Fix FiniteDiff Hessian cache (#185)

Author: gdalle

DifferentiationInterface/Project.toml

@@ -49,7 +49,7 @@ DocStringExtensions = "0.9.3"
 Enzyme = "0.11.20"
 FastDifferentiation = "0.3.7"
 FillArrays = "1.9.3"
-FiniteDiff = "2.23.0"
+FiniteDiff = "2.23.1"
 FiniteDifferences = "0.12.31"
 ForwardDiff = "0.10.36"
 LinearAlgebra = "1"

DifferentiationInterface/ext/DifferentiationInterfaceFiniteDiffExt/onearg.jl

@@ -178,9 +178,9 @@ end
 # cache cannot be reused because of https://github.com/JuliaDiff/FiniteDiff.jl/issues/185
 
 function DI.hessian(f, backend::AutoFiniteDiff, x, extras::FiniteDiffHessianExtras)
-    return finite_difference_hessian(f, x, HessianCache(x, fdhtype(backend)))
+    return finite_difference_hessian(f, x, extras.cache)
 end
 
 function DI.hessian!(f, hess, backend::AutoFiniteDiff, x, extras::FiniteDiffHessianExtras)
-    return finite_difference_hessian!(hess, f, x, HessianCache(x, fdhtype(backend)))
+    return finite_difference_hessian!(hess, f, x, extras.cache)
 end