1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
|
# frozen_string_literal: true
module Contracts
module Engine
# Represents class in question
class Target
# Creates new instance of Target
#
# @param [Class] target - class in question
def initialize(target)
@target = target
end
# Enable contracts engine for target
# - it is no-op if contracts engine is already enabled
# - it automatically enables contracts engine for its eigenclass
# - it sets owner class to target for its eigenclass
#
# @param [Engine::Base:Class] engine_class - type of engine to
# enable (Base or Eigenclass)
def apply(engine_class = Base)
return if applied?
apply_to_eigenclass
eigenclass.class_eval do
define_method(:__contracts_engine) do
@__contracts_engine ||= engine_class.new(self)
end
end
engine.set_eigenclass_owner
end
# Returns true if target has contracts engine already
#
# @return [Bool]
def applied?
target.respond_to?(:__contracts_engine)
end
# Returns contracts engine of target
#
# @return [Engine::Base or Engine::Eigenclass]
def engine
applied? && target.__contracts_engine
end
private
attr_reader :target
def apply_to_eigenclass
return unless meaningless_eigenclass?
self.class.new(eigenclass).apply(Eigenclass)
eigenclass.extend(MethodDecorators)
# FIXME; this should detect what user uses `include Contracts` or
# `include Contracts;;Core`
eigenclass.send(:include, Contracts)
end
def eigenclass
Support.eigenclass_of(target)
end
def meaningless_eigenclass?
!Support.eigenclass?(target)
end
end
end
end
|
