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diff --git a/spec/models/concerns/relative_positioning_spec.rb b/spec/models/concerns/relative_positioning_spec.rb
new file mode 100644
index 00000000000..255b584a85e
--- /dev/null
+++ b/spec/models/concerns/relative_positioning_spec.rb
@@ -0,0 +1,204 @@
+require 'spec_helper'
+
+describe Issue, 'RelativePositioning' do
+  let(:project) { create(:empty_project) }
+  let(:issue) { create(:issue, project: project) }
+  let(:issue1) { create(:issue, project: project) }
+  let(:new_issue) { create(:issue, project: project) }
+
+  before do
+    [issue, issue1].each do |issue|
+      issue.move_to_end && issue.save
+    end
+  end
+
+  describe '#max_relative_position' do
+    it 'returns maximum position' do
+      expect(issue.max_relative_position).to eq issue1.relative_position
+    end
+  end
+
+  describe '#prev_relative_position' do
+    it 'returns previous position if there is an issue above' do
+      expect(issue1.prev_relative_position).to eq issue.relative_position
+    end
+
+    it 'returns nil if there is no issue above' do
+      expect(issue.prev_relative_position).to eq nil
+    end
+  end
+
+  describe '#next_relative_position' do
+    it 'returns next position if there is an issue below' do
+      expect(issue.next_relative_position).to eq issue1.relative_position
+    end
+
+    it 'returns nil if there is no issue below' do
+      expect(issue1.next_relative_position).to eq nil
+    end
+  end
+
+  describe '#move_before' do
+    it 'moves issue before' do
+      [issue1, issue].each(&:move_to_end)
+
+      issue.move_before(issue1)
+
+      expect(issue.relative_position).to be < issue1.relative_position
+    end
+  end
+
+  describe '#move_after' do
+    it 'moves issue after' do
+      [issue, issue1].each(&:move_to_end)
+
+      issue.move_after(issue1)
+
+      expect(issue.relative_position).to be > issue1.relative_position
+    end
+  end
+
+  describe '#move_to_end' do
+    it 'moves issue to the end' do
+      new_issue.move_to_end
+
+      expect(new_issue.relative_position).to be > issue1.relative_position
+    end
+  end
+
+  describe '#shift_after?' do
+    it 'returns true' do
+      issue.update(relative_position: issue1.relative_position - 1)
+
+      expect(issue.shift_after?).to be_truthy
+    end
+
+    it 'returns false' do
+      issue.update(relative_position: issue1.relative_position - 2)
+
+      expect(issue.shift_after?).to be_falsey
+    end
+  end
+
+  describe '#shift_before?' do
+    it 'returns true' do
+      issue.update(relative_position: issue1.relative_position + 1)
+
+      expect(issue.shift_before?).to be_truthy
+    end
+
+    it 'returns false' do
+      issue.update(relative_position: issue1.relative_position + 2)
+
+      expect(issue.shift_before?).to be_falsey
+    end
+  end
+
+  describe '#move_between' do
+    it 'positions issue between two other' do
+      new_issue.move_between(issue, issue1)
+
+      expect(new_issue.relative_position).to be > issue.relative_position
+      expect(new_issue.relative_position).to be < issue1.relative_position
+    end
+
+    it 'positions issue between on top' do
+      new_issue.move_between(nil, issue)
+
+      expect(new_issue.relative_position).to be < issue.relative_position
+    end
+
+    it 'positions issue between to end' do
+      new_issue.move_between(issue1, nil)
+
+      expect(new_issue.relative_position).to be > issue1.relative_position
+    end
+
+    it 'positions issues even when after and before positions are the same' do
+      issue1.update relative_position: issue.relative_position
+
+      new_issue.move_between(issue, issue1)
+
+      expect(new_issue.relative_position).to be > issue.relative_position
+      expect(issue.relative_position).to be < issue1.relative_position
+    end
+
+    it 'positions issues between other two if distance is 1' do
+      issue1.update relative_position: issue.relative_position + 1
+
+      new_issue.move_between(issue, issue1)
+
+      expect(new_issue.relative_position).to be > issue.relative_position
+      expect(issue.relative_position).to be < issue1.relative_position
+    end
+
+    it 'positions issue in the middle of other two if distance is big enough' do
+      issue.update relative_position: 6000
+      issue1.update relative_position: 10000
+
+      new_issue.move_between(issue, issue1)
+
+      expect(new_issue.relative_position).to eq(8000)
+    end
+
+    it 'positions issue closer to the middle if we are at the very top' do
+      issue1.update relative_position: 6000
+
+      new_issue.move_between(nil, issue1)
+
+      expect(new_issue.relative_position).to eq(6000 - RelativePositioning::IDEAL_DISTANCE)
+    end
+
+    it 'positions issue closer to the middle if we are at the very bottom' do
+      issue.update relative_position: 6000
+      issue1.update relative_position: nil
+
+      new_issue.move_between(issue, nil)
+
+      expect(new_issue.relative_position).to eq(6000 + RelativePositioning::IDEAL_DISTANCE)
+    end
+
+    it 'positions issue in the middle of other two if distance is not big enough' do
+      issue.update relative_position: 100
+      issue1.update relative_position: 400
+
+      new_issue.move_between(issue, issue1)
+
+      expect(new_issue.relative_position).to eq(250)
+    end
+
+    it 'positions issue in the middle of other two is there is no place' do
+      issue.update relative_position: 100
+      issue1.update relative_position: 101
+
+      new_issue.move_between(issue, issue1)
+
+      expect(new_issue.relative_position).to be_between(issue.relative_position, issue1.relative_position)
+    end
+
+    it 'uses rebalancing if there is no place' do
+      issue.update relative_position: 100
+      issue1.update relative_position: 101
+      issue2 = create(:issue, relative_position: 102, project: project)
+      new_issue.update relative_position: 103
+
+      new_issue.move_between(issue1, issue2)
+      new_issue.save!
+
+      expect(new_issue.relative_position).to be_between(issue1.relative_position, issue2.relative_position)
+      expect(issue.reload.relative_position).not_to eq(100)
+    end
+
+    it 'positions issue right if we pass none-sequential parameters' do
+      issue.update relative_position: 99
+      issue1.update relative_position: 101
+      issue2 = create(:issue, relative_position: 102, project: project)
+      new_issue.update relative_position: 103
+
+      new_issue.move_between(issue, issue2)
+      new_issue.save!
+
+      expect(new_issue.relative_position).to be(100)
+    end
+  end
+end