Setup multiple milestones

Adds migrations and relationships required to make multiple milestones
possible for issues, merge requests, and epics.

app/models/concerns/issuable.rb

@@ -13,6 +13,7 @@ module Issuable
   include CacheMarkdownField
   include Participable
   include Mentionable
+  include Milestoneable
   include Subscribable
   include StripAttribute
   include Awardable
@@ -56,7 +57,6 @@ module Issuable
     belongs_to :author, class_name: 'User'
     belongs_to :updated_by, class_name: 'User'
     belongs_to :last_edited_by, class_name: 'User'
-    belongs_to :milestone
 
     has_many :notes, as: :noteable, inverse_of: :noteable, dependent: :destroy do # rubocop:disable Cop/ActiveRecordDependent
       def authors_loaded?
@@ -89,18 +89,12 @@ module Issuable
     # to avoid breaking the existing Issuables which may have their descriptions longer
     validates :description, length: { maximum: DESCRIPTION_LENGTH_MAX }, allow_blank: true, on: :create
     validate :description_max_length_for_new_records_is_valid, on: :update
-    validate :milestone_is_valid
 
     before_validation :truncate_description_on_import!
 
     scope :authored, ->(user) { where(author_id: user) }
     scope :recent, -> { reorder(id: :desc) }
     scope :of_projects, ->(ids) { where(project_id: ids) }
-    scope :of_milestones, ->(ids) { where(milestone_id: ids) }
-    scope :any_milestone, -> { where('milestone_id IS NOT NULL') }
-    scope :with_milestone, ->(title) { left_joins_milestones.where(milestones: { title: title }) }
-    scope :any_release, -> { joins_milestone_releases }
-    scope :with_release, -> (tag, project_id) { joins_milestone_releases.where( milestones: { releases: { tag: tag, project_id: project_id } } ) }
     scope :opened, -> { with_state(:opened) }
     scope :only_opened, -> { with_state(:opened) }
     scope :closed, -> { with_state(:closed) }
@@ -118,20 +112,6 @@ module Issuable
     end
     # rubocop:enable GitlabSecurity/SqlInjection
 
-    scope :left_joins_milestones,    -> { joins("LEFT OUTER JOIN milestones ON #{table_name}.milestone_id = milestones.id") }
-    scope :order_milestone_due_desc, -> { left_joins_milestones.reorder(Arel.sql('milestones.due_date IS NULL, milestones.id IS NULL, milestones.due_date DESC')) }
-    scope :order_milestone_due_asc,  -> { left_joins_milestones.reorder(Arel.sql('milestones.due_date IS NULL, milestones.id IS NULL, milestones.due_date ASC')) }
-
-    scope :without_release, -> do
-      joins("LEFT OUTER JOIN milestone_releases ON #{table_name}.milestone_id = milestone_releases.milestone_id")
-        .where('milestone_releases.release_id IS NULL')
-    end
-
-    scope :joins_milestone_releases, -> do
-      joins("JOIN milestone_releases ON #{table_name}.milestone_id = milestone_releases.milestone_id
-             JOIN releases ON milestone_releases.release_id = releases.id").distinct
-    end
-
     scope :without_label, -> { joins("LEFT OUTER JOIN label_links ON label_links.target_type = '#{name}' AND label_links.target_id = #{table_name}.id").where(label_links: { id: nil }) }
     scope :any_label, -> { joins(:label_links).group(:id) }
     scope :join_project, -> { joins(:project) }
@@ -164,10 +144,6 @@ module Issuable
 
     private
 
-    def milestone_is_valid
-      errors.add(:milestone_id, message: "is invalid") if respond_to?(:milestone_id) && milestone_id.present? && !milestone_available?
-    end
-
     def description_max_length_for_new_records_is_valid
       if new_record? && description.length > Issuable::DESCRIPTION_LENGTH_MAX
         errors.add(:description, :too_long, count: Issuable::DESCRIPTION_LENGTH_MAX)
@@ -332,10 +308,6 @@ module Issuable
     project
   end
 
-  def milestone_available?
-    project_id == milestone&.project_id || project.ancestors_upto.compact.include?(milestone&.group)
-  end
-
   def assignee_or_author?(user)
     author_id == user.id || assignees.exists?(user.id)
   end
@@ -482,13 +454,6 @@ module Issuable
   def wipless_title_changed(old_title)
     old_title != title
   end
-
-  ##
-  # Overridden on EE module
-  #
-  def supports_milestone?
-    respond_to?(:milestone_id)
-  end
 end
 
