Golang "testing" file:line prefix

desired_test.go

package main

import (
	"fmt"
	"path/filepath"
	"runtime"
	"testing"
)

func flushTestConnections() {}
func closeTestConnections() {}

func die(t *testing.T, v ...interface{}) {
	flushTestConnections()
	closeTestConnections()
	t.LogLine(false)
	defer t.LogLine(true)
	_, file, ln, _ := runtime.Caller(1)
	t.Fatalf("%s:%d: %s", filepath.Base(file), ln, fmt.Sprint(v...))
}

func TestDie(t *testing.T) { die(t, "now the line number makes sense") }

issue_test.go

package main

import "testing"

func flushTestConnections() {}
func closeTestConnections() {}

func die(t *testing.T, v ...interface{}) {
	flushTestConnections()
	closeTestConnections()
	t.Fatal(v...)
}

func TestDie(t *testing.T) { die(t, "line number doesn't make sense") }