How to add a regression test
----------------------------

1. Write a /regress/<testname>.sql file with data and sql queries for testing
2. Write a /regress/<testname>_expected or <testname>_expected.in file with 
   expected results per query
   The expected results provided in the <testname>_expected file must be 
   formatted using the following psql options:
      -a -- unaligned columns
      -f | -- use | (pipe) as the field separator between columns
      -t -- output rows only, ie. no table header

   cat file.sql | psql -F\| -t -A > file_expected

3. Edit regress/Makefile adding <testname> to the TESTS variable.
   Any _expected.in files need to be added to the PREPROC variable.

Notes about changes in regression tests introduces with PostGIS 1.1.0
---------------------------------------------------------------------

- Mixed-dimensioned geometries are no longer supported
  (previous behaviour was to fill Z with a 0 value)
  [ updated to use new behaviour ]

- geometry_same operator (=~) now requires all dimensions equality
  Previously only x/y were checked

- geometry_same operator (=~) now requires geom type equality
  Previous behaviour:
     GEOMETRYCOLLECTION(POINT(0 1), POINT(2 3)) =~  MULTIPOINT(0 1,2 3)

- numb_sub_geometries does not exist anymore
  [updated to use numgeometries]

- truly_inside does not exist anymore
  [updated to use within]

Notes about <testname>_expected.in
----------------------------------

The first line of the <testname>_expected.in should include the postgis
configuration header.

  #include "../postgis_config.h"

The ability to run a c preprocessor over the expected results prior to 
regression testing was needed for testing curved string functionality that
would elicit different responses from JTS vs GEOS compilations.  Since
JTS is no longer supported, this may not be required anymore.


