Update the fly machines autostop flag

This flag now accepts the new string values for autostop ("off", "stop",
"suspend") in addition to the original boolean ones.

internal/command/machine/run.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"fmt"
 	"math/rand"
+	"strconv"
 	"strings"
 	"time"
 
@@ -112,10 +113,10 @@ var sharedFlags = flag.Set{
 		Description: "Automatically start a stopped Machine when a network request is received",
 		Default:     true,
 	},
-	flag.Bool{
+	flag.String{
 		Name:        "autostop",
 		Description: "Automatically stop a Machine when there are no network requests for it",
-		Default:     true,
+		NoOptDefVal: "true",
 	},
 	flag.String{
 		Name: "restart",
@@ -774,10 +775,22 @@ func determineMachineConfig(
 		}
 
 		if flag.IsSpecified(ctx, "autostop") {
-			if flag.GetBool(ctx, "autostop") {
-				s.Autostop = fly.Pointer(fly.MachineAutostopStop)
+			// We'll try to parse it as a boolean first for backward
+			// compatibility. (strconv.ParseBool is what the pflag
+			// library uses for booleans under the hood.)
+			asString := flag.GetString(ctx, "autostop")
+			if asBool, err := strconv.ParseBool(asString); err == nil {
+				if asBool {
+					s.Autostop = fly.Pointer(fly.MachineAutostopStop)
+				} else {
+					s.Autostop = fly.Pointer(fly.MachineAutostopOff)
+				}
 			} else {
-				s.Autostop = fly.Pointer(fly.MachineAutostopOff)
+				var value fly.MachineAutostop
+				if err := value.UnmarshalText([]byte(asString)); err != nil {
+					return nil, err
+				}
+				s.Autostop = fly.Pointer(value)
 			}
 		}
 

internal/flag/flag.go

@@ -92,6 +92,7 @@ type String struct {
 	Shorthand    string
 	Description  string
 	Default      string
+	NoOptDefVal  string
 	ConfName     string
 	EnvName      string
 	Hidden       bool
@@ -110,6 +111,9 @@ func (s String) addTo(cmd *cobra.Command) {
 
 	f := flags.Lookup(s.Name)
 	f.Hidden = s.Hidden
+	if s.NoOptDefVal != "" {
+		f.NoOptDefVal = s.NoOptDefVal
+	}
 
 	// Aliases
 	for _, name := range s.Aliases {