From 1720d3e11cd8be727a535aa09be2284f3a4019d3 Mon Sep 17 00:00:00 2001
From: albertony <12441419+albertony@users.noreply.github.com>
Date: Fri, 3 Nov 2023 23:35:48 +0100
Subject: [PATCH] help: global flags help command extended filtering

---
 cmd/help.go              | 18 +++++++++++++-----
 fs/config/flags/flags.go | 17 +++++++++--------
 2 files changed, 22 insertions(+), 13 deletions(-)

diff --git a/cmd/help.go b/cmd/help.go
index ee01b7840..e6106d2f7 100644
--- a/cmd/help.go
+++ b/cmd/help.go
@@ -59,20 +59,25 @@ var helpCommand = &cobra.Command{
 }
 
 // to filter the flags with
-var flagsRe *regexp.Regexp
+var (
+	filterFlagsGroup     string
+	filterFlagsRe        *regexp.Regexp
+	filterFlagsNamesOnly bool
+)
 
 // Show the flags
 var helpFlags = &cobra.Command{
 	Use:   "flags [<filter>]",
 	Short: "Show the global flags for rclone",
 	Run: func(command *cobra.Command, args []string) {
+		command.Flags()
 		if len(args) > 0 {
 			re, err := filter.GlobStringToRegexp(args[0], false)
 			if err != nil {
-				log.Fatalf("Failed to compile flags regexp: %v", err)
+				log.Fatalf("Invalid flag filter: %v", err)
 			}
-			fs.Debugf(nil, "Flags filter: %s", re.String())
-			flagsRe = re
+			fs.Debugf(nil, "Flag filter: %s", re.String())
+			filterFlagsRe = re
 		}
 		if GeneratingDocs {
 			Root.SetUsageTemplate(docFlagsTemplate)
@@ -159,7 +164,7 @@ func setupRootCommand(rootCmd *cobra.Command) {
 				fs.Errorf(nil, "Flag --%s is unknown", flag.Name)
 			}
 		})
-		groups := flags.All.Filter(flagsRe).Include(cmd.Annotations["groups"])
+		groups := flags.All.Filter(filterFlagsGroup, filterFlagsRe, filterFlagsNamesOnly).Include(cmd.Annotations["groups"])
 		return groups.Groups
 	})
 	rootCmd.SetUsageTemplate(usageTemplate)
@@ -171,6 +176,9 @@ func setupRootCommand(rootCmd *cobra.Command) {
 
 	rootCmd.AddCommand(helpCommand)
 	helpCommand.AddCommand(helpFlags)
+	helpFlagsFlags := helpFlags.Flags()
+	flags.StringVarP(helpFlagsFlags, &filterFlagsGroup, "group", "", "", "Only include flags from specific group", "")
+	flags.BoolVarP(helpFlagsFlags, &filterFlagsNamesOnly, "name", "", false, "Apply filter only on flag names", "")
 	helpCommand.AddCommand(helpBackends)
 	helpCommand.AddCommand(helpBackend)
 
diff --git a/fs/config/flags/flags.go b/fs/config/flags/flags.go
index 25183fa0f..10b1fd77f 100644
--- a/fs/config/flags/flags.go
+++ b/fs/config/flags/flags.go
@@ -50,16 +50,17 @@ func (gs *Groups) NewGroup(name, help string) *Group {
 }
 
 // Filter makes a copy of groups filtered by flagsRe
-func (gs *Groups) Filter(flagsRe *regexp.Regexp) *Groups {
+func (gs *Groups) Filter(group string, filterRe *regexp.Regexp, filterNamesOnly bool) *Groups {
 	newGs := NewGroups()
 	for _, g := range gs.Groups {
-		newG := newGs.NewGroup(g.Name, g.Help)
-		g.Flags.VisitAll(func(f *pflag.Flag) {
-			matched := flagsRe == nil || flagsRe.MatchString(f.Name) || flagsRe.MatchString(f.Usage)
-			if matched {
-				newG.Flags.AddFlag(f)
-			}
-		})
+		if group == "" || strings.EqualFold(g.Name, group) {
+			newG := newGs.NewGroup(g.Name, g.Help)
+			g.Flags.VisitAll(func(f *pflag.Flag) {
+				if filterRe == nil || filterRe.MatchString(f.Name) || (!filterNamesOnly && filterRe.MatchString(f.Usage)) {
+					newG.Flags.AddFlag(f)
+				}
+			})
+		}
 	}
 	return newGs
 }