merged kunzmann, expanded tests, works with multiple has_flags per class

.gitignore

@@ -4,3 +4,7 @@ coverage
 .idea
 .idea/*
 .idea/**/*
+*.gem
+.bundle
+Gemfile.lock
+pkg/*

Gemfile

@@ -0,0 +1,5 @@
+source "http://rubygems.org"
+
+gem 'activesupport', '>3.0.0'
+# Specify your gem's dependencies in flag_shih_tzu.gemspec
+gemspec

README.rdoc

@@ -1,22 +1,22 @@
 =FlagShihTzu
 
-A rails plugin to store a collection of boolean attributes in a single 
+A rails plugin to store a collection of boolean attributes in a single
 ActiveRecord column as a bit field.
 
 http://github.com/xing/flag_shih_tzu
 
 This plugin lets you use a single integer column in an ActiveRecord model
-to store a collection of boolean attributes (flags). Each flag can be used 
-almost in the same way you would use any boolean attribute on an 
+to store a collection of boolean attributes (flags). Each flag can be used
+almost in the same way you would use any boolean attribute on an
 ActiveRecord object.
 
 The benefits:
-* No migrations needed for new boolean attributes. This helps a lot 
+* No migrations needed for new boolean attributes. This helps a lot
   if you have very large db-tables where you want to avoid ALTER TABLE whenever
   possible.
 * Only the one integer column needs to be indexed.
 
-Using FlagShihTzu, you can add new boolean attributes whenever you want, 
+Using FlagShihTzu, you can add new boolean attributes whenever you want,
 without needing any migration. Just add a new flag to the +has_flags+ call.
 
 And just in case you are wondering what "Shih Tzu" means:
@@ -25,20 +25,32 @@ http://en.wikipedia.org/wiki/Shih_Tzu
 
 ==Prerequisites
 
-FlagShihTzu assumes that your ActiveRecord model already has an integer field 
-to store the flags, which should be defined to not allow NULL values and 
-should have a default value of 0 (which means all flags are initially set to 
+FlagShihTzu assumes that your ActiveRecord model already has an integer field
+to store the flags, which should be defined to not allow NULL values and
+should have a default value of 0 (which means all flags are initially set to
 false).
 
-The plugin has been tested with Rails versions from 2.1 to 2.3 and MySQL, 
-PostgreSQL and SQLite3 databases.
+The plugin has been tested with Rails versions from 2.1 to 3.0 and MySQL,
+PostgreSQL and SQLite3 databases. It has been tested with ruby 1.9.2 (with
+Rails 3 only).
 
 
 ==Installation
 
+===As plugin (Rails 2.x, Rails 3)
+
   cd path/to/your/rails-project
   ./script/plugin install git://github.com/xing/flag_shih_tzu.git
 
+===As gem (Rails 3)
+
+Add following line to your Gemfile:
+
+  gem 'flag_shih_tzu', '= 0.1.0.pre'
+
+Make sure to install gem with bundler:
+
+  bundle install
 
 ==Usage
 
@@ -50,24 +62,93 @@ PostgreSQL and SQLite3 databases.
     has_flags 1 => :warpdrive,
               2 => :shields,
               3 => :electrolytes
-
   end
 
-+has_flags+ takes a hash. The keys must be positive integers and represent 
-the position of the bit being used to enable or disable the flag. 
++has_flags+ takes a hash. The keys must be positive integers and represent
+the position of the bit being used to enable or disable the flag.
 <b>The keys must not be changed once in use, or you will get wrong results.</b>
 That is why the plugin forces you to set them explicitly.
 The values are symbols for the flags being created.
 
 
+===Using a custom column name
+
+The default column name to store the flags is 'flags', but you can provide a
+custom column name using the <tt>:column</tt> option. This allows you to use
+different columns for separate flags:
+
+  has_flags 1 => :warpdrive,
+            2 => :shields,
+            3 => :electrolytes,
+            :column => 'features'
+
+  has_flags 1 => :spock, 
+            2 => :scott,
+            3 => :kirk,
+            :column => 'crew'
+
+
+===Generated instance methods
+
+Calling +has_flags+ as shown above creates the following instance methods
+on Spaceship:
+
+  Spaceship#warpdrive
+  Spaceship#warpdrive?
+  Spaceship#warpdrive=
+  Spaceship#shields
+  Spaceship#shields?
+  Spaceship#shields=
+  Spaceship#electrolytes
+  Spaceship#electrolytes?
+  Spaceship#electrolytes=
+
+
+===Generated named scopes
+
+The following named scopes become available:
+
+  Spaceship.warpdrive         # :conditions => "(spaceships.flags in (1,3,5,7))"
+  Spaceship.not_warpdrive     # :conditions => "(spaceships.flags not in (1,3,5,7))"
+  Spaceship.shields           # :conditions => "(spaceships.flags in (2,3,6,7))"
+  Spaceship.not_shields       # :conditions => "(spaceships.flags not in (2,3,6,7))"
+  Spaceship.electrolytes      # :conditions => "(spaceships.flags in (4,5,6,7))"
+  Spaceship.not_electrolytes  # :conditions => "(spaceships.flags not in (4,5,6,7))"
+
+If you do not want the named scopes to be defined, set the
+<tt>:named_scopes</tt> option to false when calling +has_flags+:
+
+  has_flags 1 => :warpdrive, 2 => :shields, 3 => :electrolytes, :named_scopes => false
+
+In a Rails 3 application, FlagShihTzu will use <tt>scope</tt> internally to generate
+the scopes. The option on has_flags is still named <tt>:named_scopes</tt> however.
+
+
+===Examples for using the generated methods
+
+  enterprise = Spaceship.new
+  enterprise.warpdrive = true
+  enterprise.shields = true
+  enterprise.electrolytes = false
+  enterprise.save
+
+  if enterprise.shields?
+    ...
+  end
+
+  Spaceship.warpdrive.find(:all)
+  Spaceship.not_electrolytes.count
+  ...
+
+
 ===How it stores the values
 
