Added Object#try. ( Taken from http://ozmm.org/posts/try.html ) [Chris Wanstrath]
This commit is contained in:
parent
51a19ae2bf
commit
51730792ca
|
@ -1,5 +1,7 @@
|
|||
*2.3.0 [Edge]*
|
||||
|
||||
* Added Object#try. ( Taken from http://ozmm.org/posts/try.html ) [Chris Wanstrath]
|
||||
|
||||
* Added Enumerable#none? to check that none of the elements match the block #1408 [Damian Janowski]
|
||||
|
||||
* TimeZone offset tests: use current_period, to ensure TimeZone#utc_offset is up-to-date [Geoff Buesing]
|
||||
|
|
|
@ -71,4 +71,17 @@ class Object
|
|||
def acts_like?(duck)
|
||||
respond_to? "acts_like_#{duck}?"
|
||||
end
|
||||
|
||||
# Tries to send the method only if object responds to it. Return +nil+ otherwise.
|
||||
#
|
||||
# ==== Example :
|
||||
#
|
||||
# # Without try
|
||||
# @person ? @person.name : nil
|
||||
#
|
||||
# With try
|
||||
# @person.try(:name)
|
||||
def try(method)
|
||||
send(method) if respond_to?(method, true)
|
||||
end
|
||||
end
|
||||
|
|
|
@ -247,3 +247,28 @@ class ObjectInstanceVariableTest < Test::Unit::TestCase
|
|||
[arg] + instance_exec('bar') { |v| [reverse, v] } }
|
||||
end
|
||||
end
|
||||
|
||||
class ObjectTryTest < Test::Unit::TestCase
|
||||
def setup
|
||||
@string = "Hello"
|
||||
end
|
||||
|
||||
def test_nonexisting_method
|
||||
method = :undefined_method
|
||||
assert !@string.respond_to?(method)
|
||||
assert_nil @string.try(method)
|
||||
end
|
||||
|
||||
def test_valid_method
|
||||
assert_equal 5, @string.try(:size)
|
||||
end
|
||||
|
||||
def test_valid_private_method
|
||||
class << @string
|
||||
private :size
|
||||
end
|
||||
|
||||
assert_equal 5, @string.try(:size)
|
||||
end
|
||||
|
||||
end
|
||||
|
|
Loading…
Reference in New Issue