fix: command.Names should not contain an empty string when command ha…

…s no name or no alias

command.go

@@ -92,14 +92,12 @@ func (c *Command) FullName() string {
 
 func (c *Command) PreferredName() string {
 	name := c.FullName()
-	if len(c.Names()) > 1 {
-		// first alias is what we prefer
-		name = c.Names()[1]
-	}
 	if name == "" && len(c.Aliases) > 0 {
 		names := []string{}
 		for _, a := range c.Aliases {
-			names = append(names, a.String())
+			if name := a.String(); name != "" {
+				names = append(names, a.String())
+			}
 		}
 		return strings.Join(names, ", ")
 	}
@@ -170,12 +168,19 @@ func (c *Command) Names() []string {
 	if c.Category != "" {
 		name = c.Category + ":" + name
 	}
-	names := []string{name}
+	names := []string{}
+	if name != "" {
+		names = append(names, name)
+	}
 	for _, a := range c.Aliases {
-		if !a.Hidden {
+		if a.Hidden {
+			continue
+		}
+		if name := a.String(); name != "" {
 			names = append(names, a.String())
 		}
 	}
+
 	return names
 }
 

command_test.go

@@ -23,6 +23,7 @@ import (
 	"errors"
 	"flag"
 	"io"
+	"reflect"
 	"strings"
 	"testing"
 
@@ -146,3 +147,23 @@ func TestFuzzyCommandNames(t *testing.T) {
 		t.Fatalf("expected no matches, got %v", c)
 	}
 }
+
+func TestCommandWithNoNames(t *testing.T) {
+	c := Command{
+		Aliases: []*Alias{
+			{},
+			{Name: "foo"},
+			{Name: "bar"},
+		},
+	}
+
+	if got, expected := c.Names(), []string{"foo", "bar"}; len(got) != 2 {
+		t.Fatalf("expected two names, got %v", len(got))
+	} else if !reflect.DeepEqual(got, expected) {
+		t.Fatalf("expected %v, got %v", expected, got)
+	}
+
+	if name := c.PreferredName(); name != "foo, bar" {
+		t.Fatalf(`expected "foo, bar", got "%v"`, name)
+	}
+}