From ad8c121a84d5baa522054e7b84f2c24c4ecbdbe2 Mon Sep 17 00:00:00 2001
From: Wendell Sun <iwendellsun@gmail.com>
Date: Sun, 1 May 2022 00:24:13 +0800
Subject: [PATCH] Add ActionableFlag interface instead of modifying Flag
 interface directly

---
 app.go  | 6 ++++--
 flag.go | 7 ++++++-
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/app.go b/app.go
index 99f31a8532..7b217b5b0f 100644
--- a/app.go
+++ b/app.go
@@ -524,8 +524,10 @@ func runFlagActions(c *Context, fs []Flag) error {
 			}
 		}
 		if isSet {
-			if err := f.RunAction(c); err != nil {
-				return err
+			if af, ok := f.(ActionableFlag); ok {
+				if err := af.RunAction(c); err != nil {
+					return err
+				}
 			}
 		}
 	}
diff --git a/flag.go b/flag.go
index b8d49c9254..9aaed98315 100644
--- a/flag.go
+++ b/flag.go
@@ -84,6 +84,12 @@ func (f FlagsByName) Swap(i, j int) {
 	f[i], f[j] = f[j], f[i]
 }
 
+// ActionableFlag is an interface that wraps Flag interface and RunAction operation.
+type ActionableFlag interface {
+	Flag
+	RunAction(*Context) error
+}
+
 // Flag is a common interface related to parsing flags in cli.
 // For more advanced flag parsing techniques, it is recommended that
 // this interface be implemented.
@@ -93,7 +99,6 @@ type Flag interface {
 	Apply(*flag.FlagSet) error
 	Names() []string
 	IsSet() bool
-	RunAction(*Context) error
 }
 
 // RequiredFlag is an interface that allows us to mark flags as required