为 golang 框架编写单元测试时应避免哪些常见错误？

func SomeFunc(input int) int {
  return input + 1
}

import "testing"

func TestSomeFunc(t *testing.T) {
  if got := SomeFunc(0); got != 1 {
    t.Errorf("SomeFunc(0) = %d, want 1", got)
  }
}

import "database/sql"

func GetUsers(db *sql.DB) []User {
  rows, err := db.Query("SELECT * FROM users")
  if err != nil {
    return nil
  }
  // ...

func GetUsers(repo UserRepository) []User {
  rows, err := repo.Query("SELECT * FROM users")
  if err != nil {
    return nil
  }
  // ...

import "net/http"

func GetXKCDComic(id int) (*http.Response, error) {
  req, err := http.NewRequest("GET", fmt.Sprintf("https://xkcd.com/%d/info.0.json", id), nil)
  if err != nil {
    return nil, err
  }
  // ...

func GetXKCDComic(repo XKCDRepository, id int) (*http.Response, error) {
  req, err := repo.NewRequest("GET", fmt.Sprintf("https://xkcd.com/%d/info.0.json", id), nil)
  if err != nil {
    return nil, err
  }
  // ...

func TestSomeFunc(t *testing.T) {
  if got := SomeFunc(-1); got > 0 {
    t.Error("SomeFunc(-1) should be negative")
  }
}

func TestSomeFunc(t *testing.T) {
  if got := SomeFunc(-1); got != -1 {
    t.Errorf("SomeFunc(-1) = %d, want -1", got)
  }
}