Return original response in debug middleware patch

lib/raven/integrations/rails/middleware/debug_exceptions_catcher.rb

@@ -3,9 +3,11 @@ class Rails
     module Middleware
       module DebugExceptionsCatcher
         def render_exception(env_or_request, exception)
-          env = env_or_request.respond_to?(:env) ? env_or_request.env : env_or_request
-          Raven::Rack.capture_exception(exception, env)
-        ensure
+          begin
+            env = env_or_request.respond_to?(:env) ? env_or_request.env : env_or_request
+            Raven::Rack.capture_exception(exception, env)
+          rescue # rubocop:disable Lint/HandleExceptions
+          end
           super
         end
       end
@@ -16,9 +18,11 @@ def self.included(base)
         end
 
         def render_exception_with_raven(env_or_request, exception)
-          env = env_or_request.respond_to?(:env) ? env_or_request.env : env_or_request
-          Raven::Rack.capture_exception(exception, env)
-        ensure
+          begin
+            env = env_or_request.respond_to?(:env) ? env_or_request.env : env_or_request
+            Raven::Rack.capture_exception(exception, env)
+          rescue # rubocop:disable Lint/HandleExceptions
+          end
           render_exception_without_raven(env_or_request, exception)
         end
       end

spec/raven/integrations/rails/middleware/debug_exceptions_catcher_spec.rb

@@ -0,0 +1,73 @@
+require 'spec_helper'
+require 'raven/integrations/rails/middleware/debug_exceptions_catcher'
+
+describe Raven::Rails::Middleware::DebugExceptionsCatcher do
+  let(:middleware) do
+    Class.new do
+      def initialize(app)
+        @app = app
+      end
+
+      def call(env)
+        @app.call(env)
+      rescue => e
+        render_exception(env, e)
+      end
+
+      def render_exception(_, exception)
+        [500, exception.message, {}]
+      end
+    end
+  end
+
+  let(:app) do
+    lambda { |_| raise "app error" } # rubocop:disable Style/Lambda
+  end
+
+  let(:env) { {} }
+
+  context "using include" do
+    before do
+      middleware.send(:include, Raven::Rails::Middleware::OldDebugExceptionsCatcher)
+    end
+
+    it "shows the exception" do
+      expect(middleware.new(app).call(env)).to eq([500, "app error", {}])
+    end
+
+    it "captures the exception" do
+      expect(Raven::Rack).to receive(:capture_exception)
+      middleware.new(app).call(env)
+    end
+
+    context "when an error is raised" do
+      it "shows the original exception" do
+        allow(Raven::Rack).to receive(:capture_exception).and_raise("raven error")
+        expect(middleware.new(app).call(env)).to eq([500, "app error", {}])
+      end
+    end
+  end
+
+  context "using prepend" do
+    before do
+      skip "prepend not available" unless middleware.respond_to?(:prepend, true)
+      middleware.send(:prepend, Raven::Rails::Middleware::DebugExceptionsCatcher)
+    end
+
+    it "shows the exception" do
+      expect(middleware.new(app).call(env)).to eq([500, "app error", {}])
+    end
+
+    it "captures the exception" do
+      expect(Raven::Rack).to receive(:capture_exception)
+      middleware.new(app).call(env)
+    end
+
+    context "when an error is raised" do
+      it "shows the original exception" do
+        allow(Raven::Rack).to receive(:capture_exception).and_raise("raven error")
+        expect(middleware.new(app).call(env)).to eq([500, "app error", {}])
+      end
+    end
+  end
+end