From 7c973a26c7bd6ecd8d86bb435d93ff98df2710fa Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Mart=C3=AD?= <mvdan@mvdan.cc>
Date: Tue, 1 Oct 2024 16:55:09 +0200
Subject: [PATCH] cmd/xurls: reject unexpected -fix string values

While here, tweak the help text and run -fix itself on the README.
---
 README.md         | 4 ++--
 cmd/xurls/main.go | 5 ++++-
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/README.md b/README.md
index 51560f3..298c3e0 100644
--- a/README.md
+++ b/README.md
@@ -18,8 +18,8 @@ func main() {
 }
 ```
 
-Since API is centered around [regexp.Regexp](https://golang.org/pkg/regexp/#Regexp),
-many other methods are available, such as finding the [byte indexes](https://golang.org/pkg/regexp/#Regexp.FindAllIndex)
+Since API is centered around [regexp.Regexp](https://pkg.go.dev/regexp#Regexp),
+many other methods are available, such as finding the [byte indexes](https://pkg.go.dev/regexp#Regexp.FindAllIndex)
 for all matches.
 
 The regular expressions are compiled when the API is first called.
diff --git a/cmd/xurls/main.go b/cmd/xurls/main.go
index 201aaa7..3a56281 100644
--- a/cmd/xurls/main.go
+++ b/cmd/xurls/main.go
@@ -47,7 +47,7 @@ func init() {
 	flag.Var(&fix, "fix", "")
 	flag.Usage = func() {
 		fmt.Fprint(os.Stderr, `
-Usage: xurls [-h] [files]
+Usage: xurls [flags] [files]
 
 xurls extracts urls from text using regular expressions.
 If no files are given, it reads from standard input.
@@ -230,6 +230,9 @@ func main1() int {
 	case "auto", "all": // enabled via -fix=auto, -fix=all, etc
 	case "true": // enabled via -fix; normalize
 		fix = "auto"
+	default:
+		flag.Usage()
+		return 1
 	}
 	var re *regexp.Regexp
 	if *relaxed {