Changed how ObjSense is represented to make it easier to print

Author: kwesiRutledge

problem/objective_sense.go

@@ -1,16 +1,18 @@
 package problem
 
-import "github.com/MatProGo-dev/MatProInterface.go/optim"
+import (
+	"github.com/MatProGo-dev/MatProInterface.go/optim"
+)
 
 // ObjSense represents whether an optimization objective is to be maximized or
 // minimized. This implementation conforms to the Gurobi encoding
-type ObjSense int
+type ObjSense string
 
 // Objective senses (minimize and maximize) encoding using Gurobi's standard
 const (
-	SenseMinimize ObjSense = 1
-	SenseMaximize          = -1
-	SenseFind     ObjSense = 0
+	SenseMinimize ObjSense = "Minimize"
+	SenseMaximize          = "Maximize"
+	SenseFind     ObjSense = "Find"
 )
 
 /*

testing/problem/objective_sense_test.go

@@ -1,9 +1,11 @@
 package problem_test
 
 import (
+	"fmt"
+	"testing"
+
 	"github.com/MatProGo-dev/MatProInterface.go/optim"
 	"github.com/MatProGo-dev/MatProInterface.go/problem"
-	"testing"
 )
 
 /*
@@ -52,3 +54,39 @@ func TestObjectiveSense_ToObjSense2(t *testing.T) {
 			problem.SenseMaximize, objSense)
 	}
 }
+
+/*
+TestObjectiveSense_String1
+Description:
+
+	Tests that we can extract strings from the three normal ObjSense values
+	(Minimize, Maximize, Find).
+*/
+func TestObjectiveSense_String1(t *testing.T) {
+	// Test Minimize
+	minSense := problem.SenseMinimize
+	if fmt.Sprintf("%v", minSense) != "Minimize" {
+		t.Errorf(
+			"minSense's string is \"%v\"; expected \"Minimize\"",
+			minSense,
+		)
+	}
+
+	// Test Maximize
+	maxSense := problem.SenseMaximize
+	if fmt.Sprintf("%v", maxSense) != "Maximize" {
+		t.Errorf(
+			"maxSense's string is \"%v\"; expected \"Maximize\"",
+			maxSense,
+		)
+	}
+
+	// Test Find
+	findSense := problem.SenseFind
+	if fmt.Sprintf("%v", findSense) != "Find" {
+		t.Errorf(
+			"findSense's string is \"%v\"; expected \"Find\"",
+			findSense,
+		)
+	}
+}