Merge pull request #13 from mcorp/validate_length_of

Matcher to validate size of attribute (resolves #11)

README.md

@@ -28,14 +28,23 @@ class Person
   include Lotus::Validations
 
   attribute :email, presence: true, format: /@/
+  attribute :name, size: 5..50
+  attribute :password, size: 10
 end
 ```
 
 ### Spec
 ```ruby
+# allow_value
 it { is_expected.to allow_value("leo@nospam.org").for(:email) }
 it { is_expected.to_not allow_value('leo-at-nospam.org').for(:email) }
-it { is_expected.to validate_presence_of(:name) }
+
+# presence
+it { is_expected.to validate_presence_of(:email) }
+
+# size
+it { is_expected.to validate_length(:name).is_at_least(5).is_at_most(50) }
+it { is_expected.to validate_length(:password).is_equal_to(10) }
 ```
 
 ## Contributing

lib/shoulda/lotus/matchers.rb

@@ -1,4 +1,5 @@
 require 'shoulda/lotus/matchers/allow_value_matcher'
+require 'shoulda/lotus/matchers/validate_length_of_matcher'
 require 'shoulda/lotus/matchers/validate_presence_of_matcher'
 
 module Shoulda

lib/shoulda/lotus/matchers/validate_length_of_matcher.rb

@@ -0,0 +1,68 @@
+module Shoulda
+  module Lotus
+    module Matchers
+      def validate_length_of(attribute)
+        ValidateLengthOfMatcher.new(attribute)
+      end
+
+      class ValidateLengthOfMatcher
+        def initialize(attribute)
+          @attribute = attribute
+        end
+
+        def matches?(target)
+          errors = []
+
+          @target = target
+
+          @target.send("#{@attribute}=", '*' * (minimum - 1))
+          @target.valid?
+          errors << (@target.errors.for(@attribute).select { |error| error.attribute == @attribute.to_s && error.validation == :size }.size > 0)
+
+          @target.send("#{@attribute}=", '*' * (maximum + 1))
+          @target.valid?
+          errors << (@target.errors.for(@attribute).select { |error| error.attribute == @attribute.to_s && error.validation == :size }.size > 0)
+
+          errors.all? { |error| error }
+        end
+
+        def description
+          "'#{@attribute}' size between '#{@minimum}..#{@maximum}'"
+        end
+
+        def failure_message
+          "'#{@attribute}' is not between '#{@minimum}..#{@maximum}'"
+        end
+
+        def failure_message_when_negated
+          "'#{@attribute}' is between '#{@minimum}..#{@maximum}'"
+        end
+
+        def is_at_least(minimum)
+          @minimum = minimum
+          self
+        end
+
+        def is_at_most(maximum)
+          @maximum = maximum
+          self
+        end
+
+        def is_equal_to(limit)
+          @minimum, @maximum = limit
+          self
+        end
+
+        private
+
+        def minimum
+          @minimum ||= 1
+        end
+
+        def maximum
+          @maximum ||= 1
+        end
+      end
+    end
+  end
+end

lib/shoulda/lotus/version.rb

@@ -1,5 +1,5 @@
 module Shoulda
   module Lotus
-    VERSION = '0.0.2'.freeze
+    VERSION = '0.0.3'.freeze
   end
 end

spec/fixtures/with_validation_length_model.rb

@@ -0,0 +1,6 @@
+class WithValidationLengthModel
+  include Lotus::Validations
+
+  attribute :name_equal_10,     size: 10
+  attribute :name_between_1_10, size: 1..10
+end

spec/shoulda/matchers/validate_length_of_spec.rb

@@ -0,0 +1,35 @@
+require 'spec_helper'
+
+RSpec.describe Shoulda::Lotus::Matchers::ValidateLengthOfMatcher do
+  include Shoulda::Lotus::Matchers
+
+  it '#description' do
+    matcher = validate_length_of(:bar).is_at_least(1).is_at_most(10)
+
+    expect(matcher.description).to eq "'bar' size between '1..10'"
+  end
+
+  context 'an attribute with a validation' do
+    let(:model) { WithValidationLengthModel.new }
+
+    it 'accepts an exact' do
+      expect(model).to validate_length_of(:name_equal_10).is_equal_to(10)
+    end
+
+    it 'accepts an interval' do
+      expect(model).to validate_length_of(:name_between_1_10).is_at_least(1).is_at_most(10)
+    end
+
+    it 'provides correct failure message'
+  end
+
+  context 'an attribute without validation' do
+    let(:model) { WithoutValidationModel.new }
+
+    it 'does not validate' do
+      expect(model).to_not validate_length_of(:email)
+    end
+
+    it 'provides correct failure message'
+  end
+end

spec/spec_helper.rb

@@ -7,4 +7,5 @@
 
 require 'fixtures/without_validation_model'
 require 'fixtures/with_validation_format_model'
+require 'fixtures/with_validation_length_model'
 require 'fixtures/with_validation_presence_model'