Merge pull request #154 from codegangsta/allow-writer-to-be-set

Allow writer to be set

help.go

@@ -1,11 +1,6 @@
 package cli
 
-import (
-	"fmt"
-	"os"
-	"text/tabwriter"
-	"text/template"
-)
+import "fmt"
 
 // The text template for the Default help topic.
 // cli.go uses text/template to render templates. You can
@@ -94,7 +89,9 @@ var helpSubcommand = Command{
 }
 
 // Prints help for the App
-var HelpPrinter = printHelp
+type helpPrinter func(templ string, data interface{})
+
+var HelpPrinter helpPrinter = nil
 
 // Prints version for the App
 var VersionPrinter = printVersion
@@ -106,9 +103,9 @@ func ShowAppHelp(c *Context) {
 // Prints the list of subcommands as the default app completion method
 func DefaultAppComplete(c *Context) {
 	for _, command := range c.App.Commands {
-		fmt.Println(command.Name)
+		fmt.Fprintln(c.App.Writer, command.Name)
 		if command.ShortName != "" {
-			fmt.Println(command.ShortName)
+			fmt.Fprintln(c.App.Writer, command.ShortName)
 		}
 	}
 }
@@ -125,7 +122,7 @@ func ShowCommandHelp(c *Context, command string) {
 	if c.App.CommandNotFound != nil {
 		c.App.CommandNotFound(c, command)
 	} else {
-		fmt.Printf("No help topic for '%v'\n", command)
+		fmt.Fprintf(c.App.Writer, "No help topic for '%v'\n", command)
 	}
 }
 
@@ -140,7 +137,7 @@ func ShowVersion(c *Context) {
 }
 
 func printVersion(c *Context) {
-	fmt.Printf("%v version %v\n", c.App.Name, c.App.Version)
+	fmt.Fprintf(c.App.Writer, "%v version %v\n", c.App.Name, c.App.Version)
 }
 
 // Prints the lists of commands within a given context
@@ -159,16 +156,6 @@ func ShowCommandCompletions(ctx *Context, command string) {
 	}
 }
 
-func printHelp(templ string, data interface{}) {
-	w := tabwriter.NewWriter(os.Stdout, 0, 8, 1, '\t', 0)
-	t := template.Must(template.New("help").Parse(templ))
-	err := t.Execute(w, data)
-	if err != nil {
-		panic(err)
-	}
-	w.Flush()
-}
-
 func checkVersion(c *Context) bool {
 	if c.GlobalBool("version") {
 		ShowVersion(c)