From 3cdaafceebc69b9a2c8fc82108ef75a89cd260fc Mon Sep 17 00:00:00 2001
From: Wojtek Mach <wojtek@wojtekmach.pl>
Date: Fri, 28 Jun 2024 12:59:51 +0200
Subject: [PATCH] `redirect`: Cancel async request before redirecting

Closes #372
---
 lib/req/finch.ex        | 10 ++++++++++
 lib/req/steps.ex        |  4 ++++
 test/req/finch_test.exs | 23 +++++++++++++++++++++++
 3 files changed, 37 insertions(+)

diff --git a/lib/req/finch.ex b/lib/req/finch.ex
index c7fc07e..e870b0c 100644
--- a/lib/req/finch.ex
+++ b/lib/req/finch.ex
@@ -292,6 +292,16 @@ defmodule Req.Finch do
 
   defp finch_cancel(ref) do
     Finch.cancel_async_request(ref)
+    clean_responses(ref)
+    :ok
+  end
+
+  defp clean_responses(ref) do
+    receive do
+      {^ref, _} -> clean_responses(ref)
+    after
+      0 -> :ok
+    end
   end
 
   defp finch_name(request) do
diff --git a/lib/req/steps.ex b/lib/req/steps.ex
index a458183..be35e77 100644
--- a/lib/req/steps.ex
+++ b/lib/req/steps.ex
@@ -1691,6 +1691,10 @@ defmodule Req.Steps do
       redirect_count = Req.Request.get_private(request, :req_redirect_count, 0)
 
       if redirect_count < max_redirects do
+        with %Req.Response.Async{} <- response.body do
+          Req.cancel_async_response(response)
+        end
+
         request =
           request
           |> build_redirect_request(response, location)
diff --git a/test/req/finch_test.exs b/test/req/finch_test.exs
index 07c01f2..15d5822 100644
--- a/test/req/finch_test.exs
+++ b/test/req/finch_test.exs
@@ -401,6 +401,29 @@ defmodule Req.FinchTest do
       assert resp.status == 200
       assert :ok = Req.cancel_async_response(resp)
     end
+
+    @tag :capture_log
+    test "into: :self with redirect" do
+      %{url: url} =
+        TestHelper.start_http_server(fn conn ->
+          Plug.Conn.send_resp(conn, 200, "ok")
+        end)
+
+      %{url: url} =
+        TestHelper.start_http_server(fn conn ->
+          conn
+          |> Plug.Conn.put_resp_header("location", to_string(url))
+          |> Plug.Conn.send_resp(307, "redirecting to #{url}")
+        end)
+
+      req =
+        Req.new(
+          url: url,
+          into: :self
+        )
+
+      assert Req.get!(req).body |> Enum.to_list() == ["ok"]
+    end
   end
 
   describe "pool_options" do