 Issuable.prepend_if_ee('EE::Issuable') # rubocop: disable Cop/InjectEnterpriseEditionModule

app/models/concerns/milestoneable.rb

+# frozen_string_literal: true
+
+# == Milestoneable concern
+#
+# Contains functionality related to objects that can be assigned Milestones
+#
+# Used by Issuable
+#
+module Milestoneable
+  extend ActiveSupport::Concern
+
+  included do
+    belongs_to :milestone
+
+    validate :milestone_is_valid
+
+    after_save :write_to_new_milestone_relationship
+
+    scope :of_milestones, ->(ids) { where(milestone_id: ids) }
+    scope :any_milestone, -> { where('milestone_id IS NOT NULL') }
+    scope :with_milestone, ->(title) { left_joins_milestones.where(milestones: { title: title }) }
+    scope :any_release, -> { joins_milestone_releases }
+    scope :with_release, -> (tag, project_id) { joins_milestone_releases.where( milestones: { releases: { tag: tag, project_id: project_id } } ) }
+
+    scope :left_joins_milestones,    -> { joins("LEFT OUTER JOIN milestones ON #{table_name}.milestone_id = milestones.id") }
+    scope :order_milestone_due_desc, -> { left_joins_milestones.reorder(Arel.sql('milestones.due_date IS NULL, milestones.id IS NULL, milestones.due_date DESC')) }
+    scope :order_milestone_due_asc,  -> { left_joins_milestones.reorder(Arel.sql('milestones.due_date IS NULL, milestones.id IS NULL, milestones.due_date ASC')) }
+
+    scope :without_release, -> do
+      joins("LEFT OUTER JOIN milestone_releases ON #{table_name}.milestone_id = milestone_releases.milestone_id")
+        .where('milestone_releases.release_id IS NULL')
+    end
+
+    scope :joins_milestone_releases, -> do
+      joins("JOIN milestone_releases ON #{table_name}.milestone_id = milestone_releases.milestone_id
+             JOIN releases ON milestone_releases.release_id = releases.id").distinct
+    end
+
+    private
+
+    def milestone_is_valid
+      errors.add(:milestone_id, message: "is invalid") if respond_to?(:milestone_id) && milestone_id.present? && !milestone_available?
+    end
+
+    def write_to_new_milestone_relationship
+      self.milestones = [milestone].compact if supports_milestone? && saved_change_to_milestone_id?
+    end
+  end
+
+  def milestone_available?
+    project_id == milestone&.project_id || project.ancestors_upto.compact.include?(milestone&.group)
+  end
+
+  ##
+  # Overridden on EE module
+  #
+  def supports_milestone?
+    respond_to?(:milestone_id)
+  end
+end
+
+Milestoneable.prepend_if_ee('EE::Milestoneable')

app/models/issue.rb

@@ -33,6 +33,9 @@ class Issue < ApplicationRecord
 
   has_internal_id :iid, scope: :project, init: ->(s) { s&.project&.issues&.maximum(:iid) }
 
+  has_many :issue_milestones
+  has_many :milestones, through: :issue_milestones
+
   has_many :events, as: :target, dependent: :delete_all # rubocop:disable Cop/ActiveRecordDependent
 
   has_many :merge_requests_closing_issues,

app/models/issue_milestone.rb

+# frozen_string_literal: true
+
+class IssueMilestone < ApplicationRecord
+  belongs_to :milestone
+  belongs_to :issue
+end

app/models/merge_request.rb

@@ -35,6 +35,9 @@ class MergeRequest < ApplicationRecord
 
   has_many :merge_request_diffs
 
+  has_many :merge_request_milestones
+  has_many :milestones, through: :merge_request_milestones
+
   has_one :merge_request_diff,
     -> { order('merge_request_diffs.id DESC') }, inverse_of: :merge_request
 

app/models/merge_request_milestone.rb

+# frozen_string_literal: true
+
+class MergeRequestMilestone < ApplicationRecord
+  belongs_to :milestone
+  belongs_to :merge_request
+end

app/models/milestone.rb

@@ -38,6 +38,9 @@ class Milestone < ApplicationRecord
   has_many :merge_requests
   has_many :events, as: :target, dependent: :delete_all # rubocop:disable Cop/ActiveRecordDependent
 
