spec: fix broken transactions from preventing error reporting

this is only necessary in test, when we have the fixture transaction

also adjust our detection of "real" transaction in test

Change-Id: I81960f62f9656d709face95cf1288c397d0f5773
Reviewed-on: https://gerrit.instructure.com/72161
Tested-by: Jenkins
Reviewed-by: Simon Williams <simon@instructure.com>
Product-Review: Cody Cutrer <cody@instructure.com>
QA-Review: Cody Cutrer <cody@instructure.com>

config/initializers/active_record.rb

@@ -699,7 +699,8 @@ ActiveRecord::Relation.class_eval do
     (connection.adapter_name == 'PostgreSQL' &&
       (Shackles.environment == :slave ||
         connection.readonly? ||
-        connection.open_transactions > (Rails.env.test? ? 1 : 0)))
+        (!Rails.env.test? && connection.open_transactions > 0) ||
+        in_transaction_in_test?))
   end
 
   def find_in_batches_with_cursor(options = {})
@@ -737,7 +738,7 @@ ActiveRecord::Relation.class_eval do
     # changing the name (and source location) of this method
     transaction_regex = /^#{Regexp.escape(transaction_method)}:\d+:in `transaction/.freeze
     # transactions due to spec fixtures are _not_in the callstack, so we only need to find 1
-    !!caller.find { |s| s =~ transaction_regex }
+    !!caller.find { |s| s =~ transaction_regex && !s.include?('spec_helper.rb') }
   end
 
   def find_in_batches_with_temp_table(options = {})

spec/spec_helper.rb

@@ -55,6 +55,36 @@ Dir[Rails.root.join("spec/support/**/*.rb")].each { |f| require f }
 
 ActionView::TestCase::TestController.view_paths = ApplicationController.view_paths
 
+# this makes sure that a broken transaction becomes functional again
+# by the time we hit rescue_action_in_public, so that the error report
+# can be recorded
+ActionController::Base.set_callback(:process_action, :around, ->(_r, block) do
+  exception = nil
+  ActiveRecord::Base.transaction(joinable: false, requires_new: true) do
+    begin
+      if Rails.version < '5'
+        # that transaction didn't count as a "real" transaction within the test
+        test_open_transactions = ActiveRecord::Base.connection.instance_variable_get(:@test_open_transactions)
+        ActiveRecord::Base.connection.instance_variable_set(:@test_open_transactions, test_open_transactions.to_i - 1)
+        begin
+          block.call
+        ensure
+          ActiveRecord::Base.connection.instance_variable_set(:@test_open_transactions, test_open_transactions)
+        end
+      else
+        block.call
+      end
+    rescue ActiveRecord::StatementInvalid
+      # these need to properly roll back the transaction
+      raise
+    rescue
+      # anything else, the transaction needs to commit, but we need to re-raise outside the transaction
+      exception = $!
+    end
+  end
+  raise exception if exception
+end)
+
 module RSpec::Core::Hooks
 class AfterContextHook < Hook
   def run(example)