modified omikuji map to slice

kadai4/main.go

@@ -22,15 +22,7 @@ func handler(w http.ResponseWriter, r *http.Request) {
 	w.Header().Set("Content-Type", "application/json; charset=utf-8")
 
 	omikuji := omikuji.Omikuji{time.Now()}
-	ret, err := omikuji.Do()
-	res := Response{}
-
-	if err != nil {
-		res.Msg = err.Error()
-		log.Println("Error:", err)
-	} else {
-		res.Msg = ret
-	}
+	res := Response{omikuji.Do()}
 
 	if err := json.NewEncoder(w).Encode(res); err != nil {
 		log.Println("Error:", err)

kadai4/omikuji/omikuji.go

@@ -1,18 +1,17 @@
 package omikuji
 
 import (
-	"fmt"
 	"math/rand"
 	"time"
 )
 
-var omikuji = map[int]string{
-	0: "凶",
-	1: "末吉",
-	2: "小吉",
-	3: "中吉",
-	4: "吉",
-	5: "大吉",
+var omikuji = []string{
+	"凶",
+	"末吉",
+	"小吉",
+	"中吉",
+	"吉",
+	"大吉",
 }
 
 type Omikuji struct {
@@ -23,29 +22,15 @@ func (o *Omikuji) SetSeed(seed int64) {
 	rand.Seed(seed)
 }
 
-type OmikujiError struct {
-	Msg string
-}
-
-func (err *OmikujiError) Error() string {
-	return fmt.Sprintf(err.Msg)
-}
-
-func (o *Omikuji) Do() (string, error) {
+func (o *Omikuji) Do() string {
 	var i int
 
 	_, m, d := o.Time.Date()
 	// 1/1 ~ 1/3のみ大吉を出す
 	if int(m) == 1 && d >= 1 && d <= 3 {
-		i = 5
-	} else {
-		i = rand.Intn(len(omikuji))
-	}
-
-	s, ok := omikuji[i]
-	if !ok {
-		return "", &OmikujiError{"おみくじが引けませんでした。"}
+		return "大吉"
 	}
 
-	return s, nil
+	i = rand.Intn(len(omikuji))
+	return omikuji[i]
 }

kadai4/omikuji/omikuji_test.go

@@ -11,7 +11,7 @@ func Test_NormalTime(t *testing.T) {
 	time := time.Date(2019, time.Month(8), 16, 0, 0, 0, 0, time.Local)
 	omikuji := omikuji.Omikuji{time}
 	expect := "大吉"
-	actual, _ := omikuji.Do()
+	actual := omikuji.Do()
 	if expect != actual {
 		t.Errorf(`Omikuji error: expect="%s" actual="%s"`, expect, actual)
 	}
@@ -28,7 +28,7 @@ func Test_SpecificPeriod(t *testing.T) {
 		for _, d := range days {
 			time := time.Date(2019, time.Month(m), d, 0, 0, 0, 0, time.Local)
 			omikuji := omikuji.Omikuji{time}
-			actual, _ := omikuji.Do()
+			actual := omikuji.Do()
 			if expect != actual {
 				t.Errorf(`Omikuji error: expect="%s" actual="%s"`, expect, actual)
 			}