From ebd915043e2b09ce4314137faf961126816fb70b Mon Sep 17 00:00:00 2001
From: AndrewMcBurney <andrewrobertmcburney@gmail.com>
Date: Thu, 8 Feb 2018 13:27:23 -0500
Subject: [PATCH 1/2] Use infinite sized queue in rack test context to avoid
 deadlock situation when data is never consumed from the
 Action::Dispatch::Response::Buffer.

---
 actionpack/lib/action_controller/metal/live.rb | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/actionpack/lib/action_controller/metal/live.rb b/actionpack/lib/action_controller/metal/live.rb
index 2f4c8fb83cd07..6c4c09438b879 100644
--- a/actionpack/lib/action_controller/metal/live.rb
+++ b/actionpack/lib/action_controller/metal/live.rb
@@ -141,7 +141,21 @@ def initialize(response)
         @cv = new_cond
         @aborted = false
         @ignore_disconnect = false
-        super(response, SizedQueue.new(10))
+
+        # https://github.com/rails/rails/issues/31813:
+        #
+        # In a browser context, the browser consumes data as soon as it's
+        # generated, freeing up space in the SizedQueue. However, in a rack
+        # test context, this is not the case, as data is never consumed. This
+        # leads to a deadlock upon trying to insert the 11th element in the
+        # queue, since the queue is waiting for space to become available
+        # before inserting the element:
+        #
+        #   http://ruby-doc.org/stdlib-2.0.0/libdoc/thread/rdoc/SizedQueue.html#method-i-push
+        #
+        # Thus, use an infinite sized Queue in rack test contexts to work around
+        # the issue where data is never consumed from the queue.
+        super(response, Rails.env.test? ? Queue.new : SizedQueue.new(10))
       end
 
       def write(string)

From cfd64d8079eb00a6fb4451cb7674bd927c3c91e1 Mon Sep 17 00:00:00 2001
From: AndrewMcBurney <andrewrobertmcburney@gmail.com>
Date: Fri, 9 Feb 2018 09:52:36 -0500
Subject: [PATCH 2/2] Updated test coupled to queue length in
 `actionpack/test/controller/live_stream_test.rb`, and removed superfluous
 comment in `actionpack/lib/action_controller/metal/live.rb`.

---
 .../lib/action_controller/metal/live.rb       | 14 -------
 .../test/controller/live_stream_test.rb       | 40 ++++++++++---------
 2 files changed, 21 insertions(+), 33 deletions(-)

diff --git a/actionpack/lib/action_controller/metal/live.rb b/actionpack/lib/action_controller/metal/live.rb
index 6c4c09438b879..6d89b9d49abc7 100644
--- a/actionpack/lib/action_controller/metal/live.rb
+++ b/actionpack/lib/action_controller/metal/live.rb
@@ -141,20 +141,6 @@ def initialize(response)
         @cv = new_cond
         @aborted = false
         @ignore_disconnect = false
-
-        # https://github.com/rails/rails/issues/31813:
-        #
-        # In a browser context, the browser consumes data as soon as it's
-        # generated, freeing up space in the SizedQueue. However, in a rack
-        # test context, this is not the case, as data is never consumed. This
-        # leads to a deadlock upon trying to insert the 11th element in the
-        # queue, since the queue is waiting for space to become available
-        # before inserting the element:
-        #
-        #   http://ruby-doc.org/stdlib-2.0.0/libdoc/thread/rdoc/SizedQueue.html#method-i-push
-        #
-        # Thus, use an infinite sized Queue in rack test contexts to work around
-        # the issue where data is never consumed from the queue.
         super(response, Rails.env.test? ? Queue.new : SizedQueue.new(10))
       end
 
diff --git a/actionpack/test/controller/live_stream_test.rb b/actionpack/test/controller/live_stream_test.rb
index 431fe90b23a24..6811fd3a36393 100644
--- a/actionpack/test/controller/live_stream_test.rb
+++ b/actionpack/test/controller/live_stream_test.rb
@@ -330,25 +330,27 @@ def test_async_stream
     end
 
     def test_abort_with_full_buffer
-      @controller.latch = Concurrent::CountDownLatch.new
-      @controller.error_latch = Concurrent::CountDownLatch.new
-
-      capture_log_output do |output|
-        get :overfill_buffer_and_die, format: "plain"
-
-        t = Thread.new(response) { |resp|
-          resp.await_commit
-          _, _, body = resp.to_a
-          body.each do
-            @controller.latch.wait
-            body.close
-            break
-          end
-        }
-
-        t.join
-        @controller.error_latch.wait
-        assert_match "Error while streaming", output.rewind && output.read
+      Rails.stub(:env, ActiveSupport::StringInquirer.new("production")) do
+        @controller.latch = Concurrent::CountDownLatch.new
+        @controller.error_latch = Concurrent::CountDownLatch.new
+
+        capture_log_output do |output|
+          get :overfill_buffer_and_die, format: "plain"
+
+          t = Thread.new(response) { |resp|
+            resp.await_commit
+            _, _, body = resp.to_a
+            body.each do
+              @controller.latch.wait
+              body.close
+              break
+            end
+          }
+
+          t.join
+          @controller.error_latch.wait
+          assert_match "Error while streaming", output.rewind && output.read
+        end
       end
     end