require File.join(File.dirname(__FILE__), 'spec_helper')

context "A new Database" do
  setup do
    @db = Sequel::Database.new(1 => 2, :logger => 3)
  end
  
  specify "should receive options" do
    @db.opts.should == {1 => 2, :logger => 3}  
  end
  
  specify "should set the logger from opts[:logger]" do
    @db.logger.should == 3
  end
  
  specify "should create a connection pool" do
    @db.pool.should be_a_kind_of(ConnectionPool)
    @db.pool.max_size.should == 4
    
    Sequel::Database.new(:max_connections => 10).pool.max_size.should == 10
  end
  
  specify "should pass the supplied block to the connection pool" do
    cc = nil
    d = Sequel::Database.new {1234}
    d.synchronize {|c| cc = c}
    cc.should == 1234
  end
end

context "Database#connect" do
  specify "should raise Sequel::Error::NotImplemented" do
    proc {Sequel::Database.new.connect}.should raise_error(NotImplementedError)
  end
end

context "Database#disconnect" do
  specify "should raise Sequel::Error::NotImplemented" do
    proc {Sequel::Database.new.disconnect}.should raise_error(NotImplementedError)
  end
end

context "Database#uri" do
  setup do
    @c = Class.new(Sequel::Database) do
      set_adapter_scheme :mau
    end
    
    @db = Sequel.connect('mau://user:pass@localhost:9876/maumau')
  end
  
  specify "should return the connection URI for the database" do
    @db.uri.should == 'mau://user:pass@localhost:9876/maumau'
  end
end

context "Database.adapter_scheme" do
  specify "should return the database schema" do
    Sequel::Database.adapter_scheme.should be_nil

    @c = Class.new(Sequel::Database) do
      set_adapter_scheme :mau
    end
    
    @c.adapter_scheme.should == :mau
  end
end

context "Database#dataset" do
  setup do
    @db = Sequel::Database.new
    @ds = @db.dataset
  end
  
  specify "should provide a blank dataset through #dataset" do
    @ds.should be_a_kind_of(Sequel::Dataset)
    @ds.opts.should == {}
    @ds.db.should be(@db)
  end
  
  specify "should provide a #from dataset" do
    d = @db.from(:mau)
    d.should be_a_kind_of(Sequel::Dataset)
    d.sql.should == 'SELECT * FROM mau'
    
    e = @db[:miu]
    e.should be_a_kind_of(Sequel::Dataset)
    e.sql.should == 'SELECT * FROM miu'
  end
  
  specify "should provide a filtered #from dataset if a block is given" do
    d = @db.from(:mau) {:x > 100}
    d.should be_a_kind_of(Sequel::Dataset)
    d.sql.should == 'SELECT * FROM mau WHERE (x > 100)'
  end
  
  specify "should provide a #select dataset" do
    d = @db.select(:a, :b, :c).from(:mau)
    d.should be_a_kind_of(Sequel::Dataset)
    d.sql.should == 'SELECT a, b, c FROM mau'
  end
end

context "Database#execute" do
  specify "should raise Sequel::Error::NotImplemented" do
    proc {Sequel::Database.new.execute('blah blah')}.should raise_error(NotImplementedError)
    proc {Sequel::Database.new << 'blah blah'}.should raise_error(NotImplementedError)
  end
end

context "Database#<<" do
  setup do
    @c = Class.new(Sequel::Database) do
      define_method(:execute) {|sql| sql}
    end
    @db = @c.new({})
  end
  
  specify "should pass the supplied sql to #execute" do
    (@db << "DELETE FROM items").should == "DELETE FROM items"
  end
  
  specify "should accept an array and convert it to SQL" do
    a = %[
      --
      CREATE TABLE items (a integer, /*b integer*/
        b text, c integer);
      DROP TABLE old_items;
    ].split($/)
    (@db << a).should == 
      "CREATE TABLE items (a integer, b text, c integer); DROP TABLE old_items;"
  end
  
  specify "should remove comments and whitespace from arrays" do
    s = %[
      --
      CREATE TABLE items (a integer, /*b integer*/
        b text, c integer); \r\n
      DROP TABLE old_items;
    ].split($/)
    (@db << s).should == 
      "CREATE TABLE items (a integer, b text, c integer); DROP TABLE old_items;"
  end
  
