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
|
Feature: Int
Checks that an argument is an integer.
```ruby
Contract C::Int => C::Int
```
Background:
Given a file named "int_usage.rb" with:
"""ruby
require "contracts"
C = Contracts
class Integr
include Contracts::Core
Contract C::Int => C::Int
def prev(number)
number - 1
end
end
"""
Scenario: Accepts positive integers
Given a file named "accepts_positive_integers.rb" with:
"""ruby
require "./int_usage"
puts Integr.new.prev(7)
"""
When I run `ruby accepts_positive_integers.rb`
Then output should contain:
"""
6
"""
Scenario: Accepts zero
Given a file named "accepts_zero.rb" with:
"""ruby
require "./int_usage"
puts Integr.new.prev(1)
"""
When I run `ruby accepts_zero.rb`
Then output should contain:
"""
0
"""
Scenario: Accepts negative integers
Given a file named "accepts_negative_integers.rb" with:
"""ruby
require "./int_usage"
puts Integr.new.prev(-1)
"""
When I run `ruby accepts_negative_integers.rb`
Then output should contain:
"""
-2
"""
Scenario: Rejects floats
Given a file named "rejects_floats.rb" with:
"""ruby
require "./int_usage"
puts Integr.new.prev(3.43)
"""
When I run `ruby rejects_floats.rb`
Then output should contain:
"""
: Contract violation for argument 1 of 1: (ParamContractError)
Expected: Int,
Actual: 3.43
Value guarded in: Integr::prev
With Contract: Int => Int
"""
And output should contain "int_usage.rb:8"
Scenario: Rejects other values
Given a file named "rejects_others.rb" with:
"""ruby
require "./int_usage"
puts Integr.new.prev("foo")
"""
When I run `ruby rejects_others.rb`
Then output should contain:
"""
: Contract violation for argument 1 of 1: (ParamContractError)
Expected: Int,
Actual: "foo"
Value guarded in: Integr::prev
With Contract: Int => Int
"""
And output should contain "int_usage.rb:8"
|
