🐛 bug: Fix cookie secure flag with SameSite None

ctx.go

@@ -425,6 +425,10 @@ func (c *DefaultCtx) Cookie(cookie *Cookie) {
 		cookie.Path = "/"
 	}
 
+	if utils.ToLower(cookie.SameSite) == CookieSameSiteNoneMode && !cookie.Secure {
+		cookie.Secure = true
+	}
+
 	if cookie.SessionOnly {
 		cookie.MaxAge = 0
 		cookie.Expires = time.Time{}

ctx_test.go

@@ -1112,6 +1112,49 @@
 	require.Equal(t, "ps=v; path=/; secure; SameSite=None; Partitioned", c.Res().Get(HeaderSetCookie))
 }
 
+// go test -run Test_Ctx_Cookie_SameSiteNoneAutoSecure
+func Test_Ctx_Cookie_SameSiteNoneAutoSecure(t *testing.T) {
+	app := New()
+	c := app.AcquireCtx(&fasthttp.RequestCtx{})
+	t.Cleanup(func() {
+		app.ReleaseCtx(c)
+	})
+
+	testCases := []struct {
+		description string
+		sameSite	string
+	}{
+		{
+			description: "samesite is 'none'",
+			sameSite:    CookieSameSiteNoneMode,
+		},
+		{
+			description: "samesite is 'None'",
+			sameSite:    "None",
+		},
+		{
+			description: "samesite is 'NONE'",
+			sameSite:    "NONE",
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.description, func(t *testing.T) {
+			// Reset response header for each sub-test to ensure a clean state
+			c.Response().Header.Reset()
+
+			ck := &Cookie{
+				Name:     "auto",
+				Value:    "v",
+				SameSite: tc.sameSite,
+			}
+			c.Res().Cookie(ck)
+
+			require.Equal(t, "auto=v; path=/; secure; SameSite=None", c.Res().Get(HeaderSetCookie))
+		})
+	}
+}
+
 // go test -run Test_Ctx_Cookie_Invalid
 func Test_Ctx_Cookie_Invalid(t *testing.T) {
 	t.Parallel()