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|
Feature: Or
Takes a variable number of contracts. The contract passes if any of the
contracts pass.
```ruby
Contract C::Or[Float, C::Nat] => String
```
This example will validate first argument of a method and accept either
`Float` or natural integer.
Background:
Given a file named "or_usage.rb" with:
"""ruby
require "contracts"
C = Contracts
class Example
include Contracts::Core
Contract C::Or[Float, C::Nat] => String
def nat_string(number)
number.to_i.to_s
end
end
"""
Scenario: Accepts float
Given a file named "accepts_float.rb" with:
"""ruby
require "./or_usage"
puts Example.new.nat_string(3.7)
"""
When I run `ruby accepts_float.rb`
Then output should contain:
"""
3
"""
Scenario: Accepts natural
Given a file named "accepts_natural.rb" with:
"""ruby
require "./or_usage"
puts Example.new.nat_string(7)
"""
When I run `ruby accepts_natural.rb`
Then output should contain:
"""
7
"""
Scenario: Rejects negative integer
Given a file named "rejects_negative_integer.rb" with:
"""ruby
require "./or_usage"
puts Example.new.nat_string(-3)
"""
When I run `ruby rejects_negative_integer.rb`
Then output should contain:
"""
: Contract violation for argument 1 of 1: (ParamContractError)
Expected: (Float or Nat),
Actual: -3
Value guarded in: Example::nat_string
With Contract: Or => String
"""
Scenario: Rejects other values
Given a file named "rejects_other.rb" with:
"""ruby
require "./or_usage"
puts Example.new.nat_string(nil)
"""
When I run `ruby rejects_other.rb`
Then output should contain:
"""
: Contract violation for argument 1 of 1: (ParamContractError)
Expected: (Float or Nat),
Actual: nil
Value guarded in: Example::nat_string
With Contract: Or => String
"""
|
