tests for dictionaries (#1330)

* tests for issue 717

* test for issue 760

* fix tests

* add .vscode to gitignore

* cleanup

.gitignore

@@ -5,3 +5,4 @@ docs/build
 docs/Manifest.toml
 Manifest.toml
 dev/
+.vscode/

test/features.jl

@@ -817,3 +817,21 @@ end
   @test gradient(xs -> sum(map(x->x.im^2, xs)), [1+2im,3])[1] == [4im, 0]
   @test gradient(xs -> mapreduce(x->x.im^2, +, xs), [1+2im,3])[1] == [4im, 0]
 end
+
+@testset "Dict" begin
+  # issue #717
+  @test gradient(x -> (() -> x[:y])(), Dict(:y => 0.4)) == (Dict(:y => 1.0),)
+
+  ntd = (; data = Dict("x" => rand(2)))
+  @test gradient(x -> sum(x.data["x"]), ntd)[1] == (; data = Dict("x" => ones(2)))
+
+  # issue #760
+  function f760(x)
+    d = Dict()
+    for i in 1:4
+        push!(d, i=>i^x)
+    end
+    sum(values(d))
+  end
+  @test gradient(f760, 3)[1] ≈ 123.93054835019153
+end