Deprecate #connection in favour of accessing it via the class

This allows end-users to have a `connection` method on their models
without clashing with ActiveRecord internals.

2 files changed, 6 insertions, 7 deletions

diff --git a/activerecord/test/cases/fixtures_test.rb b/activerecord/test/cases/fixtures_test.rb
index b0b29f5f42..8ad40ec3f4 100644
--- a/activerecord/test/cases/fixtures_test.rb
+++ b/activerecord/test/cases/fixtures_test.rb
@@ -477,9 +477,8 @@ class CustomConnectionFixturesTest < ActiveRecord::TestCase
   fixtures :courses
   self.use_transactional_fixtures = false
 
-  def test_connection
-    assert_kind_of Course, courses(:ruby)
-    assert_equal Course.connection, courses(:ruby).connection
+  def test_connection_instance_method_deprecation
+    assert_deprecated { courses(:ruby).connection }
   end
 
   def test_leaky_destroy
diff --git a/activerecord/test/cases/transaction_callbacks_test.rb b/activerecord/test/cases/transaction_callbacks_test.rb
index eb4ffd4498..766a5c0c90 100644
--- a/activerecord/test/cases/transaction_callbacks_test.rb
+++ b/activerecord/test/cases/transaction_callbacks_test.rb
@@ -182,9 +182,9 @@ class TransactionCallbacksTest < ActiveRecord::TestCase
   end
 
   def test_call_after_rollback_when_commit_fails
-    @first.connection.class.send(:alias_method, :real_method_commit_db_transaction, :commit_db_transaction)
+    @first.class.connection.class.send(:alias_method, :real_method_commit_db_transaction, :commit_db_transaction)
     begin
-      @first.connection.class.class_eval do
+      @first.class.connection.class.class_eval do
         def commit_db_transaction; raise "boom!"; end
       end
 
@@ -194,8 +194,8 @@ class TransactionCallbacksTest < ActiveRecord::TestCase
       assert !@first.save rescue nil
       assert_equal [:after_rollback], @first.history
     ensure
-      @first.connection.class.send(:remove_method, :commit_db_transaction)
-      @first.connection.class.send(:alias_method, :commit_db_transaction, :real_method_commit_db_transaction)
+      @first.class.connection.class.send(:remove_method, :commit_db_transaction)
+      @first.class.connection.class.send(:alias_method, :commit_db_transaction, :real_method_commit_db_transaction)
     end
   end