Add new array support

features/array.feature

@@ -0,0 +1,11 @@
+Feature: Array
+
+  Scenario: Create a new array
+    When I execute ruby code:
+      """
+      [1, "str", 3]
+      """
+    Then there should return an array
+    """
+    [1 str 3]
+    """

godogs_test.go

@@ -141,6 +141,24 @@ func (feat *RubyFeature) thereShouldReturnModule(expected string) error {
 	return nil
 }
 
+func (feat *RubyFeature) thereShouldReturnAnArray(doc *godog.DocString) error {
+	actual, ok := feat.ret.([]mruby.Value)
+
+	if !ok {
+		return fmt.Errorf("expected array, got %T", feat.ret)
+	}
+
+	actualStr := fmt.Sprintf("%+v", actual)
+	expectedStr := doc.Content
+
+	if !cmp.Equal(actualStr, expectedStr) {
+		return fmt.Errorf("array not matched %s", cmp.Diff(actual, expectedStr))
+
+	}
+
+	return nil
+}
+
 func (feat *RubyFeature) theExceptionMessageShouldBe(expected string) error {
 	exc, ok := feat.ret.(mruby.RException)
 
@@ -176,6 +194,7 @@ func InitializeScenario(s *godog.ScenarioContext) {
 	s.Step(`^there should return object$`, feat.thereShouldReturnObject)
 	s.Step(`^there should return class "([^"]*)"$`, feat.thereShouldReturnClass)
 	s.Step(`^there should return module "([^"]*)"$`, feat.thereShouldReturnModule)
+	s.Step(`^there should return an array$`, feat.thereShouldReturnAnArray)
 	s.Step(`^the exception message should be "([^"]*)"$`, feat.theExceptionMessageShouldBe)
 }
 

stack/stack.go

@@ -61,7 +61,10 @@ func (s *Stack[T]) Slice(start, end int) []T {
 		end = s.end
 	}
 
-	return s.elements[start:end]
+	subset := make([]T, end-start)
+	copy(subset, s.elements[start:end])
+
+	return subset
 }
 
 func (s *Stack[T]) Get(idx int) T {

vm.go

@@ -244,6 +244,14 @@ func (mrb *State) VmExec(proc RProc, code *insn.Sequence) (ret Value, err error)
 			}
 
 			ctx.Set(int(a), res)
+		case op.Array:
+			a := code.ReadB()
+			b := code.ReadB()
+
+			begin := int(a)
+			end := int(a) + int(b) - 1
+
+			ctx.Set(int(a), ctx.Slice(begin, end))
 		case op.String:
 			a := code.ReadB()
 			b := code.ReadB()