+  has_many :issue_milestones
+  has_many :merge_request_milestones
+
   scope :of_projects, ->(ids) { where(project_id: ids) }
   scope :of_groups, ->(ids) { where(group_id: ids) }
   scope :active, -> { with_state(:active) }

changelogs/unreleased/36032-multiple-milestone-storage.yml

+---
+title: Setup storage for multiple milestones
+merge_request: 22043
+author:
+type: added

db/migrate/20191205212923_support_multiple_milestones_for_issues.rb

+# frozen_string_literal: true
+
+class SupportMultipleMilestonesForIssues < ActiveRecord::Migration[5.2]
+  DOWNTIME = false
+
+  def change
+    create_table :issue_milestones, id: false do |t|
+      t.references :issue, foreign_key: { on_delete: :cascade }, index: { unique: true }, null: false
+      t.references :milestone, foreign_key: { on_delete: :cascade }, index: true, null: false
+    end
+    add_index :issue_milestones, [:issue_id, :milestone_id], unique: true
+  end
+end

db/migrate/20191205212924_support_multiple_milestones_for_merge_requests.rb

+# frozen_string_literal: true
+
+class SupportMultipleMilestonesForMergeRequests < ActiveRecord::Migration[5.2]
+  DOWNTIME = false
+
+  def change
+    create_table :merge_request_milestones, id: false do |t|
+      t.references :merge_request, foreign_key: { on_delete: :cascade }, index: { unique: true }, null: false
+      t.references :milestone, foreign_key: { on_delete: :cascade }, index: true, null: false
+    end
+    add_index :merge_request_milestones, [:merge_request_id, :milestone_id], name: 'index_mrs_milestones_on_mr_id_and_milestone_id', unique: true
+  end
+end

db/schema.rb

@@ -2100,6 +2100,14 @@ ActiveRecord::Schema.define(version: 2019_12_18_225624) do
     t.index ["issue_id"], name: "index_issue_metrics"
   end
 
+  create_table "issue_milestones", id: false, force: :cascade do |t|
+    t.bigint "issue_id", null: false
+    t.bigint "milestone_id", null: false
+    t.index ["issue_id", "milestone_id"], name: "index_issue_milestones_on_issue_id_and_milestone_id", unique: true
+    t.index ["issue_id"], name: "index_issue_milestones_on_issue_id", unique: true
+    t.index ["milestone_id"], name: "index_issue_milestones_on_milestone_id"
+  end
+
   create_table "issue_tracker_data", force: :cascade do |t|
     t.integer "service_id", null: false
     t.datetime_with_timezone "created_at", null: false
@@ -2487,6 +2495,14 @@ ActiveRecord::Schema.define(version: 2019_12_18_225624) do
     t.index ["pipeline_id"], name: "index_merge_request_metrics_on_pipeline_id"
   end
 
+  create_table "merge_request_milestones", id: false, force: :cascade do |t|
+    t.bigint "merge_request_id", null: false
+    t.bigint "milestone_id", null: false
+    t.index ["merge_request_id", "milestone_id"], name: "index_mrs_milestones_on_mr_id_and_milestone_id", unique: true
+    t.index ["merge_request_id"], name: "index_merge_request_milestones_on_merge_request_id", unique: true
+    t.index ["milestone_id"], name: "index_merge_request_milestones_on_milestone_id"
+  end
+
   create_table "merge_request_user_mentions", force: :cascade do |t|
     t.integer "merge_request_id", null: false
     t.integer "note_id"
@@ -4587,6 +4603,8 @@ ActiveRecord::Schema.define(version: 2019_12_18_225624) do
   add_foreign_key "issue_links", "issues", column: "source_id", name: "fk_c900194ff2", on_delete: :cascade
   add_foreign_key "issue_links", "issues", column: "target_id", name: "fk_e71bb44f1f", on_delete: :cascade
   add_foreign_key "issue_metrics", "issues", on_delete: :cascade
+  add_foreign_key "issue_milestones", "issues", on_delete: :cascade
+  add_foreign_key "issue_milestones", "milestones", on_delete: :cascade
   add_foreign_key "issue_tracker_data", "services", on_delete: :cascade
   add_foreign_key "issue_user_mentions", "issues", on_delete: :cascade
   add_foreign_key "issue_user_mentions", "notes", on_delete: :cascade
@@ -4630,6 +4648,8 @@ ActiveRecord::Schema.define(version: 2019_12_18_225624) do
   add_foreign_key "merge_request_metrics", "merge_requests", on_delete: :cascade
   add_foreign_key "merge_request_metrics", "users", column: "latest_closed_by_id", name: "fk_ae440388cc", on_delete: :nullify
   add_foreign_key "merge_request_metrics", "users", column: "merged_by_id", name: "fk_7f28d925f3", on_delete: :nullify
+  add_foreign_key "merge_request_milestones", "merge_requests", on_delete: :cascade
+  add_foreign_key "merge_request_milestones", "milestones", on_delete: :cascade
   add_foreign_key "merge_request_user_mentions", "merge_requests", on_delete: :cascade
   add_foreign_key "merge_request_user_mentions", "notes", on_delete: :cascade
   add_foreign_key "merge_requests", "ci_pipelines", column: "head_pipeline_id", name: "fk_fd82eae0b9", on_delete: :nullify

