add chainrules testing packages

Author: mileslucas

test/Project.toml

@@ -1,9 +1,12 @@
 [deps]
+ChainRulesCore = "d360d2e6-b24c-11e9-a2a3-2a2ae2dbcce4"
 ChainRulesTestUtils = "cdddcdb0-9152-4a09-a978-84456f9df70a"
 RecipesBase = "3cdcf5f2-1ef4-517c-9805-6587b60abb01"
 StaticArrays = "90137ffa-7385-5640-81b9-e52037218182"
 Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 
 [compat]
+ChainRulesCore = "1"
+ChainRulesTestUtils = "1"
 RecipesBase = "1"
 StaticArrays = "0.12, 1"

test/runtests.jl

@@ -1,3 +1,5 @@
+using ChainRulesCore
+using ChainRulesTestUtils
 using PSFModels
 using PSFModels: Gaussian, Normal, AiryDisk, Moffat
 using StaticArrays
@@ -68,6 +70,10 @@ function test_model_interface(K)
     @test m(m.pos) ≈ BigFloat(1)
 end
 
+function test_model_grads(K)
+
+end
+
 @testset "Model Interface - $K" for K in (Gaussian, AiryDisk, Moffat)
     test_model_interface(K)
 end