plan 10: commands refuse global flags they do not use

1 files changed, 24 insertions, 0 deletions

diff --git a/cmd/krino/common.go b/cmd/krino/common.go
index 15c32f6..5b6869a 100644
--- a/cmd/krino/common.go
+++ b/cmd/krino/common.go
@@ -33,6 +33,30 @@ func minAgeOverride(g *globals) (d time.Duration, set bool, err error) {
 	return d, true, nil
 }
 
+// refuseUnusedFlags refuses the global flags a command does not use -
+// -y and -n unless usesYesDry, and --json and -v - instead of silently
+// ignoring them, so "krino -n new ...", meant as a preview, cannot write
+// config (re-review cli F4). It reports whether it refused.
+func refuseUnusedFlags(g *globals, stderr io.Writer, cmd string, usesYesDry bool) (int, bool) {
+	var given []string
+	if !usesYesDry && g.yes {
+		given = append(given, "-y")
+	}
+	if !usesYesDry && g.dry {
+		given = append(given, "-n")
+	}
+	if g.json {
+		given = append(given, "--json")
+	}
+	if g.verbose {
+		given = append(given, "-v")
+	}
+	if len(given) == 0 {
+		return 0, false
+	}
+	return usageError(stderr, fmt.Sprintf("%s does not take %s", cmd, strings.Join(given, ", "))), true
+}
+
 // cacheDir is where every directory's keyword cache lives (spec §6.1).
 func cacheDir() string {
 	return filepath.Join(xdg.CacheHome(), "krino")