JMS #14: Moving toward having and app object

app.go

@@ -0,0 +1,48 @@
+package cli
+
+import (
+	"os"
+)
+
+type App struct {
+	// The name of the program. Defaults to os.Args[0]
+	Name string
+	// Description of the program.
+	Usage string
+	// Version of the program
+	Version string
+	// List of commands to execute
+	Commands []Command
+	Flags    []Flag
+	// The action to execute when no subcommands are specified
+	Action Handler
+}
+
+func NewApp() *App {
+	return &App{
+		Name:    os.Args[0],
+		Usage:   "A new cli application",
+		Version: "0.0.0",
+		Action:  ShowHelp,
+	}
+}
+
+func (a *App) Run(arguments []string) {
+	set := flagSet(a.Flags)
+	set.Parse(arguments[1:])
+
+	context := NewContext(a, set, set)
+	args := context.Args()
+	if len(args) > 0 {
+		name := args[0]
+		for _, c := range append(a.Commands, HelpCommand) {
+			if c.HasName(name) {
+				c.Run(context)
+				return
+			}
+		}
+	}
+
+	// Run default Action
+	a.Action(context)
+}

cli.go

@@ -1,43 +1,3 @@
 package cli
 
-import "os"
-
-// The name of the program. Defaults to os.Args[0]
-var Name = os.Args[0]
-
-// Description of the program.
-var Usage = "<No Description>"
-
-// Version of the program
-var Version = "0.0.0"
-
-// List of commands to execute
-var Commands []Command
-
-var Flags []Flag
-
-// The action to execute when no subcommands are specified
-var Action = ShowHelp
-
-func Run(arguments []string) {
-
-	set := flagSet(Flags)
-	set.Parse(arguments[1:])
-
-	context := NewContext(set, set)
-	args := context.Args()
-	if len(args) > 0 {
-		name := args[0]
-		for _, c := range append(Commands, HelpCommand) {
-			if c.HasName(name) {
-				c.Run(context)
-				return
-			}
-		}
-	}
-
-	// Run default Action
-	Action(context)
-}
-
 type Handler func(context *Context)

cli_test.go

@@ -6,38 +6,41 @@ import (
 )
 
 func Test_SettingFlags(t *testing.T) {
-	Flags = []Flag{
+	app := NewApp()
+	app.Flags = []Flag{
 		StringFlag{"foo", "default", "a string flag"},
 		IntFlag{"bar", 42, "an int flag"},
 		BoolFlag{"bat", "a bool flag"},
 	}
-	Action = func(c *Context) {
+	app.Action = func(c *Context) {
 		expect(t, c.String("foo"), "hello world")
 		expect(t, c.Int("bar"), 245)
 		expect(t, c.Bool("bat"), true)
 	}
-	Run([]string{"command", "--foo", "hello world", "--bar", "245", "--bat"})
+	app.Run([]string{"command", "--foo", "hello world", "--bar", "245", "--bat"})
 }
 
 func Test_FlagDefaults(t *testing.T) {
-	Flags = []Flag{
+	app := NewApp()
+	app.Flags = []Flag{
 		StringFlag{"foo", "default", "a string flag"},
 		IntFlag{"bar", 42, "an int flag"},
 		BoolFlag{"bat", "a bool flag"},
 	}
-	Action = func(c *Context) {
+	app.Action = func(c *Context) {
 		expect(t, c.String("foo"), "default")
 		expect(t, c.Int("bar"), 42)
 		expect(t, c.Bool("bat"), false)
 	}
-	Run([]string{"command"})
+	app.Run([]string{"command"})
 }
 
 func TestCommands(t *testing.T) {
-	Flags = []Flag{
+	app := NewApp()
+	app.Flags = []Flag{
 		StringFlag{"name", "jeremy", "a name to print"},
 	}
-	Commands = []Command{
+	app.Commands = []Command{
 		{
 			Name: "print",
 			Flags: []Flag{
@@ -49,10 +52,10 @@ func TestCommands(t *testing.T) {
 			},
 		},
 	}
-	Action = func(c *Context) {
+	app.Action = func(c *Context) {
 		t.Error("default action should not be called")
 	}
-	Run([]string{"command", "--name", "jordie", "print", "--age", "21"})
+	app.Run([]string{"command", "--name", "jordie", "print", "--age", "21"})
 }
 
