feat(cobra): add cobra bind support

bind.go

@@ -99,6 +99,7 @@ import (
 	"strings"
 	"time"
 
+	"github.com/spf13/cobra"
 	"github.com/spf13/pflag"
 )
 
@@ -289,6 +290,19 @@ func Bind(fs FlagSet, v interface{}, opts ...Option) error {
 	return newBind(opts...).bind(fs, v)
 }
 
+func BindCobra(cmd *cobra.Command, v interface{}, opts ...Option) (err error) {
+	if err = newBind(append(opts, CobraFilter("persistent"))...).bind(cmd.PersistentFlags(), v); err != nil {
+		return err
+	}
+	if err = newBind(append(opts, CobraFilter("local"))...).bind(cmd.LocalFlags(), v); err != nil {
+		return err
+	}
+	if err = newBind(append(opts, CobraFilter("flags"))...).bind(cmd.Flags(), v); err != nil {
+		return err
+	}
+	return nil
+}
+
 func (b bind) bind(fs FlagSet, v interface{}) (err error) {
 
 	// Hand control over to the Binder implementation.
@@ -353,7 +367,7 @@ func (b bind) bind(fs FlagSet, v interface{}) (err error) {
 		tagStr, hasTag := structField.Tag.Lookup("flag")
 		tag := newFlagTag(tagStr)
 
-		if tag.IsIgnored {
+		if b.IsIgnored(tag) {
 			continue
 		}
 
@@ -590,6 +604,7 @@ func bindPFlag(fs PFlagSet, tag flagTag, p interface{}, typeName string) bool {
 			// If not, use the pflagValue shim...
 			pp = pflagValue{p, typeName}
 		}
+
 		f = fs.VarPF(pp, tag.Name, tag.ShortName, tag.Usage)
 	case *json.RawMessage:
 		f = fs.VarPF((*JSONRawMessage)(p), tag.Name, tag.ShortName, tag.Usage)

bind_test.go

@@ -33,6 +33,7 @@ import (
 	"testing"
 	"time"
 
+	"github.com/spf13/cobra"
 	"github.com/spf13/pflag"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
@@ -112,7 +113,7 @@ func (test *BindTest) test(t *testing.T) {
 	for _, use := range test.UsageContains {
 		assert.Contains(usage, use, "flag.FlagSet.Usage()")
 	}
-	//fmt.Println(usage)
+	// fmt.Println(usage)
 	if test.UsePFlag {
 		for _, use := range test.UsageNotContains {
 			assert.NotContains(usage, use, "flag.FlagSet.Usage()")
@@ -239,6 +240,56 @@ func TestBind(t *testing.T) {
 	}
 }
 
+type ValidCobraFlagConfig struct {
+	StringVar string `flag:"string-var,s;default value;my usage;persistent;"`
+}
+
+func TestBindCobra(t *testing.T) {
+	tt := []struct {
+		name      string
+		F         interface{}
+		FName     string
+		FCobraSet string
+		FWant     interface{}
+		Err       error
+	}{
+		{
+			name:      "with persistent flags",
+			F:         &ValidCobraFlagConfig{},
+			FName:     "string-var",
+			FCobraSet: "persistent",
+			FWant:     "default value",
+			Err:       nil,
+		},
+	}
+
+	for _, tt := range tt {
+		t.Run(tt.name, func(t *testing.T) {
+			cmd := &cobra.Command{}
+			err := BindCobra(cmd, tt.F)
+			if tt.Err != nil {
+				assert.Equal(t, tt.Err, err)
+			}
+
+			var fs *pflag.FlagSet
+			switch tt.FCobraSet {
+			case "persistent":
+				fs = cmd.PersistentFlags()
+			case "local":
+				fs = cmd.LocalFlags()
+			case "flags":
+				fs = cmd.Flags()
+			default:
+				panic("unsupported cobra FlagSet")
+			}
+
+			got := fs.Lookup(tt.FName)
+			assert.NotNil(t, got)
+			assert.Equal(t, fmt.Sprintf("%v", tt.FWant), got.Value.String())
+		})
+	}
+}
+
 var tests = []BindTest{
 	{
 		Name:    "ErrorInvalidType_bool",

flagtag.go

@@ -50,6 +50,11 @@ type flagTag struct {
 
 	// Nested struct
 	Flatten bool // `flag:";;;flatten"`
+
+	// Nested struct
+	Persistent bool // `flag:";;;persistent"`
+	Local      bool // `flag:";;;local"`
+	Flags      bool // `flag:";;;flags"`
 }
 
 // newFlagTag parses all possible tag settings.
@@ -115,5 +120,14 @@ func (fTag *flagTag) parseOptions(opts string) {
 	opts = strings.ToLower(opts)
 	fTag.Hidden = strings.Contains(opts, "hidden")
 	fTag.HideDefault = strings.Contains(opts, "hide-default")
-	fTag.Flatten = strings.Contains(opts, "flatten")
+	switch {
+	case strings.Contains(opts, "persistent"):
+		fTag.Persistent = true
+	case strings.Contains(opts, "local"):
+		fTag.Local = true
+	case strings.Contains(opts, "flags"):
+		fallthrough
+	default:
+		fTag.Flags = true
+	}
 }

go.mod

@@ -3,6 +3,7 @@ module github.com/AdamSLevy/flagbind
 go 1.14
 
 require (
+	github.com/spf13/cobra v1.3.0
 	github.com/spf13/pflag v1.0.5
-	github.com/stretchr/testify v1.5.1
+	github.com/stretchr/testify v1.7.0
 )