From ca47a6bca30b64750f102a3019c0e9fe92afc867 Mon Sep 17 00:00:00 2001
From: Matthias Keckl <53833818+matthyk@users.noreply.github.com>
Date: Mon, 12 Feb 2024 06:55:55 +0100
Subject: [PATCH] set `this` context for action callback (#59)

---
 index.d.ts                |  2 +-
 tests/arguments.test-d.ts | 10 ++++++++++
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index ee39351..4ae9a9e 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -691,7 +691,7 @@ export class CommanderError extends Error {
      *
      * @returns `this` command for chaining
      */
-    action(fn: (...args: [...Args, Opts, this]) => void | Promise<void>): this;
+    action(fn: (this: this, ...args: [...Args, Opts, this]) => void | Promise<void>): this;
 
     /**
      * Define option with `flags`, `description`, and optional argument parsing function or `defaultValue` or both.
diff --git a/tests/arguments.test-d.ts b/tests/arguments.test-d.ts
index 76d7aed..c9bdf12 100644
--- a/tests/arguments.test-d.ts
+++ b/tests/arguments.test-d.ts
@@ -314,6 +314,16 @@ program
     expectAssignable<OptionValues>(options);
   });
 
+// `this` should be current Command
+program
+  .option('-o, --opt')
+  .option('-v, --verbose')
+  .argument('<arg>')
+  .argument('<second argument>')
+  .action(function () {
+    expectType<Command<[string, string], { opt?: true, verbose?: true }>>(this)
+  })
+
 // default type ignored when arg is required
 expectType<('C')>(
   program