Golang Go语言中导包为什么会失败？

文件结构

/home/vagrant/gocode/gtail
├── go.mod
├── go.sum
├── log_watcher.go
├── main.go
└── playbooks
    ├── file_watcher
    │   └── compile.json
    └── session.yaml

log_watcher 的内容

package log_watcher
import (
“fmt”
“log”
“os”
“path/filepath”
)
type LogWatcher struct {
Pattern string
}
func (c *LogWatcher) tail() {
matches, err := filepath.Glob(c.Pattern)
if err != nil {
log.Fatal(err)
return
}
for k, v := range matches {
file_obj, err := os.Open(v)
if err != nil {
log.Fatal(err)
return
}
go func() {
buf := make([]byte, 1024)
for {
n, _ := file_obj.Read(buf)
if 0 == n {
break
}
fmt.Print(buf[:n])
}
}()
}
return
}

main.go 的内容

package main
import (
“fmt”
“log”
“os”
"github.com/urfave/cli"
"gtail/log_watcher"
)
func main() {
var pattern string
app := &cli.App{
Name:  “gtail”,
Usage: “golang tail”,
Flags: []cli.Flag{
&cli.StringFlag{
Name:        “pattern”,
Usage:       “language for the greeting”,
Required:    true,
Destination: &pattern,
},
},
Action: func(c *cli.Context) error {
if len(pattern) == 0 {
fmt.Printf(“miss pattern\n”)
return nil
}
		var log_watcher = &LogWatcher{
			Pattern: pattern,
		}
		log_watcher.tail()

	},
}

err := app.Run(os.Args)
if err != nil {
	log.Fatal(err)
}
}

为什么 build 的时候提示

can't load package: package gtail: found packages log_watcher (log_watcher.go) and main (main.go) in /home/vagrant/gocode/gtail

我另一个项目这么导包又成功了,感觉 golang 的导包真的玄学,