Merge pull request #734 from jonathanfischer97/fix_pop_save

Reversion: stop deep copying population, just save `curr_u` for `OptimizationState` construction

Author: Vaibhavdixit02

lib/OptimizationEvolutionary/src/OptimizationEvolutionary.jl

@@ -21,8 +21,8 @@ function Evolutionary.trace!(tr, iteration, objfun, state, population,
     dt = Dict{String, Any}()
     dt["time"] = curr_time
 
-    # record `x` to store the population. Needed for constructing OptimizationState.
-    dt["x"] = deepcopy(population)
+    # record current u0. Needed for constructing OptimizationState.
+    dt["curr_u"] = population[end]
 
     # set additional trace value
     Evolutionary.trace!(dt, objfun, state, population, method, options)
@@ -105,7 +105,7 @@ function SciMLBase.__solve(cache::OptimizationCache{
     cur, state = iterate(cache.data)
 
     function _cb(trace)
-        curr_u = decompose_trace(trace).metadata["x"][end]
+        curr_u = decompose_trace(trace).metadata["curr_u"]
         opt_state = Optimization.OptimizationState(;
             iter = decompose_trace(trace).iteration,
             u = curr_u,

lib/OptimizationEvolutionary/test/runtests.jl

@@ -53,10 +53,7 @@ Random.seed!(1234)
     # Test that `store_trace=true` works now. Threw ""type Array has no field value" before.
     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.
+    # Make sure that both the user's trace record value, as well as `curr_u` are stored in the trace.
     @test haskey(sol.original.trace[end].metadata, "TESTVAL") &&
-          haskey(sol.original.trace[end].metadata, "x")
-
-    # Test the the values of x are saved, not the reference
-    @test !(sol.original.trace[end].metadata["x"] === sol.original.trace[end-1].metadata["x"])
+          haskey(sol.original.trace[end].metadata, "curr_u")
 end