immutated (#1089)
X-Git-Tag: 2.0.0alpha1~465
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=ed841457ad164462307718a9ece55c898cf4d92b;p=postgis

Return empty geoms snapped to a grid as immutated (#1089)

Also introduces an "empty" regression test

git-svn-id: http://svn.osgeo.org/postgis/trunk@8408 b70326c6-7e19-0410-871a-916f4a2858ee
---

diff --git a/postgis/lwgeom_functions_analytic.c b/postgis/lwgeom_functions_analytic.c
index 4354a7195..45682795b 100644
--- a/postgis/lwgeom_functions_analytic.c
+++ b/postgis/lwgeom_functions_analytic.c
@@ -530,8 +530,8 @@ Datum LWGEOM_snaptogrid(PG_FUNCTION_ARGS)
 	/* Do not support gridding Z and M values for now */
 	grid.ipz=grid.ipm=grid.zsize=grid.msize=0;
 
-	/* Return input geometry if grid is null */
-	if ( grid_isNull(&grid) )
+	/* Return input geometry if grid is null or input geometry is empty */
+	if ( grid_isNull(&grid) || gserialized_is_empty(in_geom) )
 	{
 		PG_RETURN_POINTER(in_geom);
 	}
diff --git a/regress/Makefile.in b/regress/Makefile.in
index 67e82b993..d0625da90 100644
--- a/regress/Makefile.in
+++ b/regress/Makefile.in
@@ -58,6 +58,7 @@ TESTS = \
 	snaptogrid \
 	summary \
 	affine \
+	empty \
 	measures \
 	long_xact \
 	ctors \
diff --git a/regress/empty.sql b/regress/empty.sql
new file mode 100644
index 000000000..d4e40ea70
--- /dev/null
+++ b/regress/empty.sql
@@ -0,0 +1,3 @@
+SELECT 'T1.1', ST_AsEWKT(ST_SnapToGrid('POINT EMPTY', 1));
+SELECT 'T1.2', ST_AsEWKT(ST_SnapToGrid('LINESTRING EMPTY', 1));
+SELECT 'T1.3', ST_AsEWKT(ST_SnapToGrid('SRID=4326;POLYGON EMPTY', 1));
diff --git a/regress/empty_expected b/regress/empty_expected
new file mode 100644
index 000000000..7bca4a358
--- /dev/null
+++ b/regress/empty_expected
@@ -0,0 +1,3 @@
+T1.1|POINT EMPTY
+T1.2|LINESTRING EMPTY
+T1.3|SRID=4326;POLYGON EMPTY