adding mysql adapter test case

activerecord/test/cases/adapters/mysql/mysql_adapter_test.rb

+# encoding: utf-8
+
+require "cases/helper"
+
+module ActiveRecord
+  module ConnectionAdapters
+    class MysqlAdapterTest < ActiveRecord::TestCase
+      def setup
+        @conn = ActiveRecord::Base.connection
+        @conn.exec_query('drop table if exists ex')
+        @conn.exec_query(<<-eosql)
+          CREATE TABLE `ex` (
+            `id` int(11) DEFAULT NULL auto_increment PRIMARY KEY,
+            `number` integer,
+            `data` varchar(255))
+        eosql
+      end
+
+      def test_client_encoding
+        if "<3".respond_to?(:encoding)
+          assert_equal Encoding::UTF_8, @conn.client_encoding
+        else
+          assert_equal 'utf8', @conn.client_encoding
+        end
+      end
+
+      def test_exec_insert_number
+        insert(@conn, 'number' => 10)
+
+        result = @conn.exec_query('SELECT number FROM ex WHERE number = 10')
+
+        assert_equal 1, result.rows.length
+        assert_equal 10, result.rows.last.last
+      end
+
+      def test_exec_insert_string
+        str = 'いただきます！'
+        insert(@conn, 'number' => 10, 'data' => str)
+
+        result = @conn.exec_query('SELECT number, data FROM ex WHERE number = 10')
+
+        value = result.rows.last.last
+
+        if "<3".respond_to?(:encoding)
+          # FIXME: this should probably be inside the mysql AR adapter?
+          value.force_encoding(@conn.client_encoding)
+
+          # The strings in this file are utf-8, so transcode to utf-8
+          value.encode!(Encoding::UTF_8)
+        end
+
+        assert_equal str, value
+      end
+
+      private
+      def insert(ctx, data)
+        binds   = data.map { |name, value|
+          [@conn.columns('ex').find { |x| x.name == name }, value]
+        }
+        columns = binds.map(&:first).map(&:name)
+
+        sql = "INSERT INTO ex (#{columns.join(", ")})
+               VALUES (#{(['?'] * columns.length).join(', ')})"
+
+        ctx.exec_insert(sql, 'SQL', binds)
+      end
+    end
+  end
+end