为什么当我运行`go test`时该函数未定义？

Question

Here is the code

a.go

package main

import "fmt"

func Haha() {
    fmt.Println("in Haha")
}

func main() {
}

a_test.go

package main_test

import "testing"

func TestA(t *testing.T) {
    Haha()
}

go build works. But when I run ~/gopath/src/zjk/misc$ go test -v. Here is what I get

# zjk/misc_test
./a_test.go:6: undefined: Haha
FAIL    zjk/misc [build failed]

Answer 1

because you have different packages

should be:

a.go

package main

import "fmt"

func Haha() {
    fmt.Println("in Haha")
}

func main() {
}

a_test.go

package main

import "testing"

func TestA(t *testing.T) {
    Haha()
}

output:

# zjk/misc_test
in Haha
PASS
ok      github.com/qwertmax/so  0.009s