Add tests for polygon ring methods

Author: yeesian

src/LibGEOS.jl

@@ -70,6 +70,7 @@ export Point,
     hasZ,
     isClosed,
     isValid,
+    interiorRing,
     interiorRings,
     exteriorRing,
     numGeometries,

src/geos_operations.jl

@@ -241,7 +241,7 @@ getGeometries(obj::Geometry, context::GEOSContext = _context) =
 # Converts Geometry to normal form (or canonical form).
 normalize!(obj::Geometry) = normalize!(obj.ptr)
 
-interiorRing(obj::Polygon, n::Integer) = interiorRing(obj.ptr, n)
+interiorRing(obj::Polygon, n::Integer) = LinearRing(interiorRing(obj.ptr, n))
 interiorRings(obj::Polygon) = map(LinearRing, interiorRings(obj.ptr))
 exteriorRing(obj::Polygon) = LinearRing(exteriorRing(obj.ptr))
 

test/test_geos_operations.jl

@@ -349,6 +349,19 @@ end
     # Geometry info
     # -----
 
+    @testset "Polygon ring(s)" begin
+        poly = readgeom(
+            "POLYGON ((35 10, 45 45, 15 40, 10 20, 35 10),(20 30, 35 35, 30 20, 20 30))",
+        )
+        @test LibGEOS.getCoordinates(LibGEOS.getCoordSeq(exteriorRing(poly).ptr)) ==
+            Vector{Float64}[[35, 10], [45, 45], [15, 40], [10, 20], [35, 10]]
+        @test length(interiorRings(poly)) == 1
+        @test LibGEOS.getCoordinates(LibGEOS.getCoordSeq(interiorRing(poly, 1).ptr)) ==
+            Vector{Float64}[[20, 30], [35, 35], [30, 20], [20, 30]]
+        @test_throws ErrorException interiorRing(poly, 0)
+        @test_throws ErrorException interiorRing(poly, 2)
+    end
+
     @testset "numGeometries" begin
         @test numGeometries(readgeom("POINT(2 2)")) == 1
         @test numGeometries(readgeom("MULTIPOINT(0 0, 5 0, 10 0)")) == 3