feat: strings add json string func

pkg/stringx/strings.go

@@ -1,6 +1,7 @@
 package stringx
 
 import (
+	"encoding/json"
 	"errors"
 	"strings"
 )
@@ -119,3 +120,16 @@ func TakeOne(valid, or string) string {
 
 	return or
 }
+
+// MustJsonString returns string from json.Marshal.
+func MustJsonString(obj interface{}) string {
+	if obj == nil {
+		return ""
+	}
+
+	b, err := json.Marshal(obj)
+	if err != nil {
+		return ""
+	}
+	return string(b)
+}

pkg/stringx/strings_test.go

@@ -297,3 +297,22 @@ func TestTakeOne(t *testing.T) {
 		})
 	}
 }
+
+func TestMustJsonString(t *testing.T) {
+	tests := []struct {
+		name string
+		obj  interface{}
+		want string
+	}{
+		{"empty", "", `""`},
+		{"nil", nil, ``},
+		{"map", map[string]int{"a": 1}, `{"a":1}`},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := MustJsonString(tt.obj); got != tt.want {
+				t.Errorf("MustJsonString() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}