Merge pull request #702 from jonathanfischer97/fix_trace!

fixed user `trace!` overload compat. Both `x` and user records now saved

Author: Vaibhavdixit02

lib/OptimizationEvolutionary/src/OptimizationEvolutionary.jl

@@ -11,9 +11,25 @@ SciMLBase.supports_opt_cache_interface(opt::Evolutionary.AbstractOptimizer) = tr
 decompose_trace(trace::Evolutionary.OptimizationTrace) = last(trace)
 decompose_trace(trace::Evolutionary.OptimizationTraceRecord) = trace
 
-function Evolutionary.trace!(record::Dict{String, Any}, objfun, state, population,
-        method::Evolutionary.AbstractOptimizer, options)
-    record["x"] = population
+# Overload the trace! function to add the population to the trace prior to calling any user-defined trace! method
+function Evolutionary.trace!(tr, iteration, objfun, state, population, method::Evolutionary.AbstractOptimizer, options, curr_time=time()) 
+    dt = Dict{String,Any}()
+    dt["time"] = curr_time
+
+    # record `x` to store the population. Needed for constructing OptimizationState.
+    dt["x"] = population
+
+    # set additional trace value
+    Evolutionary.trace!(dt, objfun, state, population, method, options)
+    Evolutionary.update!(tr,
+            state,
+            iteration,
+            Evolutionary.value(state),
+            dt,
+            options.store_trace,
+            options.show_trace,
+            options.show_every,
+            options.callback)
 end
 
 function __map_optimizer_args(cache::OptimizationCache,

lib/OptimizationEvolutionary/test/runtests.jl

@@ -41,8 +41,17 @@ Random.seed!(1234)
         end
         return false
     end
-    sol = solve(prob, CMAES(μ = 40, λ = 100), callback = cb, maxiters = 100)
+    solve(prob, CMAES(μ = 40, λ = 100), callback = cb, maxiters = 100)
 
+    # Test compatibility of user overload of trace! 
+    function Evolutionary.trace!(record::Dict{String, Any}, objfun, state, population, method::CMAES, options)
+        # record fittest individual
+        record["TESTVAL"] = state.fittest
+    end
+
     #test that `store_trace=true` works now. Threw ""type Array has no field value" before.
-    solve(prob, CMAES(μ = 40, λ = 100), store_trace = true)
+    sol = solve(prob, CMAES(μ = 40, λ = 100), store_trace = true)
+
+    # Make sure that both the user's trace record value, as well as `x` are stored in the trace.
+    @test haskey(sol.original.trace[end].metadata, "TESTVAL") &&  haskey(sol.original.trace[end].metadata, "x")
 end