ee/app/models/concerns/ee/issuable.rb

@@ -18,18 +18,6 @@ module EE
       end
     end
 
-    override :milestone_available?
-    def milestone_available?
-      return true if is_a?(Epic)
-
-      super
-    end
-
-    override :supports_milestone?
-    def supports_milestone?
-      super && !is_a?(Epic)
-    end
-
     def supports_epic?
       is_a?(Issue) && project.group
     end

ee/app/models/concerns/ee/milestoneable.rb

+# frozen_string_literal: true
+
+module EE
+  module Milestoneable
+    extend ActiveSupport::Concern
+    extend ::Gitlab::Utils::Override
+
+    override :milestone_available?
+    def milestone_available?
+      # This is to avoid attempting to set milestone_id in an Epic to nil, which would cause an exception
+      # as Epic doesn't have milestone_id
+      return true if is_a?(Epic)
+
+      super
+    end
+
+    override :supports_milestone?
+    def supports_milestone?
+      super && !is_a?(Epic)
+    end
+  end
+end

ee/spec/models/concerns/ee/issuable_spec.rb

@@ -39,37 +39,6 @@ describe EE::Issuable do
     end
   end
 
-  describe '#milestone_available?' do
-    context 'with Epic' do
-      let(:epic) { create(:epic) }
-
-      it 'returns true' do
-        expect(epic.milestone_available?).to be_truthy
-      end
-    end
-
-    context 'no Epic' do
-      let(:issue) { create(:issue) }
-
-      it 'returns false' do
-        expect(issue.milestone_available?).to be_falsy
-      end
-    end
-  end
-
-  describe '#supports_milestone?' do
-    let(:group)   { create(:group) }
-    let(:project) { create(:project, group: group) }
-
-    context "for epics" do
-      let(:epic) { build(:epic) }
-
-      it 'returns false' do
-        expect(epic.supports_milestone?).to be_falsy
-      end
-    end
-  end
-
   describe '#matches_cross_reference_regex?' do
     context "epic description with long path string" do
       let(:mentionable) { build(:epic, description: "/a" * 50000) }

ee/spec/models/concerns/ee/milestoneable_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe EE::Milestoneable do
+  describe '#milestone_available?' do
+    context 'no Epic' do
+      let(:issue) { create(:issue) }
+
+      it 'returns false' do
+        expect(issue.milestone_available?).to be_falsy
+      end
+    end
+  end
+
+  describe '#supports_milestone?' do
+    let(:group)   { create(:group) }
+    let(:project) { create(:project, group: group) }
+
+    context "for epics" do
+      let(:epic) { build(:epic) }
+
+      it 'returns false' do
+        expect(epic.supports_milestone?).to be_falsy
+      end
+    end
+  end
+end

lib/gitlab/import_export/import_export.yml

@@ -24,6 +24,8 @@ tree:
       - milestone:
         - events:
           - :push_event_payload
+      - issue_milestones:
+          - :milestone
       - resource_label_events:
         - label:
           - :priorities
@@ -57,6 +59,8 @@ tree:
       - milestone:
         - events:
           - :push_event_payload
+      - merge_request_milestones:
+          - :milestone
       - resource_label_events:
         - label:
           - :priorities
@@ -202,6 +206,12 @@ excluded_attributes:
     - :latest_merge_request_diff_id
     - :head_pipeline_id
     - :state_id
+  issue_milestones:
+    - :milestone_id
+    - :issue_id
+  merge_request_milestones:
+    - :milestone_id
+    - :merge_request_id
   award_emoji:
     - :awardable_id
   statuses:

