Allow replace non-conditional non-nesting exposures in child classes (fixes #286)

Author: DmitryTsepelev

.rubocop_todo.yml

@@ -18,7 +18,7 @@ Metrics/AbcSize:
 # Offense count: 35
 # Configuration parameters: CountComments, ExcludedMethods.
 Metrics/BlockLength:
- Max: 1489
+ Max: 1496
 
 # Offense count: 2
 # Configuration parameters: CountComments.

CHANGELOG.md

@@ -14,7 +14,8 @@
 #### Fixes
 
 * [#288](https://github.com/ruby-grape/grape-entity/pull/288) Fix wrong argument exception when &:block passed to the expose method - [@DmitryTsepelev](https://github.com/DmitryTsepelev).
-* [#291](https://github.com/ruby-grape/grape-entity/pull/291) Refactor and simplify various classes and modules
+* [#291](https://github.com/ruby-grape/grape-entity/pull/291) Refactor and simplify various classes and modules - [@DmitryTsepelev](https://github.com/DmitryTsepelev).
+* [#292](https://github.com/ruby-grape/grape-entity/pull/292): Allow replace non-conditional non-nesting exposures in child classes (fixes [#286](https://github.com/ruby-grape/grape-entity/issues/286)) - [@DmitryTsepelev](https://github.com/DmitryTsepelev).
 * Your contribution here.
 
 ### 0.6.1 (2017-01-09)

lib/grape_entity/entity.rb

@@ -185,25 +185,24 @@ def self.expose(*args, &block)
 
  @documentation = nil
  @nesting_stack ||= []
+ args.each { |attribute| build_exposure_for_attribute(attribute, @nesting_stack, options, block) }
+ end
 
- # rubocop:disable Style/Next
- args.each do |attribute|
- exposure = Exposure.new(attribute, options)
+ def self.build_exposure_for_attribute(attribute, nesting_stack, options, block)
+ exposure_list = nesting_stack.empty? ? root_exposures : nesting_stack.last.nested_exposures
 
- if @nesting_stack.empty?
- root_exposures << exposure
- else
- @nesting_stack.last.nested_exposures << exposure
- end
+ exposure = Exposure.new(attribute, options)
 
- # Nested exposures are given in a block with no parameters.
- if exposure.nesting?
- @nesting_stack << exposure
- block.call
- @nesting_stack.pop
- end
- end
- # rubocop:enable Style/Next
+ exposure_list.delete_by(attribute) if exposure_list.select_by(attribute).all? { |exp| exp.replaceable_by?(exposure) }
+
+ exposure_list << exposure
+
+ # Nested exposures are given in a block with no parameters.
+ return unless exposure.nesting?
+
+ nesting_stack << exposure
+ block.call
+ nesting_stack.pop
  end
 
  # Returns exposures that have been declared for this Entity on the top level.

lib/grape_entity/exposure/base.rb

@@ -116,6 +116,10 @@ def with_attr_path(entity, options)
  end
  end
 
+ def replaceable_by?(other)
+ !nesting? && !conditional? && !other.nesting? && !other.conditional?
+ end
+
  protected
 
  attr_reader :options

lib/grape_entity/exposure/nesting_exposure/nested_exposures.rb

@@ -16,6 +16,10 @@ def find_by(attribute)
  @exposures.find { |e| e.attribute == attribute }
  end
 
+ def select_by(attribute)
+ @exposures.select { |e| e.attribute == attribute }
+ end
+
  def <<(exposure)
  reset_memoization!
  @exposures << exposure

spec/grape_entity/entity_spec.rb

@@ -352,6 +352,15 @@ class Parent < Person
  expect(subject.represent({ name: 'bar' }, serializable: true)).to eq(email: nil, name: 'bar')
  expect(child_class.represent({ name: 'bar' }, serializable: true)).to eq(email: nil, name: 'foo')
  end
+
+ it 'overrides parent class exposure' do
+ subject.expose :name
+ child_class = Class.new(subject)
+ child_class.expose :name, as: :child_name
+
+ expect(subject.represent({ name: 'bar' }, serializable: true)).to eq(name: 'bar')
+ expect(child_class.represent({ name: 'bar' }, serializable: true)).to eq(child_name: 'bar')
+ end
  end
 
  context 'register formatters' do