Render flag help to tabwriter

ammario · ammario · commit d3a506bdbe1c · 2019-07-26T11:36:04.000-05:00
diff --git a/help.go b/help.go
@@ -33,6 +33,9 @@ func fmtDefValue(value interface{}) string {
 	}
 }
 
+// \xFF is used to escape a \t so tabwriter ignores it.
+const tabEscape = "\xFF"
+
 func renderFlagHelp(fl *flag.FlagSet, w io.Writer) {
 	var count int
 	fl.VisitAll(func(f *flag.Flag) {
@@ -42,9 +45,9 @@ func renderFlagHelp(fl *flag.FlagSet, w io.Writer) {
 
 		count++
 		if f.DefValue == "" {
-			fmt.Fprintf(w, "\t%v%v\t%v\n", flagDashes(f.Name), f.Name, f.Usage)
+			fmt.Fprintf(w, tabEscape+"\t%v%v\t%v\n", flagDashes(f.Name), f.Name, f.Usage)
 		} else {
-			fmt.Fprintf(w, "\t%v%v=%v\t%v\n", flagDashes(f.Name), f.Name, fmtDefValue(f.DefValue), f.Usage)
+			fmt.Fprintf(w, tabEscape+"\t%v%v=%v\t%v\n", flagDashes(f.Name), f.Name, fmtDefValue(f.DefValue), f.Usage)
 		}
 	})
 }
@@ -57,8 +60,11 @@ func renderHelp(cmd Command, fl *flag.FlagSet, w io.Writer) {
 	)
 	fmt.Fprintf(w, "%v\n", cmd.Spec().Desc)
 
+	tw := tabwriter.NewWriter(w, 0, 4, 2, ' ', tabwriter.StripEscape)
+	defer tw.Flush()
+
 	// Render flag help.
-	renderFlagHelp(fl, w)
+	renderFlagHelp(fl, tw)
 
 	// Render subcommand summaries.
 	pc, ok := cmd.(ParentCommand)
@@ -69,20 +75,16 @@ func renderHelp(cmd Command, fl *flag.FlagSet, w io.Writer) {
 			fmt.Fprint(w, "Commands:\n")
 		}
 
-		tw := tabwriter.NewWriter(w, 0, 0, 2, ' ', tabwriter.StripEscape)
 		for _, cmd := range pc.Subcommands() {
 			if cmd.Spec().Hidden {
 				continue
 			}
 
-			// \xFF is used to escape the leading \t so tabwriter ignores it
 			fmt.Fprintf(tw,
-				"\xFF\t\xFF%v\t%v\n",
+				tabEscape+"\t"+tabEscape+"%v\t%v\n",
 				cmd.Spec().Name,
 				cmd.Spec().ShortDesc(),
 			)
 		}
-
-		tw.Flush()
 	}
 }

Original file line number	Diff line number	Diff line change
`@@ -33,6 +33,9 @@ func fmtDefValue(value interface{}) string {`
`33`	`33`	`}`
`34`	`34`	`}`
`35`	`35`
	`36`	`+// \xFF is used to escape a \t so tabwriter ignores it.`
	`37`	`+const tabEscape = "\xFF"`
	`38`	`+`
`36`	`39`	`func renderFlagHelp(fl *flag.FlagSet, w io.Writer) {`
`37`	`40`	`var count int`
`38`	`41`	`fl.VisitAll(func(f *flag.Flag) {`
`@@ -42,9 +45,9 @@ func renderFlagHelp(fl *flag.FlagSet, w io.Writer) {`
`42`	`45`
`43`	`46`	`count++`
`44`	`47`	`if f.DefValue == "" {`
`45`		`- fmt.Fprintf(w, "\t%v%v\t%v\n", flagDashes(f.Name), f.Name, f.Usage)`
	`48`	`+ fmt.Fprintf(w, tabEscape+"\t%v%v\t%v\n", flagDashes(f.Name), f.Name, f.Usage)`
`46`	`49`	`} else {`
`47`		`- fmt.Fprintf(w, "\t%v%v=%v\t%v\n", flagDashes(f.Name), f.Name, fmtDefValue(f.DefValue), f.Usage)`
	`50`	`+ fmt.Fprintf(w, tabEscape+"\t%v%v=%v\t%v\n", flagDashes(f.Name), f.Name, fmtDefValue(f.DefValue), f.Usage)`
`48`	`51`	`}`
`49`	`52`	`})`
`50`	`53`	`}`
`@@ -57,8 +60,11 @@ func renderHelp(cmd Command, fl *flag.FlagSet, w io.Writer) {`
`57`	`60`	`)`
`58`	`61`	`fmt.Fprintf(w, "%v\n", cmd.Spec().Desc)`
`59`	`62`
	`63`	`+ tw := tabwriter.NewWriter(w, 0, 4, 2, ' ', tabwriter.StripEscape)`
	`64`	`+ defer tw.Flush()`
	`65`	`+`
`60`	`66`	`// Render flag help.`
`61`		`- renderFlagHelp(fl, w)`
	`67`	`+ renderFlagHelp(fl, tw)`
`62`	`68`
`63`	`69`	`// Render subcommand summaries.`
`64`	`70`	`pc, ok := cmd.(ParentCommand)`
`@@ -69,20 +75,16 @@ func renderHelp(cmd Command, fl *flag.FlagSet, w io.Writer) {`
`69`	`75`	`fmt.Fprint(w, "Commands:\n")`
`70`	`76`	`}`
`71`	`77`
`72`		`- tw := tabwriter.NewWriter(w, 0, 0, 2, ' ', tabwriter.StripEscape)`
`73`	`78`	`for _, cmd := range pc.Subcommands() {`
`74`	`79`	`if cmd.Spec().Hidden {`
`75`	`80`	`continue`
`76`	`81`	`}`
`77`	`82`
`78`		`- // \xFF is used to escape the leading \t so tabwriter ignores it`
`79`	`83`	`fmt.Fprintf(tw,`
`80`		`- "\xFF\t\xFF%v\t%v\n",`
	`84`	`+ tabEscape+"\t"+tabEscape+"%v\t%v\n",`
`81`	`85`	`cmd.Spec().Name,`
`82`	`86`	`cmd.Spec().ShortDesc(),`
`83`	`87`	`)`
`84`	`88`	`}`
`85`		`-`
`86`		`- tw.Flush()`
`87`	`89`	`}`
`88`	`90`	`}`