Error when trying to query objective value with CPLEX

[bcdandurand]

I'm using the current version of JuMP, v0.20.0

I have the following simple code snippet where both CPLEX and Ipopt can be used:

 using JuMP
 using CPLEX, Ipopt

  mTest = Model(with_optimizer(CPLEX.Optimizer))
  #mTest = Model(with_optimizer(Ipopt.Optimizer))
  @variable(mTest, x)
  @variable(mTest, y)
  @objective(mTest, Min, (x-3)^2 + (y+2)^2)
  println(mTest)
  optimize!(mTest)
  println("Status: ",JuMP.termination_status(mTest))
  println("(x,y)=",JuMP.value(x)," ",JuMP.value(y))
  println("obj val: ",JuMP.objective_value(mTest))
  println("It works!")

When I run the code, it computes the correct optimal solution, but then I get the error when querying the objective value. The code works fine when using Ipopt, so I'm not sure if this is an issue with JuMP or with CPLEX.jl

Status: OPTIMAL
(x,y)=2.9999999996524593 -2.0000000000011937
ERROR: LoadError: type ObjectiveValue has no field resultindex
Stacktrace:
[1] getproperty(::Any, ::Symbol) at ./Base.jl:20
[2] get(::CPLEX.Optimizer, ::MathOptInterface.ObjectiveValue) at /homes/bcdandurand/.julia/packages/LinQuadOptInterface/ZMx9f/src/solve.jl:107
[3] get(::MathOptInterface.Bridges.LazyBridgeOptimizer{CPLEX.Optimizer}, ::MathOptInterface.ObjectiveValue) at /homes/bcdandurand/.julia/packages/MathOptInterface/016Ol/src/Bridges/bridge_optimizer.jl:444
[4] get(::MathOptInterface.Utilities.CachingOptimizer{MathOptInterface.AbstractOptimizer,MathOptInterface.Utilities.UniversalFallback{MathOptInterface.Utilities.Model{Float64}}}, ::MathOptInterface.ObjectiveValue) at /homes/bcdandurand/.julia/packages/MathOptInterface/016Ol/src/Utilities/cachingoptimizer.jl:449
[5] _moi_get_result(::MathOptInterface.Utilities.CachingOptimizer{MathOptInterface.AbstractOptimizer,MathOptInterface.Utilities.UniversalFallback{MathOptInterface.Utilities.Model{Float64}}}, ::MathOptInterface.ObjectiveValue) at /homes/bcdandurand/.julia/packages/JuMP/iGamg/src/JuMP.jl:605
[6] get(::Model, ::MathOptInterface.ObjectiveValue) at /homes/bcdandurand/.julia/packages/JuMP/iGamg/src/JuMP.jl:618
[7] objective_value(::Model) at /homes/bcdandurand/.julia/packages/JuMP/iGamg/src/objective.jl:25
[8] top-level scope at /nfs2/bcdandurand/OPF-VID/test_opt.jl:14
[9] include at ./boot.jl:328 [inlined]
[10] include_relative(::Module, ::String) at ./loading.jl:1094
[11] include(::Module, ::String) at ./Base.jl:31
[12] exec_options(::Base.JLOptions) at ./client.jl:295
[13] _start() at ./client.jl:464
in expression starting at /nfs2/bcdandurand/OPF-VID/test_opt.jl:14

[blegat]

CPLEX has not been updated to MOI v0.9 yet, which is the version of the interface used by JuMP, it is currently been updated here: jump-dev/CPLEX.jl#250

[mlubin]

The bug is that Pkg allowed you to install CPLEX and JuMP 0.20. This will be fixed by JuliaRegistries/General#2971.