 As said, FlagShihTzu uses a single integer column to store the values for all
 the defined flags as a bit field.
 
 The bit position of a flag corresponds to the given key.
 
-This way, we can use bit operators on the stored integer value to set, unset 
+This way, we can use bit operators on the stored integer value to set, unset
 and check individual flags.
 
                 +---+---+---+                +---+---+---+
@@ -94,133 +175,119 @@ and check individual flags.
                 +---+---+---+                +---+---+---+
                 | 1 | 1 | 0 | = 4 + 2 = 6    | 1 | 0 | 1 | = 4 + 1 = 5
                 +---+---+---+                +---+---+---+
-    
+
 Read more about bit fields here: http://en.wikipedia.org/wiki/Bit_field
 
 
-===Using a custom column name
+===Support for manually building conditions
 
-The default column name to store the flags is 'flags', but you can provide a 
-custom column name using the <tt>:column</tt> option:
+The following class methods may support you when manually building
+ActiveRecord conditions:
 
-  has_flags(1 => :warpdrive, :column => 'bits')
+  Spaceship.warpdrive_condition         # "(spaceships.flags in (1,3,5,7))"
+  Spaceship.not_warpdrive_condition     # "(spaceships.flags not in (1,3,5,7))"
+  Spaceship.shields_condition           # "(spaceships.flags in (2,3,6,7))"
+  Spaceship.not_shields_condition       # "(spaceships.flags not in (2,3,6,7))"
+  Spaceship.electrolytes_condition      # "(spaceships.flags in (4,5,6,7))"
+  Spaceship.not_electrolytes_condition  # "(spaceships.flags not in (4,5,6,7))"
+
+These methods also accept a :table_alias option that can be used when 
+generating SQL that references the same table more than once:
 
+  Spaceship.shields_condition(:table_alias => 'evil_spaceships') # "(evil_spaceships.flags in (2,3,6,7))"
 
-===Generated instance methods
 
-Calling +has_flags+ as shown above creates the following instance methods 
-on Spaceship:
+===Choosing a query mode
 
-  Spaceship#warpdrive
-  Spaceship#warpdrive?
-  Spaceship#warpdrive=
-  Spaceship#shields
-  Spaceship#shields?
-  Spaceship#shields=
-  Spaceship#electrolytes
-  Spaceship#electrolytes?
-  Spaceship#electrolytes=
+While the default way of building the SQL conditions uses an IN() list
+(as shown above), this approach will not work well for a high number of flags,
+as the value list for IN() grows.
 
+For MySQL, depending on your MySQL settings, this can even hit the
+'max_allowed_packet' limit with the generated query.
 
-===Generated named scopes
+In this case, consider changing the flag query mode to <tt>:bit_operator</tt>
+instead of <tt>:in_list</tt>, like so:
 
-The following named scopes become available:
+  has_flags 1 => :warpdrive, 
+            2 => :shields, 
+            :flag_query_mode => :bit_operator
+
+This will modify the generated condition and named_scope methods to use bit
+operators in the SQL instead of an IN() list:
+
+  Spaceship.warpdrive_condition         # "(spaceships.flags & 1 = 1)",
+  Spaceship.not_warpdrive_condition     # "(spaceships.flags & 1 = 0)",
+  Spaceship.shields_condition           # "(spaceships.flags & 2 = 2)",
+  Spaceship.not_shields_condition       # "(spaceships.flags & 2 = 0)",
 
   Spaceship.warpdrive         # :conditions => "(spaceships.flags & 1 = 1)"
   Spaceship.not_warpdrive     # :conditions => "(spaceships.flags & 1 = 0)"
   Spaceship.shields           # :conditions => "(spaceships.flags & 2 = 2)"
   Spaceship.not_shields       # :conditions => "(spaceships.flags & 2 = 0)"
-  Spaceship.electrolytes      # :conditions => "(spaceships.flags & 4 = 4)"
-  Spaceship.not_electrolytes  # :conditions => "(spaceships.flags & 4 = 0)"
-
-If you do not want the named scopes to be defined, set the
-<tt>:named_scopes</tt> option to false when calling +has_flags+:
-
-  has_flags(1 => :warpdrive, 2 => :shields, 3 => :electrolytes, :named_scopes => false)
-
-
-===Support for manually building conditions
 