 /* Test Helpers */

command.go

@@ -12,7 +12,7 @@ type Command struct {
 func (command Command) Run(c *Context) {
 	set := flagSet(command.Flags)
 	set.Parse(c.Args()[1:])
-	command.Action(NewContext(set, c.globalSet))
+	command.Action(NewContext(c.App, set, c.globalSet))
 }
 
 func (command Command) HasName(name string) bool {

context.go

@@ -10,12 +10,13 @@ import (
 // can be used to retrieve context-specific Args and
 // parsed command-line options.
 type Context struct {
+	App       *App
 	flagSet   *flag.FlagSet
 	globalSet *flag.FlagSet
 }
 
-func NewContext(set *flag.FlagSet, globalSet *flag.FlagSet) *Context {
+func NewContext(app *App, set *flag.FlagSet, globalSet *flag.FlagSet) *Context {
-	return &Context{set, globalSet}
+	return &Context{app, set, globalSet}
 }
 
 // Looks up the value of a local int flag, returns 0 if no int flag exists

context_test.go

@@ -10,7 +10,7 @@ func Test_New(t *testing.T) {
 	set.Int("myflag", 12, "doc")
 	globalSet := flag.NewFlagSet("test", 0)
 	globalSet.Int("myflag", 42, "doc")
-	c := NewContext(set, globalSet)
+	c := NewContext(nil, set, globalSet)
 	expect(t, c.Int("myflag"), 12)
 	expect(t, c.GlobalInt("myflag"), 42)
 }
@@ -18,28 +18,28 @@ func Test_New(t *testing.T) {
 func Test_Int(t *testing.T) {
 	set := flag.NewFlagSet("test", 0)
 	set.Int("myflag", 12, "doc")
-	c := NewContext(set, set)
+	c := NewContext(nil, set, set)
 	expect(t, c.Int("myflag"), 12)
 }
 
 func Test_String(t *testing.T) {
 	set := flag.NewFlagSet("test", 0)
 	set.String("myflag", "hello world", "doc")
-	c := NewContext(set, set)
+	c := NewContext(nil, set, set)
 	expect(t, c.String("myflag"), "hello world")
 }
 
 func Test_Bool(t *testing.T) {
 	set := flag.NewFlagSet("test", 0)
 	set.Bool("myflag", false, "doc")
-	c := NewContext(set, set)
+	c := NewContext(nil, set, set)
 	expect(t, c.Bool("myflag"), false)
 }
 
 func Test_Args(t *testing.T) {
 	set := flag.NewFlagSet("test", 0)
 	set.Bool("myflag", false, "doc")
-	c := NewContext(set, set)
+	c := NewContext(nil, set, set)
 	set.Parse([]string{"--myflag", "bat", "baz"})
 	expect(t, len(c.Args()), 2)
 	expect(t, c.Bool("myflag"), true)

flag.go

@@ -9,7 +9,7 @@ type Flag interface {
 }
 
 func flagSet(flags []Flag) *flag.FlagSet {
-	set := flag.NewFlagSet(Name, flag.ExitOnError)
+	set := flag.NewFlagSet("cli", flag.ExitOnError)
 	for _, f := range flags {
 		f.Apply(set)
 	}

help.go

@@ -4,14 +4,6 @@ import "os"
 import "text/tabwriter"
 import "text/template"
 
-type HelpData struct {
-	Name     string
-	Usage    string
-	Version  string
-	Commands []Command
-	Flags    []Flag
-}
-
 var HelpCommand = Command{
 	Name:      "help",
 	ShortName: "h",
@@ -39,16 +31,9 @@ GLOBAL OPTIONS
     {{range .Flags}}{{.}}
     {{end}}
 `
-	data := HelpData{
-		Name,
-		Usage,
-		Version,
-		append(Commands, HelpCommand),
-		Flags,
-	}
 
 	w := tabwriter.NewWriter(os.Stdout, 0, 8, 1, '\t', 0)
 	t := template.Must(template.New("help").Parse(helpTemplate))
-	t.Execute(w, data)
+	t.Execute(w, c.App)
 	w.Flush()
 }