Test more parts of Optim interface

Author: MilesCranmer

ext/DynamicExpressionsOptimExt.jl

@@ -27,9 +27,6 @@ end
 function Base.propertynames(r::ExpressionOptimizationResults)
     return (:tree, propertynames(getfield(r, :_results))...)
 end
-function base_results(r::ExpressionOptimizationResults)
-    return getfield(r, :_results)
-end
 function Optim.minimizer(r::ExpressionOptimizationResults)
     return r.tree
 end

test/test_optim.jl

@@ -45,7 +45,10 @@ end
 
     res = optimize(f, g!, tree, BFGS())
     @test did_i_run[]
+    @test res.f_calls > 0
     @test isapprox(get_constants(res.minimizer), get_constants(target_tree); atol=0.01)
+    @test Optim.minimizer(res) === res.minimizer
+    @test propertynames(res) == (:tree, propertynames(getfield(res, :_results))...)
 
     @testset "Hessians not implemented" begin
         @test_throws ArgumentError optimize(f, g!, t -> t, tree, BFGS())