Correctly implement interface for wrapper geometry. (#169)

* Correctly implement interface for wrapper geometry.

* Test for correct implementations.

* Direct call of two/three argument methods.

src/utils.jl

@@ -8,15 +8,21 @@ function testgeometry(geom)
     type = geomtrait(geom)
     @assert !isnothing(type) "$geom doesn't implement `geomtrait`."
 
+    @assert hasmethod(ncoord, (typeof(type), typeof(geom))) "$geom does not correctly implement two argument `ncoord`"
+
     if type == PointTrait()
         n = ncoord(geom)
+        @assert n == ncoord(type, geom) "$geom does not correctly implement three argument `getcoord`"
         if n >= 1  # point could be empty
-            getcoord(geom, 1)  # point always needs at least 2
+            c = getcoord(geom, 1)  # point always needs at least 2
+            @assert c == getcoord(type, geom, 1) "$geom does not correctly implement three argument `getcoord`"
         end
     else
         n = ngeom(geom)
+        @assert n == ngeom(type, geom) "$geom does not correctly implement two argument `ngeom`"
         if n >= 1  # geometry could be empty
             g2 = getgeom(geom, 1)
+            @assert g2 == getgeom(type, geom, 1) "$geom does not correctly implement three argument `getgeom`"
             subtype = subtrait(type)
             if !isnothing(subtype)
                 issub = geomtrait(g2) isa subtype

src/wrappers.jl

@@ -61,9 +61,9 @@ measures.
 abstract type WrapperGeometry{Z,M,T,C} end
 
 isgeometry(::Type{<:WrapperGeometry}) = true
-is3d(::WrapperGeometry{Z}) where Z = Z
-ismeasured(::WrapperGeometry{<:Any,M})  where M = M
-ncoord(::WrapperGeometry{Z, M}) where {Z, M} = 2 + Z + M
+is3d(::AbstractGeometryTrait, ::WrapperGeometry{Z}) where Z = Z
+ismeasured(::AbstractGeometryTrait, ::WrapperGeometry{<:Any,M})  where M = M
+ncoord(::AbstractGeometryTrait, ::WrapperGeometry{Z, M}) where {Z, M} = 2 + Z + M
 
 Base.parent(geom::WrapperGeometry) = geom.geom