fix: localize validation errors and polish delivery

backend/pkg/validator/validator_test.go

@@ -1,8 +1,10 @@
 package validator
 
 import (
+	"fmt"
 	"testing"
 
+	"github.com/gin-gonic/gin/binding"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
@@ -137,6 +139,50 @@ func TestVar_AutoInit(t *testing.T) {
 	assert.NotNil(t, validate)
 }
 
+func TestValidateStruct_ReturnsLocalizedWrappedError(t *testing.T) {
+	type request struct {
+		Password string `json:"password" validate:"min=6"`
+	}
+
+	err := ValidateStruct(request{Password: "123"})
+	require.Error(t, err)
+	wrapped := fmt.Errorf("validation error: %w", err)
+	assert.True(t, IsValidationError(wrapped))
+	assert.Equal(t, "密码长度不能少于 6 个字符", ValidationMessage(wrapped))
+}
+
+func TestValidationMessage_LoginPasswordMin(t *testing.T) {
+	type loginRequest struct {
+		Password string `json:"password" binding:"required,min=6"`
+	}
+
+	err := binding.Validator.ValidateStruct(loginRequest{Password: "123"})
+	require.Error(t, err)
+	assert.True(t, IsValidationError(err))
+	assert.Equal(t, "密码长度不能少于 6 个字符", ValidationMessage(err))
+	assert.NotContains(t, err.Error(), "Field validation")
+}
+
+func TestValidationMessage_MultipleFields(t *testing.T) {
+	type request struct {
+		Email    string `json:"email" binding:"required,email"`
+		Password string `json:"password" binding:"required,min=6"`
+	}
+
+	err := binding.Validator.ValidateStruct(request{})
+	require.Error(t, err)
+	message := ValidationMessage(err)
+	assert.Contains(t, message, "请填写邮箱")
+	assert.Contains(t, message, "请填写密码")
+	assert.NotContains(t, message, "Key:")
+}
+
+func TestValidationMessageText_RemovesRawValidatorDetails(t *testing.T) {
+	raw := "Key: 'LoginRequest.Password' Error:Field validation for 'Password' failed on the 'min' tag"
+	assert.Equal(t, "请求参数不符合要求", ValidationMessageText(raw))
+	assert.Equal(t, "密码长度不能少于 6 个字符", ValidationMessageText("validation: 密码长度不能少于 6 个字符"))
+}
+
 func TestValidateStruct_Pointer(t *testing.T) {
 	Init()