2 # Provides accurate date and time measurements using Date#advance and
3 # Time#advance, respectively. It mainly supports the methods on Numeric,
4 # such as in this example:
6 # 1.month.ago # equivalent to Time.now.advance(:months => -1)
7 class Duration
< BasicObject
8 attr_accessor
:value, :parts
10 def initialize(value
, parts
) #:nodoc:
11 @value, @parts = value
, parts
14 # Adds another Duration or a Numeric to this Duration. Numeric values
15 # are treated as seconds.
18 Duration
.new(value
+ other
.value
, @parts + other
.parts
)
20 Duration
.new(value
+ other
, @parts + [[:seconds, other
]])
24 # Subtracts another Duration or a Numeric from this Duration. Numeric
25 # values are treated as seconds.
31 Duration
.new(-value
, parts
.map
{ |type
,number
| [type
, -number
] })
34 def is_a
?(klass
) #:nodoc:
35 klass
== Duration
|| super
38 # Returns true if <tt>other</tt> is also a Duration instance with the
39 # same <tt>value</tt>, or if <tt>other == value</tt>.
48 def self.===(other
) #:nodoc:
49 other
.is_a
?(Duration
) rescue super
52 # Calculates a new Time or Date that is as far in the future
53 # as this Duration represents.
54 def since(time
= ::Time.current
)
57 alias :from_now :since
59 # Calculates a new Time or Date that is as far in the past
60 # as this Duration represents.
61 def ago(time
= ::Time.current
)
67 consolidated
= parts
.inject(::Hash.new(0)) { |h
,part
| h
[part
.first
] += part
.last
; h
}
68 [:years, :months, :days, :minutes, :seconds].map
do |length
|
69 n
= consolidated
[length
]
70 "#{n} #{n == 1 ? length.to_s.singularize : length.to_s}" if n
.nonzero
?
71 end.compact
.to_sentence
76 def sum(sign
, time
= ::Time.current
) #:nodoc:
77 parts
.inject(time
) do |t
,(type
,number
)|
78 if t
.acts_like
?(:time) || t
.acts_like
?(:date)
80 t
.since(sign
* number
)
82 t
.advance(type
=> sign
* number
)
85 raise ::ArgumentError, "expected a time or date, got #{time.inspect}"
92 def method_missing(method
, *args
, &block
) #:nodoc:
93 value
.send(method
, *args
)