Test that error message is correctly thrown

Author: penelopeysm

test/logdensityproblems.jl

@@ -22,6 +22,13 @@
         @test model.logdensity === ℓ
 
         @test_throws ArgumentError AbstractMCMC.LogDensityModel(mylogdensity)
+
+        try
+            LogDensityProblems.logdensity(model, ones(10))
+        catch exc
+            @test exc isa MethodError
+            @test occursin("is a wrapper", sprint(showerror, exc))
+        end
     end
 
     @testset "fallback for log densities" begin