JMS #4: Support for global flags in cli.Context

cli.go

@@ -24,7 +24,7 @@ func Run(args []string) {
 	set := flagSet(Flags)
 	set.Parse(args[1:])
 
-	context := NewContext(set)
+	context := NewContext(set, set)
 	if len(args) > 1 {
 		name := args[1]
 		for _, c := range append(Commands, HelpCommand) {

context.go

@@ -10,48 +10,79 @@ import (
 // can be used to retrieve context-specific Args and
 // parsed command-line options.
 type Context struct {
-	flagSet *flag.FlagSet
+	flagSet   *flag.FlagSet
+	globalSet *flag.FlagSet
 }
 
-func NewContext(flagSet *flag.FlagSet) *Context {
-	return &Context{flagSet}
+func NewContext(set *flag.FlagSet, globalSet *flag.FlagSet) *Context {
+	return &Context{set, globalSet}
 }
 
+// Looks up the value of a local int flag, returns 0 if no int flag exists
 func (c *Context) Int(name string) int {
-	flag := c.flagSet.Lookup(name)
-	if flag != nil {
-		val, err := strconv.Atoi(flag.Value.String())
-		if err != nil {
-			panic(err)
-		}
-		return val
-	} else {
-		return 0
-	}
+	return c.lookupInt(name, c.flagSet)
 }
 
+// Looks up the value of a local bool flag, returns false if no bool flag exists
 func (c *Context) Bool(name string) bool {
-	flag := c.flagSet.Lookup(name)
-	if flag != nil {
-		val, err := strconv.ParseBool(flag.Value.String())
+	return c.lookupBool(name, c.flagSet)
+}
+
+// Looks up the value of a local string flag, returns "" if no string flag exists
+func (c *Context) String(name string) string {
+	return c.lookupString(name, c.flagSet)
+}
+
+// Looks up the value of a global int flag, returns 0 if no int flag exists
+func (c *Context) GlobalInt(name string) int {
+	return c.lookupInt(name, c.globalSet)
+}
+
+// Looks up the value of a global bool flag, returns false if no bool flag exists
+func (c *Context) GlobalBool(name string) bool {
+	return c.lookupBool(name, c.globalSet)
+}
+
+// Looks up the value of a global string flag, returns "" if no string flag exists
+func (c *Context) GlobalString(name string) string {
+	return c.lookupString(name, c.globalSet)
+}
+
+func (c *Context) Args() []string {
+	return c.flagSet.Args()
+}
+
+func (c *Context) lookupInt(name string, set *flag.FlagSet) int {
+	f := set.Lookup(name)
+	if f != nil {
+		val, err := strconv.Atoi(f.Value.String())
 		if err != nil {
-			panic(err)
+			return 0
 		}
 		return val
 	} else {
-		return false
+		return 0
 	}
 }
 
-func (c *Context) String(name string) string {
-	flag := c.flagSet.Lookup(name)
-	if flag != nil {
-		return flag.Value.String()
+func (c *Context) lookupString(name string, set *flag.FlagSet) string {
+	f := set.Lookup(name)
+	if f != nil {
+		return f.Value.String()
 	} else {
 		return ""
 	}
 }
 
-func (c *Context) Args() []string {
-	return c.flagSet.Args()
+func (c *Context) lookupBool(name string, set *flag.FlagSet) bool {
+	f := set.Lookup(name)
+	if f != nil {
+		val, err := strconv.ParseBool(f.Value.String())
+		if err != nil {
+			return false
+		}
+		return val
+	} else {
+		return false
+	}
 }

context_test.go

@@ -5,31 +5,41 @@ import (
 	"testing"
 )
 
+func Test_New(t *testing.T) {
+	set := flag.NewFlagSet("test", 0)
+	set.Int("myflag", 12, "doc")
+	globalSet := flag.NewFlagSet("test", 0)
+	globalSet.Int("myflag", 42, "doc")
+	c := NewContext(set, globalSet)
+	expect(t, c.Int("myflag"), 12)
+	expect(t, c.GlobalInt("myflag"), 42)
+}
+
 func Test_Int(t *testing.T) {
 	set := flag.NewFlagSet("test", 0)
 	set.Int("myflag", 12, "doc")
-	c := NewContext(set)
+	c := NewContext(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)
+	c := NewContext(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)
+	c := NewContext(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)
+	c := NewContext(set, set)
 	set.Parse([]string{"--myflag", "bat", "baz"})
 	expect(t, len(c.Args()), 2)
 	expect(t, c.Bool("myflag"), true)