Check if config is nothing before accessing fields

Project.toml

@@ -1,7 +1,7 @@
 name = "Mooncake"
 uuid = "da2b9cff-9c12-43a0-ae48-6db2b0edb7d6"
 authors = ["Will Tebbutt, Hong Ge, and contributors"]
-version = "0.4.5"
+version = "0.4.6"
 
 [deps]
 ADTypes = "47edcb42-4c32-4615-8424-f2b9edc5f35b"

ext/MooncakeLogDensityProblemsADExt.jl

@@ -59,8 +59,12 @@ function logdensity_and_gradient(∇l::MooncakeGradientLogDensity, x::Vector{Flo
 end
 
 # Interop with ADTypes.
+function getconfig(x::ADTypes.AutoMooncake)
+ c = x.config
+ isnothing(c) ? Mooncake.DEFAULT_CONFIG : c
+end
 function ADgradient(x::ADTypes.AutoMooncake, ℓ)
- debug_mode = x.config.debug_mode
+ debug_mode = getconfig(x).debug_mode
  if debug_mode
  msg = "Running Mooncake in debug mode. This mode is computationally expensive, " *
  "should only be used when debugging a problem with AD, and turned off in " *

src/config.jl

@@ -7,3 +7,5 @@ Configuration struct for use with ADTypes.AutoMooncake.
  debug_mode::Bool=false
  silence_debug_messages::Bool=false
 end
+
+const DEFAULT_CONFIG = Config()

test/config.jl

@@ -1,4 +1,4 @@
 @testset "config" begin
- @test !Mooncake.Config().debug_mode
- @test !Mooncake.Config().silence_debug_messages
+ @test !Mooncake.DEFAULT_CONFIG.debug_mode
+ @test !Mooncake.DEFAULT_CONFIG.silence_debug_messages
 end