modified: cmd/immortal/main.go

	modified:   parser.go
	modified:   parser_test.go
	deleted:    user.go

cmd/immortal/main.go

@@ -12,9 +12,7 @@ import (
 var version string
 
 func main() {
-	parser := &immortal.Parse{
-		UserFinder: &immortal.User{},
-	}
+	parser := new(immortal.Parse)
 
 	// flag set
 	fs := flag.NewFlagSet(os.Args[0], flag.ExitOnError)

parser.go

@@ -4,17 +4,16 @@ import (
 	"flag"
 	"fmt"
 	"os"
+	"os/user"
 )
 
 type Parser interface {
 	Parse(fs *flag.FlagSet) (*Flags, error)
 	exists(path string) bool
-	UserFinder
 }
 
 type Parse struct {
 	Flags
-	UserFinder
 }
 
 func (self *Parse) Parse(fs *flag.FlagSet) (*Flags, error) {
@@ -87,9 +86,13 @@ func ParseArgs(p Parser, fs *flag.FlagSet) (*Flags, error) {
 
 	// if -u
 	if flags.User != "" {
-		usr, err := p.Lookup(flags.User)
+		usr, err := user.Lookup(flags.User)
 		if err != nil {
-			return nil, err
+			if _, ok := err.(user.UnknownUserError); ok {
+				return nil, fmt.Errorf("User %q does not exist.", flags.User)
+			} else if err != nil {
+				return nil, fmt.Errorf("Error looking up user: %q", flags.User)
+			}
 		}
 		flags.user = usr
 	}

parser_test.go

@@ -196,14 +196,12 @@ func TestParseArgsTable(t *testing.T) {
 		{[]string{"cmd", "-P", "/path/to/parent"}, true},
 		{[]string{"cmd", "-u", "root"}, true},
 		{[]string{"cmd", "-u", "root", "cmd"}, false},
-		{[]string{"cmd", "-u", "toornonexistent", "cmd"}, true},
+		{[]string{"cmd", "-u", "toor-nonexistent", "cmd"}, true},
 	}
 	var helpCalled = false
 	for _, f := range flagTest {
 		os.Args = f.flag
-		parser := &Parse{
-			UserFinder: &User{},
-		}
+		parser := new(Parse)
 		fs := flag.NewFlagSet("TestParseArgsTable", flag.ContinueOnError)
 		fs.Usage = func() { helpCalled = true }
 		_, err := ParseArgs(parser, fs)