From 631c27ad471085c26fbb8c2ce441ed1feb36526d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E7=8E=8B=E8=83=9C?= <2318857637@qq.com>
Date: Thu, 11 Jun 2026 10:53:50 +0800
Subject: [PATCH] fix: let returns override returnsArg
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Signed-off-by: 王胜 <2318857637@qq.com>
---
 src/sinon/default-behaviors.js | 1 +
 test/src/stub-test.js          | 9 +++++++++
 2 files changed, 10 insertions(+)

diff --git a/src/sinon/default-behaviors.js b/src/sinon/default-behaviors.js
index df5a00a76..82368b667 100644
--- a/src/sinon/default-behaviors.js
+++ b/src/sinon/default-behaviors.js
@@ -145,6 +145,7 @@ const defaultBehaviors = {
     returns: function returns(fake, value) {
         fake.callsThrough = false;
         fake.returnValue = value;
+        fake.returnArgAt = undefined;
         fake.resolve = false;
         fake.reject = false;
         fake.returnValueDefined = true;
diff --git a/test/src/stub-test.js b/test/src/stub-test.js
index adc016925..157026f44 100644
--- a/test/src/stub-test.js
+++ b/test/src/stub-test.js
@@ -721,6 +721,15 @@ describe("stub", function () {
             assert.equals(obj.fn("myarg"), "myarg");
         });
 
+        it("is superseded by returns", function () {
+            const stub = createStub();
+
+            stub.returnsArg(0);
+            stub.returns(42);
+
+            assert.equals(stub("myarg"), 42);
+        });
+
         it("throws if no index is specified", function () {
             const stub = createStub();