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
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
|
require 'cases/helper'
module ActiveRecord
class AttributeDecoratorsTest < ActiveRecord::TestCase
class Model < ActiveRecord::Base
self.table_name = 'attribute_decorators_model'
end
class StringDecorator < SimpleDelegator
def initialize(delegate, decoration = "decorated!")
@decoration = decoration
super(delegate)
end
def type_cast_from_user(value)
"#{super} #{@decoration}"
end
alias type_cast_from_database type_cast_from_user
end
setup do
@connection = ActiveRecord::Base.connection
@connection.create_table :attribute_decorators_model, force: true do |t|
t.string :a_string
end
end
teardown do
return unless @connection
@connection.drop_table 'attribute_decorators_model', if_exists: true
Model.attribute_type_decorations.clear
Model.reset_column_information
end
test "attributes can be decorated" do
model = Model.new(a_string: 'Hello')
assert_equal 'Hello', model.a_string
Model.decorate_attribute_type(:a_string, :test) { |t| StringDecorator.new(t) }
model = Model.new(a_string: 'Hello')
assert_equal 'Hello decorated!', model.a_string
end
test "decoration does not eagerly load existing columns" do
Model.reset_column_information
assert_no_queries do
Model.decorate_attribute_type(:a_string, :test) { |t| StringDecorator.new(t) }
end
end
test "undecorated columns are not touched" do
Model.attribute :another_string, Type::String.new, default: 'something or other'
Model.decorate_attribute_type(:a_string, :test) { |t| StringDecorator.new(t) }
assert_equal 'something or other', Model.new.another_string
end
test "decorators can be chained" do
Model.decorate_attribute_type(:a_string, :test) { |t| StringDecorator.new(t) }
Model.decorate_attribute_type(:a_string, :other) { |t| StringDecorator.new(t) }
model = Model.new(a_string: 'Hello!')
assert_equal 'Hello! decorated! decorated!', model.a_string
end
test "decoration of the same type multiple times is idempotent" do
Model.decorate_attribute_type(:a_string, :test) { |t| StringDecorator.new(t) }
Model.decorate_attribute_type(:a_string, :test) { |t| StringDecorator.new(t) }
model = Model.new(a_string: 'Hello')
assert_equal 'Hello decorated!', model.a_string
end
test "decorations occur in order of declaration" do
Model.decorate_attribute_type(:a_string, :test) { |t| StringDecorator.new(t) }
Model.decorate_attribute_type(:a_string, :other) do |type|
StringDecorator.new(type, 'decorated again!')
end
model = Model.new(a_string: 'Hello!')
assert_equal 'Hello! decorated! decorated again!', model.a_string
end
test "decorating attributes does not modify parent classes" do
Model.attribute :another_string, Type::String.new, default: 'whatever'
Model.decorate_attribute_type(:a_string, :test) { |t| StringDecorator.new(t) }
child_class = Class.new(Model)
child_class.decorate_attribute_type(:another_string, :test) { |t| StringDecorator.new(t) }
child_class.decorate_attribute_type(:a_string, :other) { |t| StringDecorator.new(t) }
model = Model.new(a_string: 'Hello!')
child = child_class.new(a_string: 'Hello!')
assert_equal 'Hello! decorated!', model.a_string
assert_equal 'whatever', model.another_string
assert_equal 'Hello! decorated! decorated!', child.a_string
assert_equal 'whatever decorated!', child.another_string
end
class Multiplier < SimpleDelegator
def type_cast_from_user(value)
return if value.nil?
value * 2
end
alias type_cast_from_database type_cast_from_user
end
test "decorating with a proc" do
Model.attribute :an_int, Type::Integer.new
type_is_integer = proc { |_, type| type.type == :integer }
Model.decorate_matching_attribute_types type_is_integer, :multiplier do |type|
Multiplier.new(type)
end
model = Model.new(a_string: 'whatever', an_int: 1)
assert_equal 'whatever', model.a_string
assert_equal 2, model.an_int
end
end
end
|
