Merge branch 'master' into laurocaetano-fix_send_file

* master: (536 commits)
  doc, API example on how to use `Model#exists?` with multiple IDs. [ci skip]
  Restore DATABASE_URL even if it's nil in connection_handler test
  [ci skip] - error_messages_for has been deprecated since 2.3.8 - lets reduce any confusion for users
  Ensure Active Record connection consistency
  Revert "ask the fixture set for the sql statements"
  Check `respond_to` before delegation due to: https://github.com/ruby/ruby/commit/d781caaf313b8649948c107bba277e5ad7307314
  Adding Hash#compact and Hash#compact! methods
  MySQL version 4.1 was EOL on December 31, 2009 We should at least recommend modern versions of MySQL to users.
  clear cache on body close so that cache remains during rendering
  add a more restricted codepath for templates fixes #13390
  refactor generator tests to use block form of Tempfile
  Fix typo [ci skip]
  Move finish_template as the last public method in the generator
  Minor typos fix [ci skip]
  make `change_column_null` reversible. Closes #13576.
  create/drop test and development databases only if RAILS_ENV is nil
  Revert "Speedup String#to"
  typo fix in test name. [ci skip].
  `core_ext/string/access.rb` test what we are documenting.
  Fix typo in image_tag documentation
  ...

Conflicts:
	actionpack/CHANGELOG.md

3 files changed, 76 insertions, 68 deletions

diff --git a/activerecord/test/cases/relation/delegation_test.rb b/activerecord/test/cases/relation/delegation_test.rb
index 13677797cf..9b2bfed039 100644
--- a/activerecord/test/cases/relation/delegation_test.rb
+++ b/activerecord/test/cases/relation/delegation_test.rb
@@ -6,95 +6,63 @@ module ActiveRecord
   class DelegationTest < ActiveRecord::TestCase
     fixtures :posts
 
-    def assert_responds(target, method)
-      assert target.respond_to?(method)
-      assert_nothing_raised do
-        method_arity = target.to_a.method(method).arity
+    def call_method(target, method)
+      method_arity = target.to_a.method(method).arity
 
-        if method_arity.zero?
-          target.send(method)
-        elsif method_arity < 0
-          if method == :shuffle!
-            target.send(method)
-          else
-            target.send(method, 1)
-          end
+      if method_arity.zero?
+        target.public_send(method)
+      elsif method_arity < 0
+        if method == :shuffle!
+          target.public_send(method)
         else
-          raise NotImplementedError
+          target.public_send(method, 1)
         end
+       elsif method_arity == 1
+        target.public_send(method, 1)
+      else
+        raise NotImplementedError
       end
     end
   end
 
-  class DelegationAssociationTest < DelegationTest
-    def target
-      Post.first.comments
-    end
+  module DelegationWhitelistBlacklistTests
+    ARRAY_DELEGATES = [
+      :+, :-, :|, :&, :[],
+      :all?, :collect, :detect, :each, :each_cons, :each_with_index,
+      :exclude?, :find_all, :flat_map, :group_by, :include?, :length,
+      :map, :none?, :one?, :partition, :reject, :reverse,
+      :sample, :second, :sort, :sort_by, :third,
+      :to_ary, :to_set, :to_xml, :to_yaml
+    ]
 
-    [:map, :collect].each do |method|
-      test "##{method} is delegated" do
-        assert_responds(target, method)
-        assert_equal(target.pluck(:body), target.send(method) {|post| post.body })
-      end
-
-      test "##{method}! is not delegated" do
-        assert_deprecated do
-          assert_responds(target, "#{method}!")
-        end
+    ARRAY_DELEGATES.each do |method|
+      define_method "test_delegates_#{method}_to_Array" do
+        assert_respond_to target, method
       end
     end
 
-    [:compact!, :flatten!, :reject!, :reverse!, :rotate!,
-      :shuffle!, :slice!, :sort!, :sort_by!].each do |method|
-      test "##{method} delegation is deprecated" do
-        assert_deprecated do
-          assert_responds(target, method)
-        end
-      end
-    end
-
-    [:select!, :uniq!].each do |method|
-      test "##{method} is implemented" do
-        assert_responds(target, method)
+    ActiveRecord::Delegation::BLACKLISTED_ARRAY_METHODS.each do |method|
+      define_method "test_#{method}_is_not_delegated_to_Array" do
+        assert_raises(NoMethodError) { call_method(target, method) }
       end
     end
   end
 
