better hint for windows shells

Signed-off-by: Evan Hazlett <ejhazlett@gmail.com>

commands/commands.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"os"
 	"path/filepath"
+	"runtime"
 	"sort"
 	"strings"
 
@@ -658,8 +659,8 @@ func detectShell() (string, error) {
 	// attempt to get the SHELL env var
 	shell := filepath.Base(os.Getenv("SHELL"))
 	// none detected; check for windows env
-	if shell == "." && os.Getenv("windir") != "" {
-		log.Printf("On Windows, please specify either cmd or powershell with the --shell flag.\n\n")
+	if runtime.GOOS == "windows" {
+		log.Printf("On Windows, please specify either 'cmd' or 'powershell' with the --shell flag.\n\n")
 		return "", ErrUnknownShell
 	}
 

commands/create.go

@@ -2,7 +2,6 @@ package commands
 
 import (
 	"fmt"
-	"os"
 	"path/filepath"
 
 	log "github.com/Sirupsen/logrus"
@@ -89,21 +88,8 @@ func cmdCreate(c *cli.Context) {
 		log.Fatalf("error setting active host: %v", err)
 	}
 
-	info := ""
-	userShell := filepath.Base(os.Getenv("SHELL"))
-
-	switch userShell {
-	case "fish":
-		info = fmt.Sprintf("%s env %s | source", c.App.Name, name)
-	default:
-		info = fmt.Sprintf(`eval "$(%s env %s)"`, c.App.Name, name)
-	}
-
-	log.Infof("%q has been created and is now the active machine.", name)
-
-	if info != "" {
-		log.Infof("To point your Docker client at it, run this in your shell: %s", info)
-	}
+	info := fmt.Sprintf("%s env %s", c.App.Name, name)
+	log.Infof("To point your Docker client at it, run this in your shell: %s", info)
 }
 
 // If the user has specified a driver, they should not see the flags for all