-The following class methods may support you when manually building 
-ActiveRecord conditions:
-
-  Spaceship.warpdrive_condition         # "(spaceships.flags & 1 = 1)"
-  Spaceship.not_warpdrive_condition     # "(spaceships.flags & 1 = 0)"
-  Spaceship.shields_condition           # "(spaceships.flags & 2 = 2)"
-  Spaceship.not_shields_condition       # "(spaceships.flags & 2 = 0)"
-  Spaceship.electrolytes_condition      # "(spaceships.flags & 4 = 4)"
-  Spaceship.not_electrolytes_condition  # "(spaceships.flags & 4 = 0)"
-
-
-===Example code
-
-  enterprise = Spaceship.new
-  enterprise.warpdrive = true
-  enterprise.shields = true
-  enterprise.electrolytes = false
-  enterprise.save
-
-  if enterprise.shields?
-    ...
-  end
-
-  Spaceship.warpdrive.find(:all)
-  Spaceship.not_electrolytes.count
-  ...
+The drawback is that due to the bit operator, this query can not use an index
+on the flags column.
 
 
 ==Running the plugin tests
 
+1. (Rails 3 only) Add <tt>mysql2</tt>, <tt>pg</tt> and <tt>sqlite3</tt> gems to your Gemfile.
+1. Install flag_shih_tzu as plugin inside working Rails application.
 1. Modify <tt>test/database.yml</tt> to fit your test environment.
 2. If needed, create the test database you configured in <tt>test/database.yml</tt>.
 
-Then you can run 
-    
-  DB=mysql|postgres|sqlite3 rake test:plugins PLUGIN=flag_shih_tzu 
-    
+Then you can run
+
+  DB=mysql|postgres|sqlite3 rake test:plugins PLUGIN=flag_shih_tzu
+
 from your Rails project root or
-    
-  DB=mysql|postgres|sqlite3 rake 
-    
+
+  DB=mysql|postgres|sqlite3 rake
+
 from <tt>vendor/plugins/flag_shih_tzu</tt>.
 
 
 ==Authors
 
-{Patryk Peszko}[http://github.com/ppeszko], 
-{Sebastian Roebke}[http://github.com/boosty], 
-{David Anderson}[http://github.com/alpinegizmo] 
+{Patryk Peszko}[http://github.com/ppeszko],
+{Sebastian Roebke}[http://github.com/boosty],
+{David Anderson}[http://github.com/alpinegizmo]
 and {Tim Payton}[http://github.com/dizzy42]
 
-Please find out more about our work in our 
+Please find out more about our work in our
 {tech blog}[http://blog.xing.com/category/english/tech-blog].
 
 
 ==Contributors
 
-{TobiTobes}[http://github.com/rngtng], 
+{TobiTobes}[http://github.com/rngtng],
 {Martin Stannard}[http://github.com/martinstannard],
 {Ladislav Martincik}[http://github.com/lacomartincik],
 {Peter Boling}[http://github.com/pboling],
-{Thorsten Boettger}[http://github.com/alto]
+{Daniel Jagszent}[http://github.com/d--j],
+{Thorsten Boettger}[http://github.com/alto],
+{Darren Torpey}[http://github.com/darrentorpey],
+{Joost Baaij}[http://github.com/tilsammans] and
+{Musy Bite}[http://github.com/musybite]
 
 
 ==License
 
 The MIT License
- 
+
 Copyright (c) 2009 {XING AG}[http://www.xing.com/]
- 
+
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
 in the Software without restriction, including without limitation the rights
 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 copies of the Software, and to permit persons to whom the Software is
 furnished to do so, subject to the following conditions:
- 
+
 The above copyright notice and this permission notice shall be included in
 all copies or substantial portions of the Software.
- 
+
 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

Rakefile

@@ -1,6 +1,9 @@
 require 'rake'
 require 'rake/testtask'
-require 'rake/rdoctask'
+require 'rdoc/task'
+
+require 'bundler'
+Bundler::GemHelper.install_tasks
 
 desc 'Default: run unit tests.'
 task :default => :test
@@ -13,7 +16,7 @@ Rake::TestTask.new(:test) do |t|
 end
 
 desc 'Generate documentation for the flag_shih_tzu plugin.'
-Rake::RDocTask.new(:rdoc) do |rdoc|
+RDoc::Task.new do |rdoc|
   rdoc.rdoc_dir = 'rdoc'
   rdoc.title    = 'FlagShihTzu'
   rdoc.options << '--line-numbers' << '--inline-source'
@@ -28,4 +31,4 @@ namespace :test do
     system("rcov -Ilib test/*_test.rb")
     system("open coverage/index.html") if PLATFORM['darwin']
   end
-end
+end