  specify "should not remove comments and whitespace from strings" do
    s = "INSERT INTO items VALUES ('---abc')"
    (@db << s).should == s
  end
end

context "Database#synchronize" do
  setup do
    @db = Sequel::Database.new(:max_connections => 1)
    @db.pool.connection_proc = proc {12345}
  end
  
  specify "should wrap the supplied block in pool.hold" do
    stop = false
    c1, c2 = nil
    t1 = Thread.new {@db.synchronize {|c| c1 = c; while !stop;sleep 0.1;end}}
    while !c1;end
    c1.should == 12345
    t2 = Thread.new {@db.synchronize {|c| c2 = c}}
    sleep 0.2
    @db.pool.available_connections.should be_empty
    c2.should be_nil
    stop = true
    t1.join
    sleep 0.1
    c2.should == 12345
    t2.join
  end
end

context "Database#test_connection" do
  setup do
    @db = Sequel::Database.new
    @test = nil
    @db.pool.connection_proc = proc {@test = rand(100)}
  end
  
  specify "should call pool#hold" do
    @db.test_connection
    @test.should_not be_nil
  end
  
  specify "should return true if successful" do
    @db.test_connection.should be_true
  end
end

class DummyDataset < Sequel::Dataset
  def first
    raise if @opts[:from] == [:a]
    true
  end
end

class DummyDatabase < Sequel::Database
  attr_reader :sqls
  
  def execute(sql)
    @sqls ||= []
    @sqls << sql
  end
  
  def transaction; yield; end

  def dataset
    DummyDataset.new(self)
  end
end

context "Database#create_table" do
  setup do
    @db = DummyDatabase.new
  end
  
  specify "should construct proper SQL" do
    @db.create_table :test do
      primary_key :id, :integer, :null => false
      column :name, :text
      index :name, :unique => true
    end
    @db.sqls.should == [
      'CREATE TABLE test (id integer NOT NULL PRIMARY KEY AUTOINCREMENT, name text)',
      'CREATE UNIQUE INDEX test_name_index ON test (name)'
    ]
  end
end

context "Database#alter_table" do
  setup do
    @db = DummyDatabase.new
  end
  
  specify "should construct proper SQL" do
    @db.alter_table :xyz do
      add_column :aaa, :text, :null => false, :unique => true
      drop_column :bbb
      rename_column :ccc, :ddd
      set_column_type :eee, :integer
      set_column_default :hhh, 'abcd'
      
      add_index :fff, :unique => true
      drop_index :ggg
    end
    
    @db.sqls.should == [
      'ALTER TABLE xyz ADD COLUMN aaa text UNIQUE NOT NULL',
      'ALTER TABLE xyz DROP COLUMN bbb',
      'ALTER TABLE xyz RENAME COLUMN ccc TO ddd',
      'ALTER TABLE xyz ALTER COLUMN eee TYPE integer',
      "ALTER TABLE xyz ALTER COLUMN hhh SET DEFAULT 'abcd'",
      
      'CREATE UNIQUE INDEX xyz_fff_index ON xyz (fff)',
      'DROP INDEX xyz_ggg_index'
    ]
  end
end

context "Database#add_column" do
  setup do
    @db = DummyDatabase.new
  end
  
  specify "should construct proper SQL" do
    @db.add_column :test, :name, :text, :unique => true
    @db.sqls.should == [
      'ALTER TABLE test ADD COLUMN name text UNIQUE'
    ]
  end
end

context "Database#drop_column" do
  setup do
    @db = DummyDatabase.new
  end
  
  specify "should construct proper SQL" do
    @db.drop_column :test, :name
    @db.sqls.should == [
      'ALTER TABLE test DROP COLUMN name'
    ]
  end
end

context "Database#rename_column" do
  setup do
    @db = DummyDatabase.new
  end
  
  specify "should construct proper SQL" do
    @db.rename_column :test, :abc, :def
    @db.sqls.should == [
      'ALTER TABLE test RENAME COLUMN abc TO def'
    ]
  end
end

context "Database#set_column_type" do
  setup do
    @db = DummyDatabase.new
  end
  
  specify "should construct proper SQL" do
    @db.set_column_type :test, :name, :integer
    @db.sqls.should == [
      'ALTER TABLE test ALTER COLUMN name TYPE integer'
    ]
  end
end

context "Database#set_column_default" do
  setup do
    @db = DummyDatabase.new
  end
  
