Add infeasible and unbounded tests

Author: kofgokhan

test/algorithms/Sandwiching.jl

@@ -101,6 +101,39 @@ function test_molp_2()
     return _test_molp(C, A, b, results, sense)
 end
 
+function test_infeasible()
+    model = MOA.Optimizer(HiGHS.Optimizer)
+    MOI.set(model, MOA.Algorithm(), MOA.Sandwiching(0.0))
+    MOI.set(model, MOI.Silent(), true)
+    x = MOI.add_variables(model, 2)
+    MOI.add_constraint.(model, x, MOI.GreaterThan(0.0))
+    MOI.add_constraint(model, 1.0 * x[1] + 1.0 * x[2], MOI.LessThan(-1.0))
+    MOI.set(model, MOI.ObjectiveSense(), MOI.MIN_SENSE)
+    f = MOI.Utilities.operate(vcat, Float64, 1.0 .* x...)
+    MOI.set(model, MOI.ObjectiveFunction{typeof(f)}(), f)
+    MOI.optimize!(model)
+    @test MOI.get(model, MOI.TerminationStatus()) == MOI.INFEASIBLE
+    @test MOI.get(model, MOI.PrimalStatus()) == MOI.NO_SOLUTION
+    @test MOI.get(model, MOI.DualStatus()) == MOI.NO_SOLUTION
+    return
+end
+
+function test_unbounded()
+    model = MOA.Optimizer(HiGHS.Optimizer)
+    MOI.set(model, MOA.Algorithm(), MOA.Sandwiching(0.0))
+    MOI.set(model, MOI.Silent(), true)
+    x = MOI.add_variables(model, 2)
+    MOI.add_constraint.(model, x, MOI.GreaterThan(0.0))
+    f = MOI.Utilities.operate(vcat, Float64, 1.0 .* x...)
+    MOI.set(model, MOI.ObjectiveFunction{typeof(f)}(), f)
+    MOI.set(model, MOI.ObjectiveSense(), MOI.MAX_SENSE)
+    MOI.optimize!(model)
+    @test MOI.get(model, MOI.TerminationStatus()) == MOI.DUAL_INFEASIBLE
+    @test MOI.get(model, MOI.PrimalStatus()) == MOI.NO_SOLUTION
+    @test MOI.get(model, MOI.DualStatus()) == MOI.NO_SOLUTION
+    return
+end
+
 end  # TestSandwiching
 
 TestSandwiching.run_tests()