-  class DelegationRelationTest < DelegationTest
-    fixtures :comments
+  class DelegationAssociationTest < DelegationTest
+    include DelegationWhitelistBlacklistTests
 
     def target
-      Comment.where(body: 'Normal type')
+      Post.first.comments
     end
+  end
 
-    [:map, :collect].each do |method|
-      test "##{method} is delegated" do
-        assert_responds(target, method)
-        assert_equal(target.pluck(:body), target.send(method) {|post| post.body })
-      end
-
-      test "##{method}! is not delegated" do
-        assert_deprecated do
-          assert_responds(target, "#{method}!")
-        end
-      end
-    end
+  class DelegationRelationTest < DelegationTest
+    include DelegationWhitelistBlacklistTests
 
-    [:compact!, :flatten!, :reject!, :reverse!, :rotate!,
-      :shuffle!, :slice!, :sort!, :sort_by!].each do |method|
-      test "##{method} delegation is deprecated" do
-        assert_deprecated do
-          assert_responds(target, method)
-        end
-      end
-    end
+    fixtures :comments
 
-    [:select!, :uniq!].each do |method|
-      test "##{method} triggers an immutable error" do
-        assert_raises ActiveRecord::ImmutableRelation do
-          assert_responds(target, method)
-        end
-      end
+    def target
+      Comment.all
     end
   end
 end
diff --git a/activerecord/test/cases/relation/where_chain_test.rb b/activerecord/test/cases/relation/where_chain_test.rb
index d44b4dfe3d..fd2420cb88 100644
--- a/activerecord/test/cases/relation/where_chain_test.rb
+++ b/activerecord/test/cases/relation/where_chain_test.rb
@@ -23,6 +23,12 @@ module ActiveRecord
       assert_equal([expected], relation.where_values)
     end
 
+    def test_not_with_nil
+      assert_raise ArgumentError do
+        Post.where.not(nil)
+      end
+    end
+
     def test_not_in
       expected = Arel::Nodes::NotIn.new(Post.arel_table[@name], %w[hello goodbye])
       relation = Post.where.not(title: %w[hello goodbye])
diff --git a/activerecord/test/cases/relation/where_test.rb b/activerecord/test/cases/relation/where_test.rb
index 56e4605ccc..937f226b1d 100644
--- a/activerecord/test/cases/relation/where_test.rb
+++ b/activerecord/test/cases/relation/where_test.rb
@@ -35,6 +35,21 @@ module ActiveRecord
       assert_equal Post.where(author_id: 1).to_sql, Post.where(author: author).to_sql
     end
 
+    def test_belongs_to_nil_where
+      assert_equal Post.where(author_id: nil).to_sql, Post.where(author: nil).to_sql
+    end
+
+    def test_belongs_to_array_value_where
+      assert_equal Post.where(author_id: [1,2]).to_sql, Post.where(author: [1,2]).to_sql
+    end
+
+    def test_belongs_to_nested_relation_where
+      expected = Post.where(author_id: Author.where(id: [1,2])).to_sql
+      actual   = Post.where(author:    Author.where(id: [1,2])).to_sql
+
+      assert_equal expected, actual
+    end
+
     def test_belongs_to_nested_where
       parent = Comment.new
       parent.id = 1
@@ -55,6 +70,25 @@ module ActiveRecord
       assert_equal expected.to_sql, actual.to_sql
     end
 
+    def test_polymorphic_nested_array_where
+      treasure = Treasure.new
+      treasure.id = 1
+      hidden = HiddenTreasure.new
+      hidden.id = 2
+
+      expected = PriceEstimate.where(estimate_of_type: 'Treasure', estimate_of_id: [treasure, hidden])
+      actual   = PriceEstimate.where(estimate_of: [treasure, hidden])
+
+      assert_equal expected.to_sql, actual.to_sql
+    end
+
+    def test_polymorphic_nested_relation_where
+      expected = PriceEstimate.where(estimate_of_type: 'Treasure', estimate_of_id: Treasure.where(id: [1,2]))
+      actual   = PriceEstimate.where(estimate_of: Treasure.where(id: [1,2]))
+
+      assert_equal expected.to_sql, actual.to_sql
+    end
+
     def test_polymorphic_sti_shallow_where
       treasure = HiddenTreasure.new
       treasure.id = 1