  specify "should construct proper SQL" do
    @db.set_column_default :test, :name, 'zyx'
    @db.sqls.should == [
      "ALTER TABLE test ALTER COLUMN name SET DEFAULT 'zyx'"
    ]
  end
end

context "Database#add_index" do
  setup do
    @db = DummyDatabase.new
  end
  
  specify "should construct proper SQL" do
    @db.add_index :test, :name, :unique => true
    @db.sqls.should == [
      'CREATE UNIQUE INDEX test_name_index ON test (name)'
    ]
  end
  
  specify "should accept multiple columns" do
    @db.add_index :test, [:one, :two]
    @db.sqls.should == [
      'CREATE INDEX test_one_two_index ON test (one, two)'
    ]
  end
end

context "Database#drop_index" do
  setup do
    @db = DummyDatabase.new
  end
  
  specify "should construct proper SQL" do
    @db.drop_index :test, :name
    @db.sqls.should == [
      'DROP INDEX test_name_index'
    ]
  end
  
end

class Dummy2Database < Sequel::Database
  attr_reader :sql
  def execute(sql); @sql = sql; end
  def transaction; yield; end
end

context "Database#drop_table" do
  setup do
    @db = DummyDatabase.new
  end
  
  specify "should construct proper SQL" do
    @db.drop_table :test
    @db.sqls.should == ['DROP TABLE test']
  end
  
  specify "should accept multiple table names" do
    @db.drop_table :a, :bb, :ccc
    @db.sqls.should == [
      'DROP TABLE a',
      'DROP TABLE bb',
      'DROP TABLE ccc'
    ]
  end
end

context "Database#rename_table" do
  setup do
    @db = DummyDatabase.new
  end
  
  specify "should construct proper SQL" do
    @db.rename_table :abc, :xyz
    @db.sqls.should == ['ALTER TABLE abc RENAME TO xyz']
  end
end

context "Database#table_exists?" do
  setup do
    @db = DummyDatabase.new
    @db.stub!(:tables).and_return([:a, :b])
    @db2 = DummyDatabase.new
  end
  
  specify "should use Database#tables if available" do
    @db.table_exists?(:a).should be_true
    @db.table_exists?(:b).should be_true
    @db.table_exists?(:c).should be_false
  end
  
  specify "should otherwise try to select the first record from the table's dataset" do
    @db2.table_exists?(:a).should be_false
    @db2.table_exists?(:b).should be_true
  end
end

class Dummy3Database < Sequel::Database
  attr_reader :sql, :transactions
  def execute(sql); @sql ||= []; @sql << sql; end

  class DummyConnection
    def initialize(db); @db = db; end
    def execute(sql); @db.execute(sql); end
  end
end

context "Database#transaction" do
  setup do
    @db = Dummy3Database.new
    @db.pool.connection_proc = proc {Dummy3Database::DummyConnection.new(@db)}
  end
  
  specify "should wrap the supplied block with BEGIN + COMMIT statements" do
    @db.transaction {@db.execute 'DROP TABLE test;'}
    @db.sql.should == ['BEGIN', 'DROP TABLE test;', 'COMMIT']
  end
  
  specify "should issue ROLLBACK if an exception is raised, and re-raise" do
    @db.transaction {@db.execute 'DROP TABLE test'; raise RuntimeError} rescue nil
    @db.sql.should == ['BEGIN', 'DROP TABLE test', 'ROLLBACK']
    
    proc {@db.transaction {raise RuntimeError}}.should raise_error(RuntimeError)
  end
  
  specify "should issue ROLLBACK if Sequel::Error::Rollback is called in the transaction" do
    @db.transaction do
      @db.drop_table(:a)
      raise Sequel::Error::Rollback
      @db.drop_table(:b)
    end
    
