fix(ifdata): Add flags to manpage

Author: gabe565

cmd/ifdata/usage.go

@@ -52,3 +52,15 @@ func usageFunc(cmd *cobra.Command) error {
 	cmd.SetUsageFunc(nil)
 	return cmd.Usage()
 }
+
+func ManOptions() string {
+	var s strings.Builder
+	for _, val := range formatterValues() {
+		if val == fmtNone {
+			continue
+		}
+
+		_, _ = fmt.Fprintf(&s, "\n.PP\n\\fB%s\\fP\n\t%s\n", val, val.description())
+	}
+	return s.String()
+}

internal/generate/manpages/main.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"bytes"
 	"compress/gzip"
 	"errors"
 	"io"
@@ -11,6 +12,7 @@ import (
 	"time"
 
 	"github.com/gabe565/moreutils/cmd"
+	"github.com/gabe565/moreutils/cmd/ifdata"
 	"github.com/gabe565/moreutils/internal/cmdutil"
 	"github.com/gabe565/moreutils/internal/cmdutil/subcommands"
 	"github.com/gabe565/moreutils/internal/generate/seealsoreplacer"
@@ -83,6 +85,14 @@ func main() {
 			w = seealsoreplacer.New(w, ".SH SEE ALSO\n", linked)
 		}
 
+		if subCmd.Name() == ifdata.Name {
+			w = optionsInserter{
+				w:      w,
+				find:   "help for " + ifdata.Name + "\n",
+				insert: ifdata.ManOptions(),
+			}
+		}
+
 		if err := doc.GenMan(subCmd, &header, w); err != nil {
 			panic(err)
 		}
@@ -97,3 +107,27 @@ func main() {
 		}
 	}
 }
+
+type optionsInserter struct {
+	w      io.Writer
+	find   string
+	insert string
+}
+
+func (o optionsInserter) Write(p []byte) (int, error) {
+	if !strings.HasSuffix(o.insert, "\n") {
+		o.insert += "\n"
+	}
+
+	if bytes.Contains(p, []byte(o.find)) {
+		beforeIdx := bytes.Index(p, []byte(o.find))
+		if beforeIdx == -1 {
+			panic("missing header: " + o.find)
+		}
+		beforeIdx += len(o.find)
+
+		_, err := o.w.Write(slices.Concat(p[:beforeIdx], []byte(o.find), []byte(o.insert), p[beforeIdx:]))
+		return len(p), err
+	}
+	return o.w.Write(p)
+}