Merge branch 'master' into treewip

* master:
  eliminate warnings about multiple primary keys on habtm join tables
  Add methods to array delegation from `Relation`
  Fix button_to's params option to support nested names.
  Dependencies clean up
  Deprecate AC::Parameters#== with a Hash
  Fix AC::Parameters#== with other AC::Parameters
  Tests for AC::Parameters#==
  better docs for ActiveSupport::TestCase#assert_nothing_raised
  remove needless `debug_exception_response_format` config [ci skip]
  partial pass over the API guide [ci skip]
  Fix `unsubscribed` server side behavior
  Use a semaphore to signal message availability
  Fix master build
  Remove github gems from the master bug report templates
  Truncate ActionCable broadcast message to 300 chars
  Remove unused require

2 files changed, 14 insertions, 1 deletions

diff --git a/activerecord/test/cases/associations/has_and_belongs_to_many_associations_test.rb b/activerecord/test/cases/associations/has_and_belongs_to_many_associations_test.rb
index 5c4586da19..bae4197aaf 100644
--- a/activerecord/test/cases/associations/has_and_belongs_to_many_associations_test.rb
+++ b/activerecord/test/cases/associations/has_and_belongs_to_many_associations_test.rb
@@ -146,6 +146,19 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
     assert_equal 1, country.treaties.count
   end
 
+  def test_join_table_composit_primary_key_should_not_warn
+    country = Country.new(:name => 'India')
+    country.country_id = 'c1'
+    country.save!
+
+    treaty = Treaty.new(:name => 'peace')
+    treaty.treaty_id = 't1'
+    warning = capture(:stderr) do
+      country.treaties << treaty
+    end
+    assert_no_match(/WARNING: Rails does not support composite primary key\./, warning)
+  end
+
   def test_has_and_belongs_to_many
     david = Developer.find(1)
 
diff --git a/activerecord/test/schema/schema.rb b/activerecord/test/schema/schema.rb
index b9e0706d60..2a8996f35c 100644
--- a/activerecord/test/schema/schema.rb
+++ b/activerecord/test/schema/schema.rb
@@ -929,7 +929,7 @@ ActiveRecord::Schema.define do
     t.string :treaty_id
     t.string :name
   end
-  create_table :countries_treaties, force: true, id: false do |t|
+  create_table :countries_treaties, force: true, primary_key: [:country_id, :treaty_id] do |t|
     t.string :country_id, null: false
     t.string :treaty_id, null: false
   end