Update help output

Author: Faris Huskovic

command_test.go

@@ -14,18 +14,23 @@ const (
 
 	expectedParentCmdHelpOutput = `Usage: mockParentCmd Mock parent command usage.
 
-Mock parent command description.
+Description: Mock parent command description.
 
 Commands:
-	s,sc,sub,mockSubCmd  - A simple mock subcommand with aliases.
+	s, sc, sub, mockSubCmd  - A simple mock subcommand with aliases and its own subcommand.
 `
 )
 
 var subCmd = &mockSubCmd{buf: new(bytes.Buffer)}
 
 type (
+	// Mock for root/parent command.
 	mockParentCmd struct{}
-	mockSubCmd    struct{ buf *bytes.Buffer }
+	// Mock subcommand with aliases and a nested
+	// sucommand of its own.
+	mockSubCmd struct{ buf *bytes.Buffer }
+	// Mock subcommand with aliases and no nested subcommands.
+	mockSubCmdNoNested struct{}
 )
 
 func (c *mockParentCmd) Run(fl *pflag.FlagSet) {}
@@ -47,14 +52,29 @@ func (c *mockSubCmd) Run(fl *pflag.FlagSet) {
 	}
 }
 
+func (c *mockSubCmd) Subcommands() []Command {
+	return []Command{new(mockSubCmd)}
+}
+
 func (c *mockSubCmd) Write(b []byte) (int, error) { return c.buf.Write(b) }
 
 func (c *mockSubCmd) Spec() CommandSpec {
 	return CommandSpec{
 		Name:    "mockSubCmd",
 		Usage:   "Test a subcommand.",
 		Aliases: []string{"s", "sc", "sub"},
-		Desc:    "A simple mock subcommand with aliases.",
+		Desc:    "A simple mock subcommand with aliases and its own subcommand.",
+	}
+}
+
+func (c *mockSubCmdNoNested) Run(fl *pflag.FlagSet) {}
+
+func (c *mockSubCmdNoNested) Spec() CommandSpec {
+	return CommandSpec{
+		Name:    "mockSubCmdNoNested",
+		Usage:   "Used for help output tests.",
+		Aliases: []string{"s", "sc", "sub"},
+		Desc:    "A simple mock subcommand with aliases and no nested subcommands.",
 	}
 }
 
@@ -103,3 +123,49 @@ func TestSubcmdAliasesInParentCmdHelpOutput(t *testing.T) {
 	expected := expectedParentCmdHelpOutput
 	assert.Equal(t, "display_subcmd_aliases_in_parentcmd_help_output", expected, got)
 }
+
+func TestSubCmdHelpOutput(t *testing.T) {
+	withNested := `Usage: mockSubCmd Test a subcommand.
+
+Aliases: s, sc, sub
+
+Description: A simple mock subcommand with aliases and its own subcommand.
+
+Commands:
+	s, sc, sub, mockSubCmd  - A simple mock subcommand with aliases and its own subcommand.
+`
+
+	noNested := `Usage: mockSubCmdNoNested Used for help output tests.
+
+Aliases: s, sc, sub
+
+Description: A simple mock subcommand with aliases and no nested subcommands.
+`
+
+	for _, test := range []struct {
+		cmd            Command
+		name, expected string
+	}{
+		{
+			name:     "subcmd w/nested subcmd.",
+			expected: withNested,
+			cmd:      new(mockSubCmd),
+		},
+		{
+			name:     "subcmd w/no nested subcmds.",
+			expected: noNested,
+			cmd:      new(mockSubCmdNoNested),
+		},
+	} {
+		t.Run(test.name, func(t *testing.T) {
+			buf := new(bytes.Buffer)
+			name := test.cmd.Spec().Name
+			fl := pflag.NewFlagSet(name, pflag.ExitOnError)
+			// If the help output is not written to the buffer
+			// in the format we expect then the test will fail.
+			renderHelp(name, test.cmd, fl, buf)
+			got := string(buf.Bytes())
+			assert.Equal(t, t.Name(), test.expected, got)
+		})
+	}
+}

help.go

@@ -52,10 +52,10 @@ func renderHelp(fullName string, cmd Command, fl *pflag.FlagSet, w io.Writer) {
 
 	// If the command has aliases, add them to the output as a comma-separated list.
 	if spec.HasAliases() {
-		fmt.Fprintf(&b, "Aliases: %v", spec.Aliases)
+		fmt.Fprintf(&b, "Aliases: %s\n\n", strings.Join(spec.Aliases, ", "))
 	}
 	// Render usage and description.
-	usageAndDesc := fmt.Sprintf("%s%s\n", b.String(), spec.Desc)
+	usageAndDesc := fmt.Sprintf("%sDescription: %s\n", b.String(), spec.Desc)
 	fmt.Fprint(w, usageAndDesc)
 
 	tw := tabwriter.NewWriter(w, 0, 4, 2, ' ', tabwriter.StripEscape)
@@ -80,7 +80,7 @@ func renderHelp(fullName string, cmd Command, fl *pflag.FlagSet, w io.Writer) {
 				continue
 			}
 
-			allNames := strings.Join(append(spec.Aliases, spec.Name), ",")
+			allNames := strings.Join(append(spec.Aliases, spec.Name), ", ")
 
 			fmt.Fprintf(tw,
 				tabEscape+"\t"+tabEscape+"%v\t- %v\n",