From bed89eb683e6016be7247041db3c998e57fc838c Mon Sep 17 00:00:00 2001
From: Hugo Hromic <hhromic@gmail.com>
Date: Thu, 18 Jan 2024 23:04:55 +0000
Subject: [PATCH] Implement scanning of version flag in specs for usage
 generation

---
 usage.go | 20 +++++++++++++++++++-
 1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/usage.go b/usage.go
index ae98478..4a056f3 100644
--- a/usage.go
+++ b/usage.go
@@ -48,18 +48,36 @@ func (p *Parser) WriteUsageForSubcommand(w io.Writer, subcommand ...string) erro
 	}
 
 	var positionals, longOptions, shortOptions []*spec
+	var hasVersionOption bool
 	for _, spec := range cmd.specs {
 		switch {
 		case spec.positional:
 			positionals = append(positionals, spec)
 		case spec.long != "":
 			longOptions = append(longOptions, spec)
+			if spec.long == "version" {
+				hasVersionOption = true
+			}
 		case spec.short != "":
 			shortOptions = append(shortOptions, spec)
 		}
 	}
 
-	if p.version != "" {
+	// make a list of ancestor commands so that we print with full context
+	// also determine if any ancestor has a version option spec
+	var ancestors []string
+	ancestor := cmd
+	for ancestor != nil {
+		for _, spec := range ancestor.specs {
+			if spec.long == "version" {
+				hasVersionOption = true
+			}
+		}
+		ancestors = append(ancestors, ancestor.name)
+		ancestor = ancestor.parent
+	}
+
+	if !hasVersionOption && p.version != "" {
 		fmt.Fprintln(w, p.version)
 	}