feat: 添加映射和字段设置功能，支持结构体之间的转换

Author: TBXark

database/mapper/render.go

@@ -0,0 +1,77 @@
+package mapper
+
+import (
+	"encoding/json"
+	"fmt"
+	"golang.org/x/exp/constraints"
+	"reflect"
+	"strings"
+)
+
+func Map[S any, T any](source []S, mapper func(S) T) []T {
+	result := make([]T, len(source))
+	for i, s := range source {
+		result[i] = mapper(s)
+	}
+	return result
+}
+
+func MapStruct[S any, T any](source *S) *T {
+	bytes, err := json.Marshal(source)
+	if err != nil {
+		return nil
+	}
+	var target T
+	err = json.Unmarshal(bytes, &target)
+	if err != nil {
+		return nil
+	}
+	return &target
+}
+
+func SetFields[S any, T any](source S, target T, ignoreZero bool) (err error) {
+	defer func() {
+		if r := recover(); r != nil {
+			err = fmt.Errorf("panic: %v", r)
+		}
+	}()
+	sourceValue := reflect.ValueOf(source)
+	targetValue := reflect.ValueOf(target)
+	if targetValue.Kind() != reflect.Ptr {
+		err = fmt.Errorf("target must be a pointer")
+		return
+	}
+	targetValue = targetValue.Elem()
+	sourceType := sourceValue.Type()
+	for i := 0; i < sourceValue.NumField(); i++ {
+		field := sourceType.Field(i)
+		fieldValue := sourceValue.Field(i)
+		setterName := "Set" + strings.Title(field.Name)
+		method := targetValue.Addr().MethodByName(setterName)
+		if method.IsValid() {
+			args := []reflect.Value{fieldValue}
+			if ignoreZero && fieldValue.IsZero() {
+				continue
+			}
+			method.Call(args)
+		}
+	}
+	return
+}
+
+func Page[P constraints.Integer](total, pageSize, defaultSize P) P {
+	if total == 0 {
+		return 0
+	}
+	if pageSize == 0 {
+		pageSize = defaultSize
+	}
+	if pageSize == 0 {
+		return total
+	}
+	page := total / pageSize
+	if total%pageSize != 0 {
+		page++
+	}
+	return page
+}

database/mapper/render_test.go

@@ -0,0 +1,90 @@
+package mapper
+
+import (
+	"reflect"
+	"testing"
+)
+
+type Source struct {
+	Name     string
+	Age      int
+	IsActive bool
+}
+
+type Target struct {
+	name     *string
+	age      int
+	isActive bool
+}
+
+func (t *Target) SetName(name string)       { t.name = &name }
+func (t *Target) SetAge(age int)            { t.age = age }
+func (t *Target) SetIsActive(isActive bool) { t.isActive = isActive }
+
+func TestSetFields(t *testing.T) {
+	names := []string{"Alice", "", "Charlie"}
+	tests := []struct {
+		name       string
+		source     Source
+		ignoreZero bool
+		want       Target
+	}{
+		{
+			name: "Basic Test",
+			source: Source{
+				Name:     names[0],
+				Age:      25,
+				IsActive: true,
+			},
+			ignoreZero: false,
+			want: Target{
+				name:     &names[0],
+				age:      25,
+				isActive: true,
+			},
+		},
+		{
+			name: "Ignore zero value test",
+			source: Source{
+				Name:     names[1],
+				Age:      0,
+				IsActive: false,
+			},
+			ignoreZero: true,
+			want: Target{
+				name:     nil,
+				age:      0,
+				isActive: false,
+			},
+		},
+		{
+			name: "Partial field test",
+			source: Source{
+				Name:     names[2],
+				Age:      0,
+				IsActive: true,
+			},
+			ignoreZero: true,
+			want: Target{
+				name:     &names[2],
+				age:      0,
+				isActive: true,
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			target := &Target{}
+			err := SetFields(tt.source, target, tt.ignoreZero)
+			if err != nil {
+				t.Errorf("SetFields() error = %v", err)
+				return
+			}
+
+			if !reflect.DeepEqual(*target, tt.want) {
+				t.Errorf("SetFields() = %v, want %v", *target, tt.want)
+			}
+		})
+	}
+}