spec/lib/gitlab/import_export/all_models.yml

@@ -6,6 +6,8 @@ issues:
 - assignees
 - updated_by
 - milestone
+- issue_milestones
+- milestones
 - notes
 - resource_label_events
 - sentry_issue
@@ -77,6 +79,8 @@ milestone:
 - boards
 - milestone_releases
 - releases
+- issue_milestones
+- merge_request_milestones
 snippets:
 - author
 - project
@@ -105,6 +109,8 @@ merge_requests:
 - assignee
 - updated_by
 - milestone
+- merge_request_milestones
+- milestones
 - notes
 - resource_label_events
 - label_links
@@ -145,6 +151,12 @@ merge_requests:
 - deployment_merge_requests
 - deployments
 - user_mentions
+issue_milestones:
+- milestone
+- issue
+merge_request_milestones:
+- milestone
+- merge_request
 external_pull_requests:
 - project
 merge_request_diff:

spec/models/concerns/issuable_spec.rb

@@ -53,43 +53,6 @@ describe Issuable do
       it_behaves_like 'validates description length with custom validation'
       it_behaves_like 'truncates the description to its allowed maximum length on import'
     end
-
-    describe 'milestone' do
-      let(:project) { create(:project) }
-      let(:milestone_id) { create(:milestone, project: project).id }
-      let(:params) do
-        {
-          title: 'something',
-          project: project,
-          author: build(:user),
-          milestone_id: milestone_id
-        }
-      end
-
-      subject { issuable_class.new(params) }
-
-      context 'with correct params' do
-        it { is_expected.to be_valid }
-      end
-
-      context 'with empty string milestone' do
-        let(:milestone_id) { '' }
-
-        it { is_expected.to be_valid }
-      end
-
-      context 'with nil milestone id' do
-        let(:milestone_id) { nil }
-
-        it { is_expected.to be_valid }
-      end
-
-      context 'with a milestone id from another project' do
-        let(:milestone_id) { create(:milestone).id }
-
-        it { is_expected.to be_invalid }
-      end
-    end
   end
 
   describe "Scope" do
@@ -141,48 +104,6 @@ describe Issuable do
     end
   end
 
-  describe '#milestone_available?' do
-    let(:group) { create(:group) }
-    let(:project) { create(:project, group: group) }
-    let(:issue) { create(:issue, project: project) }
-
-    def build_issuable(milestone_id)
-      issuable_class.new(project: project, milestone_id: milestone_id)
-    end
-
-    it 'returns true with a milestone from the issue project' do
-      milestone = create(:milestone, project: project)
-
-      expect(build_issuable(milestone.id).milestone_available?).to be_truthy
-    end
-
-    it 'returns true with a milestone from the issue project group' do
-      milestone = create(:milestone, group: group)
-
-      expect(build_issuable(milestone.id).milestone_available?).to be_truthy
-    end
-
-    it 'returns true with a milestone from the the parent of the issue project group' do
-      parent = create(:group)
-      group.update(parent: parent)
-      milestone = create(:milestone, group: parent)
-
-      expect(build_issuable(milestone.id).milestone_available?).to be_truthy
-    end
-
-    it 'returns false with a milestone from another project' do
-      milestone = create(:milestone)
-
-      expect(build_issuable(milestone.id).milestone_available?).to be_falsey
-    end
-
-    it 'returns false with a milestone from another group' do
-      milestone = create(:milestone, group: create(:group))
-
-      expect(build_issuable(milestone.id).milestone_available?).to be_falsey
-    end
-  end
-
   describe ".search" do
     let!(:searchable_issue) { create(:issue, title: "Searchable awesome issue") }
     let!(:searchable_issue2) { create(:issue, title: 'Aw') }
@@ -809,27 +730,6 @@ describe Issuable do
     end
   end
 
