From f28eef9a272fd9280416fd8c0984f616ffe102fe Mon Sep 17 00:00:00 2001 From: Jamis Buck Date: Mon, 15 Jan 2007 17:12:32 +0000 Subject: Add Object#acts_like? and Time#acts_like_time? and Date#acts_like_date? to facilitate duck-typing git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@5951 5ecf4fe2-1ee6-0310-87b1-e25e094e27de --- activesupport/CHANGELOG | 2 ++ activesupport/lib/active_support/core_ext/date.rb | 2 ++ .../lib/active_support/core_ext/date/behavior.rb | 13 ++++++++++ .../lib/active_support/core_ext/date_time.rb | 5 ++++ .../lib/active_support/core_ext/object/misc.rb | 9 +++++++ activesupport/lib/active_support/core_ext/time.rb | 2 ++ .../lib/active_support/core_ext/time/behavior.rb | 13 ++++++++++ .../test/core_ext/object_and_class_ext_test.rb | 28 ++++++++++++++++++++++ 8 files changed, 74 insertions(+) create mode 100644 activesupport/lib/active_support/core_ext/date/behavior.rb create mode 100644 activesupport/lib/active_support/core_ext/date_time.rb create mode 100644 activesupport/lib/active_support/core_ext/time/behavior.rb (limited to 'activesupport') diff --git a/activesupport/CHANGELOG b/activesupport/CHANGELOG index 148feff061..f1e40389e9 100644 --- a/activesupport/CHANGELOG +++ b/activesupport/CHANGELOG @@ -1,5 +1,7 @@ *SVN* +* Add Object#acts_like? and Time#acts_like_time? and Date#acts_like_date? to facilitate duck-typing. [Jamis Buck] + * Make 1.months and friends accurate by introducing a Duration class. #6835 [eventualbuddha] * Document Inflector.ordinalize and merge docs from String inflections. #7023 [smeade] diff --git a/activesupport/lib/active_support/core_ext/date.rb b/activesupport/lib/active_support/core_ext/date.rb index effb749c25..9d9051dfbe 100644 --- a/activesupport/lib/active_support/core_ext/date.rb +++ b/activesupport/lib/active_support/core_ext/date.rb @@ -1,8 +1,10 @@ require 'date' +require File.dirname(__FILE__) + '/date/behavior' require File.dirname(__FILE__) + '/date/calculations' require File.dirname(__FILE__) + '/date/conversions' class Date#:nodoc: + include ActiveSupport::CoreExtensions::Date::Behavior include ActiveSupport::CoreExtensions::Date::Calculations include ActiveSupport::CoreExtensions::Date::Conversions end diff --git a/activesupport/lib/active_support/core_ext/date/behavior.rb b/activesupport/lib/active_support/core_ext/date/behavior.rb new file mode 100644 index 0000000000..011cc17cbf --- /dev/null +++ b/activesupport/lib/active_support/core_ext/date/behavior.rb @@ -0,0 +1,13 @@ +module ActiveSupport #:nodoc: + module CoreExtensions #:nodoc: + module Date #:nodoc: + module Behavior + # Enable more predictable duck-typing on Date-like classes. See + # Object#acts_like?. + def acts_like_date? + true + end + end + end + end +end diff --git a/activesupport/lib/active_support/core_ext/date_time.rb b/activesupport/lib/active_support/core_ext/date_time.rb new file mode 100644 index 0000000000..67463d2352 --- /dev/null +++ b/activesupport/lib/active_support/core_ext/date_time.rb @@ -0,0 +1,5 @@ +require "#{File.dirname(__FILE__)}/time/behavior" + +class DateTime + include ActiveSupport::CoreExtensions::Time::Behavior +end \ No newline at end of file diff --git a/activesupport/lib/active_support/core_ext/object/misc.rb b/activesupport/lib/active_support/core_ext/object/misc.rb index ea8e3a1d6a..aae336e6f4 100644 --- a/activesupport/lib/active_support/core_ext/object/misc.rb +++ b/activesupport/lib/active_support/core_ext/object/misc.rb @@ -31,4 +31,13 @@ class Object #:nodoc: def to_json ActiveSupport::JSON.encode(self) end + + # A duck-type assistant method. For example, ActiveSupport extends Date + # to define an acts_like_date? method, and extends Time to define + # acts_like_time?. As a result, we can do "x.acts_like?(:time)" and + # "x.acts_like?(:date)" to do duck-type-safe comparisons, since classes that + # we want to act like Time simply need to define an acts_like_time? method. + def acts_like?(duck) + respond_to? :"acts_like_#{duck}?" + end end \ No newline at end of file diff --git a/activesupport/lib/active_support/core_ext/time.rb b/activesupport/lib/active_support/core_ext/time.rb index 9e3c7a0329..a802c065a7 100644 --- a/activesupport/lib/active_support/core_ext/time.rb +++ b/activesupport/lib/active_support/core_ext/time.rb @@ -1,7 +1,9 @@ +require File.dirname(__FILE__) + '/time/behavior' require File.dirname(__FILE__) + '/time/calculations' require File.dirname(__FILE__) + '/time/conversions' class Time#:nodoc: + include ActiveSupport::CoreExtensions::Time::Behavior include ActiveSupport::CoreExtensions::Time::Calculations include ActiveSupport::CoreExtensions::Time::Conversions end diff --git a/activesupport/lib/active_support/core_ext/time/behavior.rb b/activesupport/lib/active_support/core_ext/time/behavior.rb new file mode 100644 index 0000000000..a5c0baacdf --- /dev/null +++ b/activesupport/lib/active_support/core_ext/time/behavior.rb @@ -0,0 +1,13 @@ +module ActiveSupport #:nodoc: + module CoreExtensions #:nodoc: + module Time #:nodoc: + module Behavior + # Enable more predictable duck-typing on Time-like classes. See + # Object#acts_like?. + def acts_like_time? + true + end + end + end + end +end diff --git a/activesupport/test/core_ext/object_and_class_ext_test.rb b/activesupport/test/core_ext/object_and_class_ext_test.rb index 9daf8d0ac4..e48d87a198 100644 --- a/activesupport/test/core_ext/object_and_class_ext_test.rb +++ b/activesupport/test/core_ext/object_and_class_ext_test.rb @@ -96,6 +96,34 @@ class ObjectTests < Test::Unit::TestCase assert object.respond_to?(:baz) end + class DuckTime + def acts_like_time? + true + end + end + + def test_duck_typing + object = Object.new + time = Time.now + date = Date.today + dt = DateTime.new + duck = DuckTime.new + + assert !object.acts_like?(:time) + assert !object.acts_like?(:date) + + assert time.acts_like?(:time) + assert !time.acts_like?(:date) + + assert !date.acts_like?(:time) + assert date.acts_like?(:date) + + assert dt.acts_like?(:time) + assert dt.acts_like?(:date) + + assert duck.acts_like?(:time) + assert !duck.acts_like?(:date) + end end class ObjectInstanceVariableTest < Test::Unit::TestCase -- cgit v1.2.3