show only subcommand flags with bash completion (#1186)

help.go

@@ -163,19 +163,26 @@ func DefaultCompleteWithFlags(cmd *Command) func(c *Context) {
 	return func(c *Context) {
 		if len(os.Args) > 2 {
 			lastArg := os.Args[len(os.Args)-2]
+
 			if strings.HasPrefix(lastArg, "-") {
-				printFlagSuggestions(lastArg, c.App.Flags, c.App.Writer)
 				if cmd != nil {
 					printFlagSuggestions(lastArg, cmd.Flags, c.App.Writer)
+
+					return
 				}
+
+				printFlagSuggestions(lastArg, c.App.Flags, c.App.Writer)
+
 				return
 			}
 		}
+
 		if cmd != nil {
 			printCommandSuggestions(cmd.Subcommands, c.App.Writer)
-		} else {
-			printCommandSuggestions(c.App.Commands, c.App.Writer)
+			return
 		}
+
+		printCommandSuggestions(c.App.Commands, c.App.Writer)
 	}
 }
 

help_test.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"io"
 	"io/ioutil"
+	"os"
 	"runtime"
 	"strings"
 	"testing"
@@ -1037,3 +1038,85 @@ func TestHideHelpCommand_WithSubcommands(t *testing.T) {
 		t.Errorf("Run returned unexpected error: %v", err)
 	}
 }
+
+func TestDefaultCompleteWithFlags(t *testing.T) {
+	origArgv := os.Args
+
+	t.Cleanup(func() {
+		os.Args = origArgv
+	})
+
+	for _, tc := range []struct {
+		name     string
+		c        *Context
+		cmd      *Command
+		argv     []string
+		expected string
+	}{
+		{
+			name:     "empty",
+			c:        &Context{App: &App{}},
+			cmd:      &Command{},
+			argv:     []string{"prog", "cmd"},
+			expected: "",
+		},
+		{
+			name: "typical-flag-suggestion",
+			c: &Context{App: &App{
+				Name: "cmd",
+				Flags: []Flag{
+					&BoolFlag{Name: "happiness"},
+					&Int64Flag{Name: "everybody-jump-on"},
+				},
+				Commands: []*Command{
+					{Name: "putz"},
+				},
+			}},
+			cmd: &Command{
+				Flags: []Flag{
+					&BoolFlag{Name: "excitement"},
+					&StringFlag{Name: "hat-shape"},
+				},
+			},
+			argv:     []string{"cmd", "--e", "--generate-bash-completion"},
+			expected: "--excitement\n",
+		},
+		{
+			name: "typical-command-suggestion",
+			c: &Context{App: &App{
+				Name: "cmd",
+				Flags: []Flag{
+					&BoolFlag{Name: "happiness"},
+					&Int64Flag{Name: "everybody-jump-on"},
+				},
+			}},
+			cmd: &Command{
+				Name: "putz",
+				Subcommands: []*Command{
+					{Name: "futz"},
+				},
+				Flags: []Flag{
+					&BoolFlag{Name: "excitement"},
+					&StringFlag{Name: "hat-shape"},
+				},
+			},
+			argv:     []string{"cmd", "--generate-bash-completion"},
+			expected: "futz\n",
+		},
+	} {
+		t.Run(tc.name, func(ct *testing.T) {
+			writer := &bytes.Buffer{}
+			tc.c.App.Writer = writer
+
+			os.Args = tc.argv
+			f := DefaultCompleteWithFlags(tc.cmd)
+			f(tc.c)
+
+			written := writer.String()
+
+			if written != tc.expected {
+				ct.Errorf("written help does not match expected %q != %q", written, tc.expected)
+			}
+		})
+	}
+}