DEV: Upgrade Discourse to Rails 6 (#8083)

* Adjustments to pass specs on Rails 6.0.0
* Use classic autoloader instead of Zeitwerk
* Update Rails 6.0.0 deprecated methods
* Rails 6.0.0 not allowing column with integer name
* Drop freedom_patches/rails6.rb
* Default value for trigger_transactional_callbacks? is true
* Bump rspec-rails version to 4.0.0.beta2

lib/freedom_patches/rails6.rb

@@ -1,110 +0,0 @@
-# frozen_string_literal: true
-
-# this is a quick backport of a new method introduced in Rails 6
-# to be removed after we upgrade to Rails 6
-if ! defined? ActionView::Base.with_view_paths
-  class ActionView::Base
-    class << self
-      alias with_view_paths new
-    end
-  end
-end
-
-# backport of https://github.com/rails/rails/commit/890485cfce4c361c03a41ec23b0ba187007818cc
-if !defined? ActionDispatch::Http::ContentDisposition
-  module ActionDispatch
-    module Http
-      class ContentDisposition
-        def self.format(disposition:, filename:)
-          new(disposition: disposition, filename: filename).to_s
-        end
-
-        attr_reader :disposition, :filename
-
-        def initialize(disposition:, filename:)
-          @disposition = disposition
-          @filename = filename
-        end
-
-        TRADITIONAL_ESCAPED_CHAR = /[^ A-Za-z0-9!#$+.^_`|~-]/
-
-        def ascii_filename
-          'filename="' + percent_escape(I18n.transliterate(filename), TRADITIONAL_ESCAPED_CHAR) + '"'
-        end
-
-        RFC_5987_ESCAPED_CHAR = /[^A-Za-z0-9!#$&+.^_`|~-]/
-
-        def utf8_filename
-          "filename*=UTF-8''" + percent_escape(filename, RFC_5987_ESCAPED_CHAR)
-        end
-
-        def to_s
-          if filename
-            "#{disposition}; #{ascii_filename}; #{utf8_filename}"
-          else
-            "#{disposition}"
-          end
-        end
-
-        private
-        def percent_escape(string, pattern)
-          string.gsub(pattern) do |char|
-            char.bytes.map { |byte| "%%%02X" % byte }.join
-          end
-        end
-      end
-    end
-  end
-
-  module ActionController
-    module DataStreaming
-      private
-      def send_file_headers!(options)
-        type_provided = options.has_key?(:type)
-
-        content_type = options.fetch(:type, DEFAULT_SEND_FILE_TYPE)
-        self.content_type = content_type
-        response.sending_file = true
-
-        raise ArgumentError, ":type option required" if content_type.nil?
-
-        if content_type.is_a?(Symbol)
-          extension = Mime[content_type]
-          raise ArgumentError, "Unknown MIME type #{options[:type]}" unless extension
-          self.content_type = extension
-        else
-          if !type_provided && options[:filename]
-            # If type wasn't provided, try guessing from file extension.
-            content_type = Mime::Type.lookup_by_extension(File.extname(options[:filename]).downcase.delete(".")) || content_type
-          end
-          self.content_type = content_type
-        end
-
-        disposition = options.fetch(:disposition, DEFAULT_SEND_FILE_DISPOSITION)
-        if disposition
-          headers["Content-Disposition"] = ActionDispatch::Http::ContentDisposition.format(disposition: disposition, filename: options[:filename])
-        end
-
-        headers["Content-Transfer-Encoding"] = "binary"
-
-        # Fix a problem with IE 6.0 on opening downloaded files:
-        # If Cache-Control: no-cache is set (which Rails does by default),
-        # IE removes the file it just downloaded from its cache immediately
-        # after it displays the "open/save" dialog, which means that if you
-        # hit "open" the file isn't there anymore when the application that
-        # is called for handling the download is run, so let's workaround that
-        response.cache_control[:public] ||= false
-      end
-    end
-  end
-
-  module ActiveStorage
-    class Service
-      private
-      def content_disposition_with(type: "inline", filename:)
-        disposition = (type.to_s.presence_in(%w( attachment inline )) || "inline")
-        ActionDispatch::Http::ContentDisposition.format(disposition: disposition, filename: filename.sanitized)
-      end
-    end
-  end
-end

lib/mini_sql_multisite_connection.rb

@@ -36,6 +36,9 @@ class MiniSqlMultisiteConnection < MiniSql::Postgres::Connection
 
     def before_committed!(*); end
     def rolledback!(*); end
+    def trigger_transactional_callbacks?
+      true
+    end
   end
 
   # Allows running arbitrary code after the current transaction has been committed.