1 files changed, 166 insertions, 0 deletions
diff --git a/spec/models/concerns/group_descendant_spec.rb b/spec/models/concerns/group_descendant_spec.rb
new file mode 100644
index 00000000000..c163fb01a81
--- /dev/null
+++ b/spec/models/concerns/group_descendant_spec.rb
@@ -0,0 +1,166 @@
+require 'spec_helper'
+
+describe GroupDescendant, :nested_groups do
+  let(:parent) { create(:group) }
+  let(:subgroup) { create(:group, parent: parent) }
+  let(:subsub_group) { create(:group, parent: subgroup) }
+
+  def all_preloaded_groups(*groups)
+    groups + [parent, subgroup, subsub_group]
+  end
+
+  context 'for a group' do
+    describe '#hierarchy' do
+      it 'only queries once for the ancestors' do
+        # make sure the subsub_group does not have anything cached
+        test_group = create(:group, parent: subsub_group).reload
+
+        query_count = ActiveRecord::QueryRecorder.new { test_group.hierarchy }.count
+
+        expect(query_count).to eq(1)
+      end
+
+      it 'only queries once for the ancestors when a top is given' do
+        test_group = create(:group, parent: subsub_group).reload
+
+        recorder = ActiveRecord::QueryRecorder.new { test_group.hierarchy(subgroup) }
+        expect(recorder.count).to eq(1)
+      end
+
+      it 'builds a hierarchy for a group' do
+        expected_hierarchy = { parent => { subgroup => subsub_group } }
+
+        expect(subsub_group.hierarchy).to eq(expected_hierarchy)
+      end
+
+      it 'builds a hierarchy upto a specified parent' do
+        expected_hierarchy = { subgroup => subsub_group }
+
+        expect(subsub_group.hierarchy(parent)).to eq(expected_hierarchy)
+      end
+
+      it 'raises an error if specifying a base that is not part of the tree' do
+        expect { subsub_group.hierarchy(build_stubbed(:group)) }
+          .to raise_error('specified top is not part of the tree')
+      end
+    end
+
+    describe '.build_hierarchy' do
+      it 'combines hierarchies until the top' do
+        other_subgroup = create(:group, parent: parent)
+        other_subsub_group = create(:group, parent: subgroup)
+
+        groups = all_preloaded_groups(other_subgroup, subsub_group, other_subsub_group)
+
+        expected_hierarchy = { parent => [other_subgroup, { subgroup => [subsub_group, other_subsub_group] }] }
+
+        expect(described_class.build_hierarchy(groups)).to eq(expected_hierarchy)
+      end
+
+      it 'combines upto a given parent' do
+        other_subgroup = create(:group, parent: parent)
+        other_subsub_group = create(:group, parent: subgroup)
+
+        groups = [other_subgroup, subsub_group, other_subsub_group]
+        groups << subgroup # Add the parent as if it was preloaded
+
+        expected_hierarchy = [other_subgroup, { subgroup => [subsub_group, other_subsub_group] }]
+        expect(described_class.build_hierarchy(groups, parent)).to eq(expected_hierarchy)
+      end
+
+      it 'handles building a tree out of order' do
+        other_subgroup = create(:group, parent: parent)
+        other_subgroup2 = create(:group, parent: parent)
+        other_subsub_group = create(:group, parent: other_subgroup)
+
+        groups = all_preloaded_groups(subsub_group, other_subgroup2, other_subsub_group, other_subgroup)
+        expected_hierarchy = { parent => [{ subgroup => subsub_group }, other_subgroup2, { other_subgroup => other_subsub_group }] }
+
+        expect(described_class.build_hierarchy(groups)).to eq(expected_hierarchy)
+      end
+
+      it 'raises an error if not all elements were preloaded' do
+        expect { described_class.build_hierarchy([subsub_group]) }
+          .to raise_error('parent was not preloaded')
+      end
+    end
+  end
+
+  context 'for a project' do
+    let(:project) { create(:project, namespace: subsub_group) }
+
+    describe '#hierarchy' do
+      it 'builds a hierarchy for a project' do
+        expected_hierarchy = { parent => { subgroup => { subsub_group => project } } }
+
+        expect(project.hierarchy).to eq(expected_hierarchy)
+      end
+
+      it 'builds a hierarchy upto a specified parent' do
+        expected_hierarchy = { subsub_group => project }
+
+        expect(project.hierarchy(subgroup)).to eq(expected_hierarchy)
+      end
+    end
+
+    describe '.build_hierarchy' do
+      it 'combines hierarchies until the top' do
+        other_project = create(:project, namespace: parent)
+        other_subgroup_project = create(:project, namespace: subgroup)
+
+        elements = all_preloaded_groups(other_project, subsub_group, other_subgroup_project)
+
+        expected_hierarchy = { parent => [other_project, { subgroup => [subsub_group, other_subgroup_project] }] }
+
+        expect(described_class.build_hierarchy(elements)).to eq(expected_hierarchy)
+      end
+
+      it 'combines upto a given parent' do
+        other_project = create(:project, namespace: parent)
+        other_subgroup_project = create(:project, namespace: subgroup)
+
+        elements = [other_project, subsub_group, other_subgroup_project]
+        elements << subgroup # Added as if it was preloaded
+
+        expected_hierarchy = [other_project, { subgroup => [subsub_group, other_subgroup_project] }]
+
+        expect(described_class.build_hierarchy(elements, parent)).to eq(expected_hierarchy)
+      end
+
+      it 'merges to elements in the same hierarchy' do
+        expected_hierarchy = { parent => subgroup }
+
+        expect(described_class.build_hierarchy([parent, subgroup])).to eq(expected_hierarchy)
+      end
+
+      it 'merges complex hierarchies' do
+        project = create(:project, namespace: parent)
+        sub_project = create(:project, namespace: subgroup)
+        subsubsub_group = create(:group, parent: subsub_group)
+        subsub_project = create(:project, namespace: subsub_group)
+        subsubsub_project = create(:project, namespace: subsubsub_group)
+        other_subgroup = create(:group, parent: parent)
+        other_subproject = create(:project, namespace: other_subgroup)
+
+        elements = [project, subsubsub_project, sub_project, other_subproject, subsub_project]
+        # Add parent groups as if they were preloaded
+        elements += [other_subgroup, subsubsub_group, subsub_group, subgroup]
+
+        expected_hierarchy = [
+          project,
+          {
+            subgroup => [
+              { subsub_group => [{ subsubsub_group => subsubsub_project }, subsub_project] },
+              sub_project
+            ]
+          },
+          { other_subgroup => other_subproject }
+        ]
+
+        actual_hierarchy = described_class.build_hierarchy(elements, parent)
+
+        expect(actual_hierarchy).to eq(expected_hierarchy)
+      end
+    end
+  end
+end