Pass keyword arguments to test_approx when checking thunks (#247)

* Pass keyword arguments to `test_approx` when checking chunks

* Update Project.toml

* Fix tests

Author: devmotion

Project.toml

@@ -1,6 +1,6 @@
 name = "ChainRulesTestUtils"
 uuid = "cdddcdb0-9152-4a09-a978-84456f9df70a"
-version = "1.7.0"
+version = "1.7.1"
 
 [deps]
 ChainRulesCore = "d360d2e6-b24c-11e9-a2a3-2a2ae2dbcce4"

src/testers.jl

@@ -227,7 +227,7 @@ function test_rrule(
         end
 
         if check_thunked_output_tangent
-            test_approx(ad_cotangents, pullback(@thunk(ȳ)), "pulling back a thunk:")
+            test_approx(ad_cotangents, pullback(@thunk(ȳ)), "pulling back a thunk:"; isapprox_kwargs...)
             check_inferred && _test_inferred(pullback, @thunk(ȳ))
         end
     end  # top-level testset

test/testers.jl

@@ -683,7 +683,10 @@ end
         function ChainRulesCore.rrule(::typeof(my_id), x)
             my_id_pb(ȳ) = (NoTangent(), ȳ)
             function my_id_pb(ȳ::AbstractThunk)
-                precision = rand() > 0.5 ? Float64 : Float32
+                # We use a condition that always evaluates to true to avoid issues with tolerances
+                # (see https://github.com/JuliaDiff/ChainRulesTestUtils.jl/pull/247)
+                # The function is type unstable for `Float64` inputs nevertheless
+                precision = rand() >= 0.0 ? Float64 : Float32
                 return (NoTangent(), precision(unthunk(ȳ)))
             end
             return x, my_id_pb