3 files changed, 26 insertions, 24 deletions

diff --git a/activerecord/CHANGELOG.md b/activerecord/CHANGELOG.md
index 6f7b2cb108..e94db776a5 100644
--- a/activerecord/CHANGELOG.md
+++ b/activerecord/CHANGELOG.md
@@ -1,5 +1,10 @@
 ## Rails 4.0.0 (unreleased) ##
 
+*   Use native `mysqldump` command instead of `structure_dump` method
+    when dumping the database structure to a sql file. Fixes #5547.
+
+    *kennyj*
+
 *   Attribute predicate methods, such as `article.title?`, will now raise
     `ActiveModel::MissingAttributeError` if the attribute being queried for
     truthiness was not read from the database, instead of just returning false.
diff --git a/activerecord/lib/active_record/tasks/mysql_database_tasks.rb b/activerecord/lib/active_record/tasks/mysql_database_tasks.rb
index 85d08402f9..4e40a2473b 100644
--- a/activerecord/lib/active_record/tasks/mysql_database_tasks.rb
+++ b/activerecord/lib/active_record/tasks/mysql_database_tasks.rb
@@ -49,19 +49,17 @@ module ActiveRecord
       end
 
       def structure_dump(filename)
-        establish_connection configuration
-        File.open(filename, "w:utf-8") { |f| f << ActiveRecord::Base.connection.structure_dump }
+        args = prepare_command_options('mysqldump')
+        args.concat(["--result-file", "#{filename}"])
+        args.concat(["--no-data"])
+        args.concat(["#{configuration['database']}"])
+        Kernel.system(*args)
       end
 
       def structure_load(filename)
-        args = ['mysql']
-        args.concat(['--user', configuration['username']]) if configuration['username']
-        args << "--password=#{configuration['password']}" if configuration['password']
-        args.concat(['--default-character-set', configuration['charset']]) if configuration['charset']
-        configuration.slice('host', 'port', 'socket', 'database').each do |k, v|
-          args.concat([ "--#{k}", v ]) if v
-        end
+        args = prepare_command_options('mysql')
         args.concat(['--execute', %{SET FOREIGN_KEY_CHECKS = 0; SOURCE #{filename}; SET FOREIGN_KEY_CHECKS = 1}])
+        args.concat(["--database", "#{configuration['database']}"])
         Kernel.system(*args)
       end
 
@@ -113,6 +111,18 @@ IDENTIFIED BY '#{configuration['password']}' WITH GRANT OPTION;
         $stdout.print "Please provide the root password for your mysql installation\n>"
         $stdin.gets.strip
       end
+
+      def prepare_command_options(command)
+        args = [command]
+        args.concat(['--user', configuration['username']]) if configuration['username']
+        args << "--password=#{configuration['password']}"  if configuration['password']
+        args.concat(['--default-character-set', configuration['charset']]) if configuration['charset']
+        configuration.slice('host', 'port', 'socket').each do |k, v|
+          args.concat([ "--#{k}", v ]) if v
+        end
+        args
+      end
+
     end
   end
 end
diff --git a/activerecord/test/cases/tasks/mysql_rake_test.rb b/activerecord/test/cases/tasks/mysql_rake_test.rb
index be591da8d6..eafead66a9 100644
--- a/activerecord/test/cases/tasks/mysql_rake_test.rb
+++ b/activerecord/test/cases/tasks/mysql_rake_test.rb
@@ -219,44 +219,31 @@ module ActiveRecord
 
   class MySQLStructureDumpTest < ActiveRecord::TestCase
     def setup
-      @connection    = stub(:structure_dump => true)
       @configuration = {
         'adapter'  => 'mysql',
         'database' => 'test-db'
       }
-
-      ActiveRecord::Base.stubs(:connection).returns(@connection)
-      ActiveRecord::Base.stubs(:establish_connection).returns(true)
     end
 
     def test_structure_dump
       filename = "awesome-file.sql"
-      ActiveRecord::Base.expects(:establish_connection).with(@configuration)
-      @connection.expects(:structure_dump)
+      Kernel.expects(:system).with("mysqldump", "--result-file", filename, "--no-data", "test-db")
 
       ActiveRecord::Tasks::DatabaseTasks.structure_dump(@configuration, filename)
-      assert File.exists?(filename)
-    ensure
-      FileUtils.rm(filename)
     end
   end
 
   class MySQLStructureLoadTest < ActiveRecord::TestCase
     def setup
-      @connection    = stub
       @configuration = {
         'adapter'  => 'mysql',
         'database' => 'test-db'
       }
-
-      ActiveRecord::Base.stubs(:connection).returns(@connection)
-      ActiveRecord::Base.stubs(:establish_connection).returns(true)
-      Kernel.stubs(:system)
     end
 
     def test_structure_load
       filename = "awesome-file.sql"
-      Kernel.expects(:system).with('mysql', '--database', 'test-db', '--execute', %{SET FOREIGN_KEY_CHECKS = 0; SOURCE #{filename}; SET FOREIGN_KEY_CHECKS = 1})
+      Kernel.expects(:system).with('mysql', '--execute', %{SET FOREIGN_KEY_CHECKS = 0; SOURCE #{filename}; SET FOREIGN_KEY_CHECKS = 1}, "--database", "test-db")
 
       ActiveRecord::Tasks::DatabaseTasks.structure_load(@configuration, filename)
     end