convert to module types

Author: rafaqz

src/fallbacks.jl

@@ -109,6 +109,15 @@ function coordinates(t::AbstractFeatureTrait, feature)
 end
 coordinates(t::AbstractFeatureCollectionTrait, fc) = [coordinates(f) for f in getfeature(fc)]
 
+# Package level `GeoInterface.convert` method
+# Packages must implement their own `traittype` method
+# that accepts a GeoInterface.jl trait and returns the
+# corresponding geometry type
+function convert(package::Module, geom)
+    t = trait(geom)
+    convert(package.geointerface_traittype(t), t, geom)
+end
+
 # Subtraits
 
 """

src/interface.jl

@@ -605,8 +605,12 @@ coordinates(obj) = coordinates(trait(obj), obj)
 
 """
     convert(type::CustomGeom, geom)
+    convert(module::Module, geom)
 
 Create a `CustomGeom` from any `geom` that implements the GeoInterface.
+
+Can also convert to a `Module`, which finds the corresponding
+geom type for the trait using the modules `geointerface_traittype` method.
 """
 convert(T, geom) = convert(T, geomtrait(geom), geom)
 convert(::Type{T}, x::T) where {T} = x  # no-op

test/test_primitives.jl

@@ -366,4 +366,19 @@ end
         @test GeoInterface.testfeature(feature)
         @test GeoInterface.testfeaturecollection([feature, feature])
     end
+
+    module ConvertTestModule
+        using GeoInterface
+        struct TestPolygon end
+        geointerface_traittype(::GeoInterface.PolygonTrait) = TestPolygon
+
+        GeoInterface.isgeometry(::TestPolygon) = true
+        GeoInterface.geomtrait(::TestPolygon) = PolygonTrait()
+        GeoInterface.ngeom(::PolygonTrait, geom::TestPolygon) = 2
+        GeoInterface.getgeom(::PolygonTrait, geom::TestPolygon, i) = TestCurve()
+        GeoInterface.convert(::Type{<:TestPolygon}, ::PolygonTrait, geom) = TestPolygon()
+    end
+
+    @test GeoInterface.convert(ConvertTestModule, MyPolygon()) == ConvertTestModule.TestPolygon()
+
 end