如何使用Golang测试结构体方法

package main

type Account struct {
    balance float64
}

func (a *Account) Deposit(amount float64) {
    if amount > 0 {
        a.balance += amount
    }
}

func (a *Account) Balance() float64 {
    return a.balance
}

package main

import (
    "testing"
)

func TestAccount_Deposit(t *testing.T) {
    acc := &Account{balance: 100}
    acc.Deposit(50)

    if acc.Balance() != 150 {
        t.Errorf("期望余额 150，实际 %f", acc.Balance())
    }

    // 测试非法存款
    acc.Deposit(-10)
    if acc.Balance() != 150 {
        t.Errorf("负数存款不应修改余额，当前余额 %f", acc.Balance())
    }
}

go test -v

func (a Account) String() string {
    return fmt.Sprintf("余额: %.2f", a.balance)
}

func TestAccount_String(t *testing.T) {
    acc := &Account{balance: 99.5}
    expected := "余额: 99.50"
    if acc.String() != expected {
        t.Errorf("期望 %q，实际 %q", expected, acc.String())
    }
}