    @db.sql.should == ['BEGIN', 'DROP TABLE a', 'ROLLBACK']
  end
  
  specify "should be re-entrant" do
    stop = false
    cc = nil
    t = Thread.new do
      @db.transaction {@db.transaction {@db.transaction {|c|
        cc = c
        while !stop; sleep 0.1; end
      }}}
    end
    while cc.nil?; sleep 0.1; end
    cc.should be_a_kind_of(Dummy3Database::DummyConnection)
    @db.transactions.should == [t]
    stop = true
    t.join
    @db.transactions.should be_empty
  end
end

class Sequel::Database
  def self.get_adapters; @@adapters; end
end

context "A Database adapter with a scheme" do
  setup do
    class CCC < Sequel::Database
      set_adapter_scheme :ccc
    end
  end

  specify "should be registered in adapters" do
    Sequel::Database.get_adapters[:ccc].should == CCC
  end
  
  specify "should be instantiated when its scheme is specified" do
    c = Sequel::Database.connect('ccc://localhost/db')
    c.should be_a_kind_of(CCC)
    c.opts[:host].should == 'localhost'
    c.opts[:database].should == 'db'
  end
  
  specify "should be accessible through Sequel.connect" do
    c = Sequel.connect 'ccc://localhost/db'
    c.should be_a_kind_of(CCC)
    c.opts[:host].should == 'localhost'
    c.opts[:database].should == 'db'
  end

  specify "should be accessible through Sequel.open" do
    c = Sequel.open 'ccc://localhost/db'
    c.should be_a_kind_of(CCC)
    c.opts[:host].should == 'localhost'
    c.opts[:database].should == 'db'
  end

  ### DEPRECATED
  specify "should be accessible through Sequel()" do
    c = Sequel('ccc://localhost/db')
    c.should be_a_kind_of(CCC)
    c.opts[:host].should == 'localhost'
    c.opts[:database].should == 'db'
  end

  specify "should be accessible through Sequel.<adapter>" do
    class << Sequel
      def_adapter_method(:ccc)
    end
    # invalid parameters
    proc {Sequel.ccc('abc', 'def')}.should raise_error(Sequel::Error)
    
    c = Sequel.ccc('mydb')
    c.should be_a_kind_of(CCC)
    c.opts.should == {:adapter=>:ccc, :database => 'mydb'}
    
    c = Sequel.ccc('mydb', :host => 'localhost')
    c.should be_a_kind_of(CCC)
    c.opts.should == {:adapter=>:ccc, :database => 'mydb', :host => 'localhost'}
    
    c = Sequel.ccc
    c.should be_a_kind_of(CCC)
    c.opts.should == {:adapter=>:ccc}
    
    c = Sequel.ccc(:database => 'mydb', :host => 'localhost')
    c.should be_a_kind_of(CCC)
    c.opts.should == {:adapter=>:ccc, :database => 'mydb', :host => 'localhost'}
  end
  
  specify "should be accessible through Sequel.connect with options" do
    c = Sequel.connect(:adapter => :ccc, :database => 'mydb')
    c.should be_a_kind_of(CCC)
    c.opts.should == {:adapter => :ccc, :database => 'mydb'}
  end
end

context "An unknown database scheme" do
  specify "should raise an error in Sequel::Database.connect" do
    proc {Sequel::Database.connect('ddd://localhost/db')}.should raise_error(Sequel::Error::AdapterNotFound)
  end

  specify "should raise an error in Sequel.connect" do
    proc {Sequel.connect('ddd://localhost/db')}.should raise_error(Sequel::Error::AdapterNotFound)
  end

  specify "should raise an error in Sequel.open" do
    proc {Sequel.open('ddd://localhost/db')}.should raise_error(Sequel::Error::AdapterNotFound)
  end
end

context "A broken adapter (lib is there but the class is not)" do
  setup do
    @fn = File.join(File.dirname(__FILE__), '../lib/sequel_core/adapters/blah.rb')
    FileUtils.touch(@fn)
  end
  
  teardown do
    FileUtils.rm(@fn)
  end
  
  specify "should raise an error" do
    proc {Sequel.connect('blah://blow')}.should raise_error(Sequel::Error::AdapterNotFound)
  end
end

context "Database#uri_to_options" do
  specify "should convert a URI to an options hash" do
    h = Sequel::Database.uri_to_options(URI.parse('ttt://uuu:ppp@192.168.60.1:1234/blah'))
    h[:user].should == 'uuu'
    h[:password].should == 'ppp'
    h[:host].should == '192.168.60.1'
    h[:port].should == 1234
    h[:database].should == 'blah'
  end

  specify "should accept a string and convert it to an options hash" do
    h = Sequel::Database.uri_to_options('ttt://uuu:ppp@192.168.60.1:1234/blah')
    h[:user].should == 'uuu'
    h[:password].should == 'ppp'
    h[:host].should == '192.168.60.1'
    h[:port].should == 1234
    h[:database].should == 'blah'
  end
end

