From 596d32e09d6c4b0461ddd9e32e4461a924b9af19 Mon Sep 17 00:00:00 2001
From: Shadi Akiki <shadiakiki1986@gmail.com>
Date: Mon, 2 Nov 2020 15:34:21 +0200
Subject: [PATCH] add unit test for calling optimize twice

---
 src/Test/UnitTests/solve.jl | 15 +++++++++++++++
 test/Test/unit.jl           | 17 +++++++++++++++++
 2 files changed, 32 insertions(+)

diff --git a/src/Test/UnitTests/solve.jl b/src/Test/UnitTests/solve.jl
index b26de21fba..3c73c3b4d1 100644
--- a/src/Test/UnitTests/solve.jl
+++ b/src/Test/UnitTests/solve.jl
@@ -172,3 +172,18 @@ function solve_result_index(model::MOI.ModelLike, config::TestConfig)
     end
 end
 unittests["solve_result_index"] = solve_result_index
+
+function solve_twice(model::MOI.ModelLike, config::TestConfig)
+    MOI.empty!(model)
+    x = MOI.add_variable(model)
+    c = MOI.add_constraint(model, MOI.SingleVariable(x), MOI.GreaterThan(1.0))
+    MOI.set(model, MOI.ObjectiveSense(), MOI.MIN_SENSE)
+    MOI.set(model, MOI.ObjectiveFunction{MOI.SingleVariable}(), MOI.SingleVariable(x))
+    if config.solve
+        MOI.optimize!(model)
+        MOI.optimize!(model)
+        MOI.get(model, MOI.TerminationStatus()) == MOI.OPTIMAL
+        MOI.get(model, MOI.VariablePrimal(), x) == 1.0
+    end
+end
+unittests["solve_twice"] = solve_twice
diff --git a/test/Test/unit.jl b/test/Test/unit.jl
index 210286e130..5596d802e3 100644
--- a/test/Test/unit.jl
+++ b/test/Test/unit.jl
@@ -49,6 +49,7 @@ end
             "solve_single_variable_dual_min",
             "solve_single_variable_dual_max",
             "solve_result_index",
+            "solve_twice",
             ])
         MOI.empty!(model)
     end
@@ -392,6 +393,22 @@ end
         )
         MOIT.solve_result_index(mock, config)
     end
+
+    @testset "solve_twice" begin
+        MOIU.set_mock_optimize!(mock,
+            (mock::MOIU.MockOptimizer) -> MOIU.mock_optimize!(
+                mock,
+                MOI.OPTIMAL,
+                (MOI.FEASIBLE_POINT, [1.0]),
+            ),
+            (mock::MOIU.MockOptimizer) -> MOIU.mock_optimize!(
+                mock,
+                MOI.OPTIMAL,
+                (MOI.FEASIBLE_POINT, [1.0]),
+            )
+        )
+        MOIT.solve_twice(mock, config)
+    end
 end
 
 @testset "modifications" begin