feat: read the structure to increase the judgment of the omitempty op… (#2529)

* feat: read the structure to increase the judgment of the omitempty option, the same as json

Signed-off-by: monkey92t <golang@88.com>

commands.go

@@ -106,20 +106,55 @@ func appendStructField(dst []interface{}, v reflect.Value) []interface{} {
 		if tag == "" || tag == "-" {
 			continue
 		}
-		tag = strings.Split(tag, ",")[0]
-		if tag == "" {
+		name, opt, _ := strings.Cut(tag, ",")
+		if name == "" {
 			continue
 		}
 
 		field := v.Field(i)
+
+		// miss field
+		if omitEmpty(opt) && isEmptyValue(field) {
+			continue
+		}
+
 		if field.CanInterface() {
-			dst = append(dst, tag, field.Interface())
+			dst = append(dst, name, field.Interface())
 		}
 	}
 
 	return dst
 }
 
+func omitEmpty(opt string) bool {
+	for opt != "" {
+		var name string
+		name, opt, _ = strings.Cut(opt, ",")
+		if name == "omitempty" {
+			return true
+		}
+	}
+	return false
+}
+
+func isEmptyValue(v reflect.Value) bool {
+	switch v.Kind() {
+	case reflect.Array, reflect.Map, reflect.Slice, reflect.String:
+		return v.Len() == 0
+	case reflect.Bool:
+		return !v.Bool()
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return v.Int() == 0
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		return v.Uint() == 0
+	case reflect.Float32, reflect.Float64:
+		return v.Float() == 0
+	case reflect.Interface, reflect.Pointer:
+		return v.IsNil()
+	}
+	return false
+}
+
 type Cmdable interface {
 	Pipeline() Pipeliner
 	Pipelined(ctx context.Context, fn func(Pipeliner) error) ([]Cmder, error)

commands_test.go

@@ -2136,6 +2136,7 @@ var _ = Describe("Commands", func() {
 				Set3 time.Duration          `redis:"set3"`
 				Set4 interface{}            `redis:"set4"`
 				Set5 map[string]interface{} `redis:"-"`
+				Set6 string                 `redis:"set6,omitempty"`
 			}
 
 			hSet = client.HSet(ctx, "hash", &set{
@@ -2148,13 +2149,29 @@ var _ = Describe("Commands", func() {
 			Expect(hSet.Err()).NotTo(HaveOccurred())
 			Expect(hSet.Val()).To(Equal(int64(4)))
 
-			hMGet := client.HMGet(ctx, "hash", "set1", "set2", "set3", "set4")
+			hMGet := client.HMGet(ctx, "hash", "set1", "set2", "set3", "set4", "set5", "set6")
 			Expect(hMGet.Err()).NotTo(HaveOccurred())
 			Expect(hMGet.Val()).To(Equal([]interface{}{
 				"val1",
 				"1024",
 				strconv.Itoa(int(2 * time.Millisecond.Nanoseconds())),
 				"",
+				nil,
+				nil,
+			}))
+
+			hSet = client.HSet(ctx, "hash2", &set{
+				Set1: "val2",
+				Set6: "val",
+			})
+			Expect(hSet.Err()).NotTo(HaveOccurred())
+			Expect(hSet.Val()).To(Equal(int64(5)))
+
+			hMGet = client.HMGet(ctx, "hash2", "set1", "set6")
+			Expect(hMGet.Err()).NotTo(HaveOccurred())
+			Expect(hMGet.Val()).To(Equal([]interface{}{
+				"val2",
+				"val",
 			}))
 		})