ST_Collect is screwy with M dimension

[robe]

SELECT ST_AsEWKT(ST_Collect(ST_GeomFromEWKT('SRID=4326;POLYGONM((-71.1261 42.2703 1,-71.1257 42.2703 1,-71.1257 42.2701 2,-71.126 42.2701 1,-71.1261 42.2702 1,-71.1261 42.2703 1))'),

	ST_GeomFromEWKT('SRID=4326;MULTIPOLYGONM(((-71.0821 42.3036 2,-71.0822 42.3036 3,-71.082 42.3038 2,-71.0819 42.3037 2,-71.0821 42.3036 2)))') ));

Yields:

SRID=4326;GEOMETRYCOLLECTIONM(POLYGON((-71.1261 42.2703 1,-71.1257 42.2703 1,-71.1257 42.2701 2,-71.126 42.2701 1,-71.1261 42.2702 1,-71.1261 42.2703 1)),MULTIPOLYGON(((-71.0821 42.3036 2,-71.0822 42.3036 3,-71.082 42.3038 2,-71.0819 42.3037 2,-71.0821 42.3036 2))))

Which causes this

SELECT ST_GeogFromText(ST_AsEWKT(ST_Collect(ST_GeomFromEWKT('SRID=4326;POLYGONM((-71.1261 42.2703 1,-71.1257 42.2703 1,-71.1257 42.2701 2,-71.126 42.2701 1,-71.1261 42.2702 1,-71.1261 42.2703 1))'),

	ST_GeomFromEWKT('SRID=4326;MULTIPOLYGONM(((-71.0821 42.3036 2,-71.0822 42.3036 3,-71.082 42.3038 2,-71.0819 42.3037 2,-71.0821 42.3036 2)))') )));

To fail with error:

ERROR:  can not mix dimensionality in a geometry
HINT:  "...0819 42.3037 2,-71.0821 42.3036 2))))" <-- parse error at position 266 within geometry

It's the same issue in 1.5, but 1.5 doesn't error out with ST_Geog because evidentally 1.5 c\geog check doesn't care as much about dimensionality as 2.0 does.

[pramsey]

This is a WKT parser "problem". I guess in the spirit of backwards compatibility it needs to be resolved. As the parser works up from the inside, it's not clear that the 3d coordinate sets are XYM and now XYZ until it gets to the final type tag at the top. I've fought with this issue a number of times. Back into the guts.

[strk]

This should be fixed with r8741