Allow IssuableFinder to filter by closed_at

Signed-off-by: Rémy Coutable <remy@rymai.me>

app/finders/issuable_finder.rb

@@ -94,6 +94,7 @@ class IssuableFinder
     items = by_scope(items)
     items = by_created_at(items)
     items = by_updated_at(items)
+    items = by_closed_at(items)
     items = by_state(items)
     items = by_group(items)
     items = by_assignee(items)
@@ -353,6 +354,13 @@ class IssuableFinder
     items
   end
+  def by_closed_at(items)
+    items = items.closed_after(params[:closed_after]) if params[:closed_after].present?
+    items = items.closed_before(params[:closed_before]) if params[:closed_before].present?
+
+    items
+  end
+
   # rubocop: disable CodeReuse/ActiveRecord
   def by_state(items)
     case params[:state].to_s

app/models/concerns/closed_at_filterable.rb

+# frozen_string_literal: true
+
+module ClosedAtFilterable
+  extend ActiveSupport::Concern
+
+  included do
+    scope :closed_before, ->(date) { where(scoped_table[:closed_at].lteq(date)) }
+    scope :closed_after, ->(date) { where(scoped_table[:closed_at].gteq(date)) }
+
+    def self.scoped_table
+      arel_table.alias(table_name)
+    end
+  end
+end

app/models/concerns/issuable.rb

@@ -23,6 +23,7 @@ module Issuable
   include Sortable
   include CreatedAtFilterable
   include UpdatedAtFilterable
+  include ClosedAtFilterable
   # This object is used to gather issuable meta data for displaying
   # upvotes, downvotes, notes and closing merge requests count for issues and merge requests

spec/finders/issues_finder_spec.rb

@@ -416,6 +416,36 @@ describe IssuesFinder do
         end
       end
+      context 'filtering by closed_at' do
+        let!(:closed_issue1) { create(:issue, project: project1, state: :closed, closed_at: 1.week.ago) }
+        let!(:closed_issue2) { create(:issue, project: project2, state: :closed, closed_at: 1.week.from_now) }
+        let!(:closed_issue3) { create(:issue, project: project2, state: :closed, closed_at: 2.weeks.from_now) }
+
+        context 'through closed_after' do
+          let(:params) { { state: :closed, closed_after: closed_issue3.closed_at } }
+
+          it 'returns issues closed on or after the given date' do
+            expect(issues).to contain_exactly(closed_issue3)
+          end
+        end
+
+        context 'through closed_before' do
+          let(:params) { { state: :closed, closed_before: closed_issue1.closed_at } }
+
+          it 'returns issues closed on or before the given date' do
+            expect(issues).to contain_exactly(closed_issue1)
+          end
+        end
+
+        context 'through closed_after and closed_before' do
+          let(:params) { { state: :closed, closed_after: closed_issue2.closed_at, closed_before: closed_issue3.closed_at } }
+
+          it 'returns issues closed between the given dates' do
+            expect(issues).to contain_exactly(closed_issue2, closed_issue3)
+          end
+        end
+      end
+
       context 'filtering by reaction name' do
         context 'user searches by no reaction' do
           let(:params) { { my_reaction_emoji: 'None' } }