context "A single threaded database" do
  teardown do
    Sequel::Database.single_threaded = false
  end
  
  specify "should use a SingleThreadedPool instead of a ConnectionPool" do
    db = Sequel::Database.new(:single_threaded => true)
    db.pool.should be_a_kind_of(SingleThreadedPool)
  end
  
  specify "should be constructable using :single_threaded => true option" do
    db = Sequel::Database.new(:single_threaded => true)
    db.pool.should be_a_kind_of(SingleThreadedPool)
  end
  
  specify "should be constructable using Database.single_threaded = true" do
    Sequel::Database.single_threaded = true
    db = Sequel::Database.new
    db.pool.should be_a_kind_of(SingleThreadedPool)
  end

  specify "should be constructable using Sequel.single_threaded = true" do
    Sequel.single_threaded = true
    db = Sequel::Database.new
    db.pool.should be_a_kind_of(SingleThreadedPool)
  end
end

context "A single threaded database" do
  setup do
    conn = 1234567
    @db = Sequel::Database.new(:single_threaded => true) do
      conn += 1
    end
  end
  
  specify "should invoke connection_proc only once" do
    @db.pool.hold {|c| c.should == 1234568}
    @db.pool.hold {|c| c.should == 1234568}
  end
  
  specify "should convert an Exception into a RuntimeError" do
    db = Sequel::Database.new(:single_threaded => true) do
      raise Exception
    end
    
    proc {db.pool.hold {|c|}}.should raise_error(RuntimeError)
  end
end

context "A database" do
  setup do
    Sequel::Database.single_threaded = false
  end
  
  teardown do
    Sequel::Database.single_threaded = false
  end
  
  specify "should be either single_threaded? or multi_threaded?" do
    db = Sequel::Database.new(:single_threaded => true)
    db.should be_single_threaded
    db.should_not be_multi_threaded
    
    db = Sequel::Database.new(:max_options => 1)
    db.should_not be_single_threaded
    db.should be_multi_threaded
    
    db = Sequel::Database.new
    db.should_not be_single_threaded
    db.should be_multi_threaded
    
    Sequel::Database.single_threaded = true
    
    db = Sequel::Database.new
    db.should be_single_threaded
    db.should_not be_multi_threaded
    
    db = Sequel::Database.new(:max_options => 4)
    db.should be_single_threaded
    db.should_not be_multi_threaded
  end
  
  specify "should accept a logger object" do
    db = Sequel::Database.new
    s = "I'm a logger"
    db.logger = s
    db.logger.should be(s)
    db.logger = nil
    db.logger.should be_nil
  end
end

context "Database#dataset" do
  setup do
    @db = Sequel::Database.new
  end
  
  specify "should delegate to Dataset#query if block is provided" do
    @d = @db.query {select :x; from :y}
    @d.should be_a_kind_of(Sequel::Dataset)
    @d.sql.should == "SELECT x FROM y"
  end
end

context "Database#fetch" do
  setup do
    @db = Sequel::Database.new
    c = Class.new(Sequel::Dataset) do
      def fetch_rows(sql); yield({:sql => sql}); end
    end
    @db.meta_def(:dataset) {c.new(self)}
  end
  
  specify "should create a dataset and invoke its fetch_rows method with the given sql" do
    sql = nil
    @db.fetch('select * from xyz') {|r| sql = r[:sql]}
    sql.should == 'select * from xyz'
  end
  
  specify "should format the given sql with any additional arguments" do
    sql = nil
    @db.fetch('select * from xyz where x = ? and y = ?', 15, 'abc') {|r| sql = r[:sql]}
    sql.should == "select * from xyz where x = 15 and y = 'abc'"
    
    # and Aman Gupta's example
    @db.fetch('select name from table where name = ? or id in (?)',
    'aman', [3,4,7]) {|r| sql = r[:sql]}
    sql.should == "select name from table where name = 'aman' or id in (3, 4, 7)"
  end
  
  specify "should return the dataset if no block is given" do
    @db.fetch('select * from xyz').should be_a_kind_of(Sequel::Dataset)
    
    @db.fetch('select a from b').map {|r| r[:sql]}.should == ['select a from b']