-  describe '#supports_milestone?' do
-    let(:group)   { create(:group) }
-    let(:project) { create(:project, group: group) }
-
-    context "for issues" do
-      let(:issue) { build(:issue, project: project) }
-
-      it 'returns true' do
-        expect(issue.supports_milestone?).to be_truthy
-      end
-    end
-
-    context "for merge requests" do
-      let(:merge_request) { build(:merge_request, target_project: project, source_project: project) }
-
-      it 'returns true' do
-        expect(merge_request.supports_milestone?).to be_truthy
-      end
-    end
-  end
-
   describe '#matches_cross_reference_regex?' do
     context "issue description with long path string" do
       let(:mentionable) { build(:issue, description: "/a" * 50000) }
@@ -854,91 +754,4 @@ describe Issuable do
       it_behaves_like 'matches_cross_reference_regex? fails fast'
     end
   end
-
-  describe 'release scopes' do
-    let_it_be(:project) { create(:project) }
-    let(:forked_project) { fork_project(project) }
-
-    let_it_be(:release_1) { create(:release, tag: 'v1.0', project: project) }
-    let_it_be(:release_2) { create(:release, tag: 'v2.0', project: project) }
-    let_it_be(:release_3) { create(:release, tag: 'v3.0', project: project) }
-    let_it_be(:release_4) { create(:release, tag: 'v4.0', project: project) }
-
-    let_it_be(:milestone_1) { create(:milestone, releases: [release_1], title: 'm1', project: project) }
-    let_it_be(:milestone_2) { create(:milestone, releases: [release_1, release_2], title: 'm2', project: project) }
-    let_it_be(:milestone_3) { create(:milestone, releases: [release_2, release_4], title: 'm3', project: project) }
-    let_it_be(:milestone_4) { create(:milestone, releases: [release_3], title: 'm4', project: project) }
-    let_it_be(:milestone_5) { create(:milestone, releases: [release_3], title: 'm5', project: project) }
-    let_it_be(:milestone_6) { create(:milestone, title: 'm6', project: project) }
-
-    let_it_be(:issue_1) { create(:issue, milestone: milestone_1, project: project) }
-    let_it_be(:issue_2) { create(:issue, milestone: milestone_1, project: project) }
-    let_it_be(:issue_3) { create(:issue, milestone: milestone_2, project: project) }
-    let_it_be(:issue_4) { create(:issue, milestone: milestone_5, project: project) }
-    let_it_be(:issue_5) { create(:issue, milestone: milestone_6, project: project) }
-    let_it_be(:issue_6) { create(:issue, project: project) }
-
-    let(:mr_1) { create(:merge_request, milestone: milestone_1, target_project: project, source_project: project) }
-    let(:mr_2) { create(:merge_request, milestone: milestone_3, target_project: project, source_project: forked_project) }
-    let(:mr_3) { create(:merge_request, source_project: project) }
-
-    let_it_be(:issue_items) { Issue.all }
-    let(:mr_items) { MergeRequest.all }
-
-    describe '#without_release' do
-      it 'returns the issues or mrs not tied to any milestone and the ones tied to milestone with no release' do
-        expect(issue_items.without_release).to contain_exactly(issue_5, issue_6)
-        expect(mr_items.without_release).to contain_exactly(mr_3)
-      end
-    end
-
-    describe '#any_release' do
-      it 'returns all issues or all mrs tied to a release' do
-        expect(issue_items.any_release).to contain_exactly(issue_1, issue_2, issue_3, issue_4)
-        expect(mr_items.any_release).to contain_exactly(mr_1, mr_2)
-      end
-    end
-
-    describe '#with_release' do
-      it 'returns the issues tied to a specfic release' do
-        expect(issue_items.with_release('v1.0', project.id)).to contain_exactly(issue_1, issue_2, issue_3)
-      end
-
-      it 'returns the mrs tied to a specific release' do
-        expect(mr_items.with_release('v1.0', project.id)).to contain_exactly(mr_1)
-      end
-
-      context 'when a release has a milestone with one issue and another one with no issue' do
-        it 'returns that one issue' do
-          expect(issue_items.with_release('v2.0', project.id)).to contain_exactly(issue_3)
-        end
-
-        context 'when the milestone with no issue is added as a filter' do
-          it 'returns an empty list' do
-            expect(issue_items.with_release('v2.0', project.id).with_milestone('m3')).to be_empty
-          end
-        end
-
-        context 'when the milestone with the issue is added as a filter' do
-          it 'returns this issue' do
-            expect(issue_items.with_release('v2.0', project.id).with_milestone('m2')).to contain_exactly(issue_3)
-          end
-        end
-      end
-
-      context 'when there is no issue or mr under a specific release' do
-        it 'returns no issue or no mr' do
-          expect(issue_items.with_release('v4.0', project.id)).to be_empty
-          expect(mr_items.with_release('v4.0', project.id)).to be_empty
-        end
-      end
-
-      context 'when a non-existent release tag is passed in' do
-        it 'returns no issue or no mr' do
-          expect(issue_items.with_release('v999.0', project.id)).to be_empty
-          expect(mr_items.with_release('v999.0', project.id)).to be_empty
-        end
-      end
-    end
-  end
 end

