You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: gpool_z_unit_test.go
    path of file: ./repos/gf/container/gpool
    
    the code of the file until where you have to start completion: // Copyright GoFrame Author(https://goframe.org). All Rights Reserved.
//
// This Source Code Form is subject to the terms of the MIT License.
// If a copy of the MIT was not distributed with this file,
// You can obtain one at https://github.com/gogf/gf.

package gpool_test

import (
	"errors"
	"testing"
	"time"

	"github.com/gogf/gf/v2/container/gpool"
	"github.com/gogf/gf/v2/frame/g"
	"github.com/gogf/gf/v2/test/gtest"
)

var nf gpool.NewFunc = func() (i interface{}, e error) {
	return "hello", nil
}

var assertIndex int = 0

var ef gpool.ExpireFunc = func(i interface{}) {
	assertIndex++
	gtest.Assert(i, assertIndex)
}

func Test_Gpool(t *testing.T) {
	gtest.C(t, func(t *gtest.T) {
		//
		// expire = 0
		p1 := gpool.New(0, nf)
		p1.Put(1)
		p1.Put(2)
		time.Sleep(1 * time.Second)
		// test won't be timeout
		v1, err1 :
    
func Test_Gpool(t *testing.T) {
	gtest.C(t, func(t *gtest.T) {
		//
		// expire = 0
		p1 := gpool.New(0, nf)
		p1.Put(1)
		p1.Put(2)
		time.Sleep(1 * time.Second)
		// test won't be timeout
		v1, err1 := p1.Get()
		t.Assert(err1, nil)
		t.AssertIN(v1, g.Slice{1, 2})
		// test clear
		p1.Clear()
		t.Assert(p1.Size(), 0)
		// test newFunc
		v1, err1 = p1.Get()
		t.Assert(err1, nil)
		t.Assert(v1, "hello")
		// put data again
		p1.Put(3)
		p1.Put(4)
		v1, err1 = p1.Get()
		t.Assert(err1, nil)
		t.AssertIN(v1, g.Slice{3, 4})
		// test close
		p1.Close()
		v1, err1 = p1.Get()
		t.Assert(err1, nil)
		t.Assert(v1, "hello")
	})

	gtest.C(t, func(t *gtest.T) {
		//
		// expire > 0
		p2 := gpool.New(2*time.Second, nil, ef)
		for index := 0; index < 10; index++ {
			p2.Put(index)
		}
		t.Assert(p2.Size(), 10)
		v2, err2 := p2.Get()
		t.Assert(err2, nil)
		t.Assert(v2, 0)
		// test timeout expireFunc
		time.Sleep(3 * time.Second)
		v2, err2 = p2.Get()
		t.Assert(err2, errors.New("pool is empty"))
		t.Assert(v2, nil)
		// test close expireFunc
		for index := 0; index < 10; index++ {
			p2.Put(index)
		}
		t.Assert(p2.Size(), 10)
		v2, err2 = p2.Get()
		t.Assert(err2, nil)
		t.Assert(v2, 0)
		assertIndex = 0
		p2.Close()
		time.Sleep(3 * time.Second)
		t.AssertNE(p2.Put(1), nil)
	})

	gtest.C(t, func(t *gtest.T) {
		//
		// expire < 0
		p3 := gpool.New(-1, nil)
		v3, err3 := p3.Get()
		t.Assert(err3, errors.New("pool is empty"))
		t.Assert(v3, nil)
	})

	gtest.C(t, func(t *gtest.T) {
		p := gpool.New(time.Millisecond*200, nil, func(i interface{}) {})
		p.Put(1)
		time.Sleep(time.Millisecond * 100)
		p.Put(2)
		time.Sleep(time.Millisecond * 200)
	})

	gtest.C(t, func(t *gtest.T) {
		s := make([]int, 0)
		p := gpool.New(time.Millisecond*200, nil, func(i interface{}) {
			s = append(s, i.(int))
		})
		for i := 0; i < 5; i++ {
			p.Put(i)
			time.Sleep(time.Millisecond * 50)
		}
		val, err := p.Get()
		t.Assert(val, 2)
		t.AssertNil(err)
		t.Assert(p.Size(), 2)
	})
}