    @db.fetch('select c from d').inject([]) {|m, r| m << r; m}.should == \
      [{:sql => 'select c from d'}]
  end
  
  specify "should return a dataset that always uses the given sql for SELECTs" do
    ds = @db.fetch('select * from xyz')
    ds.select_sql.should == 'select * from xyz'
    ds.sql.should == 'select * from xyz'
    
    ds.filter! {:price < 100}
    ds.select_sql.should == 'select * from xyz'
    ds.sql.should == 'select * from xyz'
  end
end


context "Database#[]" do
  setup do
    @db = Sequel::Database.new
  end
  
  specify "should return a dataset when symbols are given" do
    ds = @db[:items]
    ds.class.should == Sequel::Dataset
    ds.opts[:from].should == [:items]
  end
  
  specify "should return an enumerator when a string is given" do
    c = Class.new(Sequel::Dataset) do
      def fetch_rows(sql); yield({:sql => sql}); end
    end
    @db.meta_def(:dataset) {c.new(self)}

    sql = nil
    @db['select * from xyz where x = ? and y = ?', 15, 'abc'].each {|r| sql = r[:sql]}
    sql.should == "select * from xyz where x = 15 and y = 'abc'"
  end
end

context "Database#create_view" do
  setup do
    @db = DummyDatabase.new
  end
  
  specify "should construct proper SQL with raw SQL" do
    @db.create_view :test, "SELECT * FROM xyz"
    @db.sqls.should == ['CREATE VIEW test AS SELECT * FROM xyz']
  end
  
  specify "should construct proper SQL with dataset" do
    @db.create_view :test, @db[:items].select(:a, :b).order(:c)
    @db.sqls.should == ['CREATE VIEW test AS SELECT a, b FROM items ORDER BY c']
  end
end

context "Database#create_or_replace_view" do
  setup do
    @db = DummyDatabase.new
  end
  
  specify "should construct proper SQL with raw SQL" do
    @db.create_or_replace_view :test, "SELECT * FROM xyz"
    @db.sqls.should == ['CREATE OR REPLACE VIEW test AS SELECT * FROM xyz']
  end

  specify "should construct proper SQL with dataset" do
    @db.create_or_replace_view :test, @db[:items].select(:a, :b).order(:c)
    @db.sqls.should == ['CREATE OR REPLACE VIEW test AS SELECT a, b FROM items ORDER BY c']
  end
end

context "Database#drop_view" do
  setup do
    @db = DummyDatabase.new
  end
  
  specify "should construct proper SQL" do
    @db.drop_view :test
    @db.sqls.should == ['DROP VIEW test']
  end
end

# TODO: beaf this up with specs for all supported ops
context "Database#alter_table_sql" do
  setup do
    @db = DummyDatabase.new
  end
  
  specify "should raise error for an invalid op" do
    proc {@db.alter_table_sql(:mau, :op => :blah)}.should raise_error(Sequel::Error)
  end
end

context "Database.connect" do
  EEE_YAML = "development:\r\n  adapter: eee\r\n  username: mau\r\n  password: tau\r\n  host: alfonso\r\n  database: mydb\r\n"
  
  setup do
    class EEE < Sequel::Database
      set_adapter_scheme :eee
    end
    
    @fn = File.join(File.dirname(__FILE__), 'eee.yaml')
    File.open(@fn, 'wb') {|f| f << EEE_YAML}
  end
  
  teardown do
    FileUtils.rm(@fn)
  end
  
  specify "should accept hashes loaded from YAML files" do
    db = Sequel.connect(YAML.load_file(@fn)['development'])
    db.class.should == EEE
    db.opts[:database].should == 'mydb'
    db.opts[:user].should == 'mau'
    db.opts[:password].should == 'tau'
    db.opts[:host].should == 'alfonso'
  end
end

context "Database#inspect" do
  setup do
    @db = DummyDatabase.new
    
    @db.meta_def(:uri) {'blah://blahblah/blah'}
  end
  
  specify "should include the class name and the connection url" do
    @db.inspect.should == '#<DummyDatabase: "blah://blahblah/blah">'
  end
end

context "Database#get" do
  setup do
    @c = Class.new(DummyDatabase) do
      def dataset
        ds = super
        ds.meta_def(:get) {|c| @db.execute select(c).sql; c}
        ds
      end
    end
    
    @db = @c.new
  end
  
  specify "should use Dataset#get to get a single value" do
    @db.get(1).should == 1
    @db.sqls.last.should == 'SELECT 1'
    
    @db.get(:version[])
    @db.sqls.last.should == 'SELECT version()'
  end
end