spec/models/concerns/milestoneable_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Milestoneable do
+  let(:user) { create(:user) }
+  let(:milestone) { create(:milestone, project: project) }
+
+  shared_examples_for 'an object that can be assigned a milestone' do
+    describe 'Validation' do
+      describe 'milestone' do
+        let(:project) { create(:project, :repository) }
+        let(:milestone_id) { milestone.id }
+
+        subject { milestoneable_class.new(params) }
+
+        context 'with correct params' do
+          it { is_expected.to be_valid }
+        end
+
+        context 'with empty string milestone' do
+          let(:milestone_id) { '' }
+
+          it { is_expected.to be_valid }
+        end
+
+        context 'with nil milestone id' do
+          let(:milestone_id) { nil }
+
+          it { is_expected.to be_valid }
+        end
+
+        context 'with a milestone id from another project' do
+          let(:milestone_id) { create(:milestone).id }
+
+          it { is_expected.to be_invalid }
+        end
+
+        context 'when valid and saving' do
+          it 'copies the value to the new milestones relationship' do
+            subject.save!
+
+            expect(subject.milestones).to match_array([milestone])
+          end
+
+          context 'with old values in milestones relationship' do
+            let(:old_milestone) { create(:milestone, project: project) }
+
+            before do
+              subject.milestone = old_milestone
+              subject.save!
+            end
+
+            it 'replaces old values' do
+              expect(subject.milestones).to match_array([old_milestone])
+
+              subject.milestone = milestone
+              subject.save!
+
+              expect(subject.milestones).to match_array([milestone])
+            end
+
+            it 'can nullify the milestone' do
+              expect(subject.milestones).to match_array([old_milestone])
+
+              subject.milestone = nil
+              subject.save!
+
+              expect(subject.milestones).to match_array([])
+            end
+          end
+        end
+      end
+    end
+
+    describe '#milestone_available?' do
+      let(:group) { create(:group) }
+      let(:project) { create(:project, group: group) }
+      let(:issue) { create(:issue, project: project) }
+
+      def build_milestoneable(milestone_id)
+        milestoneable_class.new(project: project, milestone_id: milestone_id)
+      end
+
+      it 'returns true with a milestone from the issue project' do
+        milestone = create(:milestone, project: project)
+
+        expect(build_milestoneable(milestone.id).milestone_available?).to be_truthy
+      end
+
+      it 'returns true with a milestone from the issue project group' do
+        milestone = create(:milestone, group: group)
+
+        expect(build_milestoneable(milestone.id).milestone_available?).to be_truthy
+      end
+
+      it 'returns true with a milestone from the the parent of the issue project group' do
+        parent = create(:group)
+        group.update(parent: parent)
+        milestone = create(:milestone, group: parent)
+
+        expect(build_milestoneable(milestone.id).milestone_available?).to be_truthy
+      end
+
+      it 'returns false with a milestone from another project' do
+        milestone = create(:milestone)
+
+        expect(build_milestoneable(milestone.id).milestone_available?).to be_falsey
+      end
+
+      it 'returns false with a milestone from another group' do
+        milestone = create(:milestone, group: create(:group))
+
+        expect(build_milestoneable(milestone.id).milestone_available?).to be_falsey
+      end
+    end
+  end
+
+  describe '#supports_milestone?' do
+    let(:group)   { create(:group) }
+    let(:project) { create(:project, group: group) }
+
+    context "for issues" do
+      let(:issue) { build(:issue, project: project) }
+
+      it 'returns true' do
+        expect(issue.supports_milestone?).to be_truthy
+      end
+    end
+
+    context "for merge requests" do
+      let(:merge_request) { build(:merge_request, target_project: project, source_project: project) }
+
+      it 'returns true' do
