1 files changed, 83 insertions, 0 deletions

diff --git a/subprojects/store-reasoning-scope/src/test/java/tools/refinery/store/reasoning/scope/MPSolverTest.java b/subprojects/store-reasoning-scope/src/test/java/tools/refinery/store/reasoning/scope/MPSolverTest.java
new file mode 100644
index 00000000..95c4ac68
--- /dev/null
+++ b/subprojects/store-reasoning-scope/src/test/java/tools/refinery/store/reasoning/scope/MPSolverTest.java
@@ -0,0 +1,83 @@
+/*
+ * SPDX-FileCopyrightText: 2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.reasoning.scope;
+
+import com.google.ortools.Loader;
+import com.google.ortools.linearsolver.MPSolver;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.closeTo;
+import static org.hamcrest.Matchers.is;
+
+class MPSolverTest {
+        @BeforeAll
+        static void beforeAll() {
+                Loader.loadNativeLibraries();
+        }
+
+        @Test
+        void updateProblemTest() {
+                var solver = MPSolver.createSolver("GLOP");
+                var x = solver.makeNumVar(0, Double.POSITIVE_INFINITY, "x");
+                var y = solver.makeNumVar(0, 1, "y");
+                var constraint = solver.makeConstraint(5, 5);
+                constraint.setCoefficient(x, 1);
+                constraint.setCoefficient(y, 1);
+                var objective = solver.objective();
+
+                objective.setCoefficient(x, 1);
+                objective.setMinimization();
+                assertThat(solver.solve(), is(MPSolver.ResultStatus.OPTIMAL));
+                assertThat(objective.value(), closeTo(4, 0.01));
+
+                objective.setMaximization();
+                assertThat(solver.solve(), is(MPSolver.ResultStatus.OPTIMAL));
+                assertThat(objective.value(), closeTo(5, 0.01));
+
+                objective.setCoefficient(x, 0);
+                objective.setCoefficient(y, 1);
+                objective.setMinimization();
+                assertThat(solver.solve(), is(MPSolver.ResultStatus.OPTIMAL));
+                assertThat(objective.value(), closeTo(0, 0.01));
+
+                objective.setMaximization();
+                assertThat(solver.solve(), is(MPSolver.ResultStatus.OPTIMAL));
+                assertThat(objective.value(), closeTo(1, 0.01));
+        }
+
+        @Test
+        void unboundedIsInfeasibleTest() {
+                var solver = MPSolver.createSolver("GLOP");
+                var x = solver.makeNumVar(0, Double.POSITIVE_INFINITY, "x");
+                var objective = solver.objective();
+                objective.setCoefficient(x, 1);
+
+                objective.setMinimization();
+                assertThat(solver.solve(), is(MPSolver.ResultStatus.OPTIMAL));
+                assertThat(objective.value(), closeTo(0, 0.01));
+
+                objective.setMaximization();
+                assertThat(solver.solve(), is(MPSolver.ResultStatus.INFEASIBLE));
+        }
+
+        @Test
+        void constantTest() {
+                var solver = MPSolver.createSolver("GLOP");
+                var x = solver.makeNumVar(1, 1, "x");
+                var objective = solver.objective();
+                objective.setCoefficient(x, 1);
+
+                objective.setMinimization();
+                assertThat(solver.solve(), is(MPSolver.ResultStatus.OPTIMAL));
+                assertThat(objective.value(), closeTo(1, 0.01));
+
+                objective.setMaximization();
+                assertThat(solver.solve(), is(MPSolver.ResultStatus.OPTIMAL));
+                assertThat(objective.value(), closeTo(1, 0.01));
+        }
+}