comparisons and booleans

vm/vm_test.go

@@ -48,6 +48,12 @@ func testExpectedObject(t *testing.T, expected interface{}, actual object.Object
 		if err != nil {
 			t.Errorf("testIntegerObject failed: %s", err)
 		}
+
+	case bool:
+		err := testBooleanObject(bool(expected), actual)
+		if err != nil {
+			t.Errorf("testBooleanObject failed: %s", err)
+		}
 	}
 }
 
@@ -70,6 +76,19 @@ func testIntegerObject(expected int64, actual object.Object) interface{} {
 	return nil
 }
 
+func testBooleanObject(expected bool, actual object.Object) interface{} {
+	result, ok := actual.(*object.Boolean)
+	if !ok {
+		return fmt.Errorf("object is not Boolean. got=%T (%+v", actual, actual)
+	}
+
+	if result.Value != expected {
+		return fmt.Errorf("object has wrong value. got=%t, want=%t", result.Value, expected)
+	}
+
+	return nil
+}
+
 func TestIntegerArithmetic(t *testing.T) {
 	tests := []vmTestCase{
 		{"1", 1},
@@ -83,6 +102,32 @@ func TestIntegerArithmetic(t *testing.T) {
 		{"5 * 2 + 10", 20},
 		{"5 + 2 * 10", 25},
 		{"5 * (2 + 10)", 60},
+		{"1 < 2", true},
+		{"1 > 2", false},
+		{"1 < 1", false},
+		{"1 > 1", false},
+		{"1 == 1", true},
+		{"1 != 1", false},
+		{"1 == 2", false},
+		{"1 != 2", true},
+		{"true == true", true},
+		{"false == false", true},
+		{"true == false", false},
+		{"true != false", true},
+		{"false != true", true},
+		{"(1 < 2) == true", true},
+		{"(1 < 2) == false", false},
+		{"(1 > 2) == true", false},
+		{"(1 > 2) == false", true},
+	}
+
+	runVmTests(t, tests)
+}
+
+func TestBooleanExpressions(t *testing.T) {
+	tests := []vmTestCase{
+		{"true", true},
+		{"false", false},
 	}
 
 	runVmTests(t, tests)