+        expect(merge_request.supports_milestone?).to be_truthy
+      end
+    end
+  end
+
+  describe 'release scopes' do
+    let_it_be(:project) { create(:project) }
+
+    let_it_be(:release_1) { create(:release, tag: 'v1.0', project: project) }
+    let_it_be(:release_2) { create(:release, tag: 'v2.0', project: project) }
+    let_it_be(:release_3) { create(:release, tag: 'v3.0', project: project) }
+    let_it_be(:release_4) { create(:release, tag: 'v4.0', project: project) }
+
+    let_it_be(:milestone_1) { create(:milestone, releases: [release_1], title: 'm1', project: project) }
+    let_it_be(:milestone_2) { create(:milestone, releases: [release_1, release_2], title: 'm2', project: project) }
+    let_it_be(:milestone_3) { create(:milestone, releases: [release_2, release_4], title: 'm3', project: project) }
+    let_it_be(:milestone_4) { create(:milestone, releases: [release_3], title: 'm4', project: project) }
+    let_it_be(:milestone_5) { create(:milestone, releases: [release_3], title: 'm5', project: project) }
+    let_it_be(:milestone_6) { create(:milestone, title: 'm6', project: project) }
+
+    let_it_be(:issue_1) { create(:issue, milestone: milestone_1, project: project) }
+    let_it_be(:issue_2) { create(:issue, milestone: milestone_1, project: project) }
+    let_it_be(:issue_3) { create(:issue, milestone: milestone_2, project: project) }
+    let_it_be(:issue_4) { create(:issue, milestone: milestone_5, project: project) }
+    let_it_be(:issue_5) { create(:issue, milestone: milestone_6, project: project) }
+    let_it_be(:issue_6) { create(:issue, project: project) }
+
+    let_it_be(:items) { Issue.all }
+
+    describe '#without_release' do
+      it 'returns the issues not tied to any milestone and the ones tied to milestone with no release' do
+        expect(items.without_release).to contain_exactly(issue_5, issue_6)
+      end
+    end
+
+    describe '#any_release' do
+      it 'returns all issues tied to a release' do
+        expect(items.any_release).to contain_exactly(issue_1, issue_2, issue_3, issue_4)
+      end
+    end
+
+    describe '#with_release' do
+      it 'returns the issues tied a specfic release' do
+        expect(items.with_release('v1.0', project.id)).to contain_exactly(issue_1, issue_2, issue_3)
+      end
+
+      context 'when a release has a milestone with one issue and another one with no issue' do
+        it 'returns that one issue' do
+          expect(items.with_release('v2.0', project.id)).to contain_exactly(issue_3)
+        end
+
+        context 'when the milestone with no issue is added as a filter' do
+          it 'returns an empty list' do
+            expect(items.with_release('v2.0', project.id).with_milestone('m3')).to be_empty
+          end
+        end
+
+        context 'when the milestone with the issue is added as a filter' do
+          it 'returns this issue' do
+            expect(items.with_release('v2.0', project.id).with_milestone('m2')).to contain_exactly(issue_3)
+          end
+        end
+      end
+
+      context 'when there is no issue under a specific release' do
+        it 'returns no issue' do
+          expect(items.with_release('v4.0', project.id)).to be_empty
+        end
+      end
+
+      context 'when a non-existent release tag is passed in' do
+        it 'returns no issue' do
+          expect(items.with_release('v999.0', project.id)).to be_empty
+        end
+      end
+    end
+  end
+
+  context 'Issues' do
+    let(:milestoneable_class) { Issue }
+    let(:params) do
+      {
+        title: 'something',
+        project: project,
+        author: user,
+        milestone_id: milestone_id
+      }
+    end
+
+    it_behaves_like 'an object that can be assigned a milestone'
+  end
+
+  context 'MergeRequests' do
+    let(:milestoneable_class) { MergeRequest }
+    let(:params) do
+      {
+        title: 'something',
+        source_project: project,
+        target_project: project,
+        source_branch: 'feature',
+        target_branch: 'master',
+        author: user,
+        milestone_id: milestone_id
+      }
+    end
+
+    it_behaves_like 'an object that can be assigned a milestone'
+  end
+end