fix: make sure DataSample field cannot overlap with kwargs and extra

Author: BatyLeo

src/Utils/data_sample.jl

@@ -42,7 +42,9 @@ Constructor for `DataSample` with keyword arguments.
 All keyword arguments beyond `x`, `θ`, `y`, and `extra` are collected into the `maximizer_kwargs`
 field (solver kwargs). The `extra` keyword accepts a `NamedTuple` of non-solver data.
 
-Fields in `maximizer_kwargs` and `extra` must be disjoint. An error is thrown if they overlap.
+Fields in `maximizer_kwargs` and `extra` must be disjoint. Neither may use a reserved
+struct field name (`x`, `θ`, `y`, `maximizer_kwargs`, `extra`). An error is thrown in
+both cases.
 Both can be accessed directly via property forwarding.
 
 # Examples
@@ -69,6 +71,19 @@ function DataSample(; x=nothing, θ=nothing, y=nothing, extra=NamedTuple(), kwar
             "Keys $(collect(overlap)) appear in both maximizer_kwargs and extra of DataSample",
         )
     end
+    reserved = (:x, :θ, :y, :maximizer_kwargs, :extra)
+    shadowed_ctx = intersect(keys(maximizer_kwargs), reserved)
+    if !isempty(shadowed_ctx)
+        error(
+            "Keys $(collect(shadowed_ctx)) in maximizer_kwargs shadow DataSample struct fields",
+        )
+    end
+    shadowed_extra = intersect(keys(extra), reserved)
+    if !isempty(shadowed_extra)
+        error(
+            "Keys $(collect(shadowed_extra)) in extra shadow DataSample struct fields",
+        )
+    end
     return DataSample(x, θ, y, maximizer_kwargs, extra)
 end
 

src/Utils/interface.jl

@@ -547,6 +547,8 @@ meaning (whether uncertainty is independent of decisions).
 
 # Additional optional methods
 - [`generate_environment`](@ref)`(bench, rng)`: initialize a single rollout environment.
+  Must return an [`AbstractEnvironment`](@ref) (see `environment.jl` for the full protocol:
+  [`reset!`](@ref), [`observe`](@ref), [`step!`](@ref), [`is_terminated`](@ref)).
   Implement this instead of overriding [`generate_environments`](@ref) when environments
   can be drawn independently.
 - [`generate_baseline_policies`](@ref)`(bench)`: returns named baseline callables of
@@ -568,7 +570,7 @@ const ExogenousDynamicBenchmark = AbstractDynamicBenchmark{true}
 const EndogenousDynamicBenchmark = AbstractDynamicBenchmark{false}
 
 """
-    generate_environment(::AbstractDynamicBenchmark, rng::AbstractRNG; kwargs...)
+    generate_environment(::AbstractDynamicBenchmark, rng::AbstractRNG; kwargs...) -> AbstractEnvironment
 
 Initialize a single environment for the given dynamic benchmark.
 Primary implementation target for the count-based [`generate_environments`](@ref) default.