Remove workaround for new datum types (#693)

Author: snowman2

pyproj/_crs.pyx

@@ -1317,14 +1317,14 @@ cdef class PrimeMeridian(_CRSParts):
 
 
 _DATUM_TYPE_MAP = {
-    "GeodeticReferenceFrame": "Geodetic Reference Frame",
-    "DynamicGeodeticReferenceFrame": "Dynamic Geodetic Reference Frame",
-    "VerticalReferenceFrame": "Vertical Reference Frame",
-    "DynamicVerticalReferenceFrame": "Dynamic Vertical Reference Frame",
-    "DatumEnsemble": "Datum Ensemble",
-    "TemporalDatum": "Temporal Datum",
-    "EngineeringDatum": "Engineering Datum",
-    "ParametricDatum": "Parametric Datum",
+    PJ_TYPE_GEODETIC_REFERENCE_FRAME: "Geodetic Reference Frame",
+    PJ_TYPE_DYNAMIC_GEODETIC_REFERENCE_FRAME: "Dynamic Geodetic Reference Frame",
+    PJ_TYPE_VERTICAL_REFERENCE_FRAME: "Vertical Reference Frame",
+    PJ_TYPE_DYNAMIC_VERTICAL_REFERENCE_FRAME: "Dynamic Vertical Reference Frame",
+    PJ_TYPE_DATUM_ENSEMBLE: "Datum Ensemble",
+    PJ_TYPE_TEMPORAL_DATUM: "Temporal Datum",
+    PJ_TYPE_ENGINEERING_DATUM: "Engineering Datum",
+    PJ_TYPE_PARAMETRIC_DATUM: "Parametric Datum",
 }
 
 _PJ_DATUM_TYPE_MAP = {
@@ -1338,19 +1338,6 @@ _PJ_DATUM_TYPE_MAP = {
 }
 
 
-cdef _get_datum_type_name(PJ_CONTEXT* context, PJ* datum):
-    # workaround: https://github.com/OSGeo/PROJ/pull/2274
-    cdef const char* proj_json_string = proj_as_projjson(
-        context,
-        datum,
-        NULL,
-    )
-    if proj_json_string == NULL:
-        return None
-    json_dict = json.loads(cstrdecode(proj_json_string))
-    return _DATUM_TYPE_MAP.get(json_dict["type"])
-
-
 cdef class Datum(_CRSParts):
     """
     .. versionadded:: 2.2.0
@@ -1378,7 +1365,7 @@ cdef class Datum(_CRSParts):
         datum.context = context
         datum.projobj = datum_pj
         datum._set_base_info()
-        datum.type_name = _get_datum_type_name(datum.context, datum.projobj)
+        datum.type_name = _DATUM_TYPE_MAP[proj_get_type(datum.projobj)]
         return datum
 
     @staticmethod
@@ -1458,7 +1445,7 @@ cdef class Datum(_CRSParts):
         )
         if (
             datum_pj == NULL or
-            _get_datum_type_name(context, datum_pj) is None
+             proj_get_type(datum_pj) not in _DATUM_TYPE_MAP
         ):
             proj_destroy(datum_pj)
             proj_context_destroy(context)

pyproj/proj.pxi

@@ -187,6 +187,9 @@ cdef extern from "proj.h":
         PJ_TYPE_TRANSFORMATION
         PJ_TYPE_CONCATENATED_OPERATION
         PJ_TYPE_OTHER_COORDINATE_OPERATION
+        PJ_TYPE_TEMPORAL_DATUM
+        PJ_TYPE_ENGINEERING_DATUM
+        PJ_TYPE_PARAMETRIC_DATUM
 
     PJ_TYPE proj_get_type(const PJ *obj)
     const char* proj_get_name(const PJ *obj)