regression ST_LineCrossingDirection used to work with CIRCULARLINESTRING?

[robe]

POSTGIS="2.1.8 r13780" GEOS="3.5.0-CAPI-1.9.0 r4088" PROJ="Rel. 4.8.0, 6 March 2012" GDAL="GDAL 1.11.1, released 2014/09/24" LIBXML="2.7.8" LIBJSON="UNKNOWN" RASTER

POSTGIS="2.2.0dev r14092" GEOS="3.5.0-CAPI-1.9.0 r4088" PROJ="Rel. 4.9.1, 04 March 2015" GDAL="GDAL 2.0.1, released 2015/09/15" LIBXML="2.7.8" LIBJSON="0.12" RASTER

I'm not so concerned about this, cause I didn't know sT_LineCrossingDirection was ever supposed to work with curves, but evidentally in 2.1.8 it thought it did.

SELECT ST_LineCrossingDirection('LINESTRING(-11.1111111 70,70 -11.1111111)'::geometry,
    'CIRCULARSTRING(-71.0821 42.3036,-71.4821 42.3036,-71.7821 42.7036,-71.0821 42.7036,-71.0821 42.3036)'::geometry)

In 2.1.8, this returns 0

in 2.2.0 this returns:

ERROR:  This function only accepts LINESTRING as arguments.
CONTEXT:  SQL function "st_linecrossingdirection" statement 1

Fill free to dismiss as won't fix, if this was an intentional change.

[pramsey]

We're just being clearer about what we actually support, not regressing.