cli/pkg/cmd/alias/expand/expand.go
2021-08-25 12:41:30 +02:00

93 lines
2 KiB
Go

package expand
import (
"errors"
"fmt"
"os/exec"
"regexp"
"runtime"
"strings"
"github.com/cli/cli/v2/internal/config"
"github.com/cli/cli/v2/pkg/findsh"
"github.com/google/shlex"
)
// ExpandAlias processes argv to see if it should be rewritten according to a user's aliases. The
// second return value indicates whether the alias should be executed in a new shell process instead
// of running gh itself.
func ExpandAlias(cfg config.Config, args []string, findShFunc func() (string, error)) (expanded []string, isShell bool, err error) {
if len(args) < 2 {
// the command is lacking a subcommand
return
}
expanded = args[1:]
aliases, err := cfg.Aliases()
if err != nil {
return
}
expansion, ok := aliases.Get(args[1])
if !ok {
return
}
if strings.HasPrefix(expansion, "!") {
isShell = true
if findShFunc == nil {
findShFunc = findSh
}
shPath, shErr := findShFunc()
if shErr != nil {
err = shErr
return
}
expanded = []string{shPath, "-c", expansion[1:]}
if len(args[2:]) > 0 {
expanded = append(expanded, "--")
expanded = append(expanded, args[2:]...)
}
return
}
extraArgs := []string{}
for i, a := range args[2:] {
if !strings.Contains(expansion, "$") {
extraArgs = append(extraArgs, a)
} else {
expansion = strings.ReplaceAll(expansion, fmt.Sprintf("$%d", i+1), a)
}
}
lingeringRE := regexp.MustCompile(`\$\d`)
if lingeringRE.MatchString(expansion) {
err = fmt.Errorf("not enough arguments for alias: %s", expansion)
return
}
var newArgs []string
newArgs, err = shlex.Split(expansion)
if err != nil {
return
}
expanded = append(newArgs, extraArgs...)
return
}
func findSh() (string, error) {
shPath, err := findsh.Find()
if err != nil {
if errors.Is(err, exec.ErrNotFound) {
if runtime.GOOS == "windows" {
return "", errors.New("unable to locate sh to execute the shell alias with. The sh.exe interpreter is typically distributed with Git for Windows.")
}
return "", errors.New("unable to locate sh to execute shell alias with")
}
return "", err
}
return shPath, nil
}