1 files changed, 202 insertions, 0 deletions
diff --git a/spec/lib/gitlab/tree_summary_spec.rb b/spec/lib/gitlab/tree_summary_spec.rb
new file mode 100644
index 00000000000..7ffcef2baef
--- /dev/null
+++ b/spec/lib/gitlab/tree_summary_spec.rb
@@ -0,0 +1,202 @@
+require 'spec_helper'
+
+describe Gitlab::TreeSummary do
+  using RSpec::Parameterized::TableSyntax
+
+  let(:project) { create(:project, :empty_repo) }
+  let(:repo) { project.repository }
+  let(:commit) { repo.head_commit }
+
+  let(:path) { nil }
+  let(:offset) { nil }
+  let(:limit) { nil }
+
+  subject(:summary) { described_class.new(commit, project, path: path, offset: offset, limit: limit) }
+
+  describe '#initialize' do
+    it 'defaults offset to 0' do
+      expect(summary.offset).to eq(0)
+    end
+
+    it 'defaults limit to 25' do
+      expect(summary.limit).to eq(25)
+    end
+  end
+
+  describe '#summarize' do
+    let(:project) { create(:project, :custom_repo, files: { 'a.txt' => '' }) }
+
+    subject(:summarized) { summary.summarize }
+
+    it 'returns an array of entries, and an array of commits' do
+      expect(summarized).to be_a(Array)
+      expect(summarized.size).to eq(2)
+
+      entries, commits = *summarized
+      aggregate_failures do
+        expect(entries).to contain_exactly(
+          a_hash_including(file_name: 'a.txt', commit: have_attributes(id: commit.id))
+        )
+
+        expect(commits).to match_array(entries.map { |entry| entry[:commit] })
+      end
+    end
+  end
+
+  describe '#summarize (entries)' do
+    let(:limit) { 2 }
+
+    custom_files = {
+      'a.txt' => '',
+      'b.txt' => '',
+      'directory/c.txt' => ''
+    }
+
+    let(:project) { create(:project, :custom_repo, files: custom_files) }
+    let(:commit) { repo.head_commit }
+
+    subject(:entries) { summary.summarize.first }
+
+    it 'summarizes the entries within the window' do
+      is_expected.to contain_exactly(
+        a_hash_including(type: :tree, file_name: 'directory'),
+        a_hash_including(type: :blob, file_name: 'a.txt')
+        # b.txt is excluded by the limit
+      )
+    end
+
+    it 'references the commit and commit path in entries' do
+      entry = entries.first
+      expected_commit_path = Gitlab::Routing.url_helpers.project_commit_path(project, commit)
+
+      expect(entry[:commit]).to be_a(::Commit)
+      expect(entry[:commit_path]).to eq expected_commit_path
+    end
+
+    context 'in a good subdirectory' do
+      let(:path) { 'directory' }
+
+      it 'summarizes the entries in the subdirectory' do
+        is_expected.to contain_exactly(a_hash_including(type: :blob, file_name: 'c.txt'))
+      end
+    end
+
+    context 'in a non-existent subdirectory' do
+      let(:path) { 'tmp' }
+
+      it { is_expected.to be_empty }
+    end
+
+    context 'custom offset and limit' do
+      let(:offset) { 2 }
+
+      it 'returns entries from the offset' do
+        is_expected.to contain_exactly(a_hash_including(type: :blob, file_name: 'b.txt'))
+      end
+    end
+  end
+
+  describe '#summarize (commits)' do
+    # This is a commit in the master branch of the gitlab-test repository that
+    # satisfies certain assumptions these tests depend on
+    let(:test_commit_sha) { '7975be0116940bf2ad4321f79d02a55c5f7779aa' }
+    let(:whitespace_commit_sha) { '66eceea0db202bb39c4e445e8ca28689645366c5' }
+
+    let(:project) { create(:project, :repository) }
+    let(:commit) { repo.commit(test_commit_sha) }
+    let(:limit) { nil }
+    let(:entries) { summary.summarize.first }
+
+    subject(:commits) do
+      summary.summarize.last
+    end
+
+    it 'returns an Array of ::Commit objects' do
+      is_expected.not_to be_empty
+      is_expected.to all(be_kind_of(::Commit))
+    end
+
+    it 'deduplicates commits when multiple entries reference the same commit' do
+      expect(commits.size).to be < entries.size
+    end
+
+    context 'in a subdirectory' do
+      let(:path) { 'files' }
+
+      it 'returns commits for entries in the subdirectory' do
+        expect(commits).to satisfy_one { |c| c.id == whitespace_commit_sha }
+      end
+    end
+  end
+
+  describe '#more?' do
+    let(:path) { 'tmp/more' }
+
+    where(:num_entries, :offset, :limit, :expected_result) do
+      0 | 0 | 0 | false
+      0 | 0 | 1 | false
+
+      1 | 0 | 0 | true
+      1 | 0 | 1 | false
+      1 | 1 | 0 | false
+      1 | 1 | 1 | false
+
+      2 | 0 | 0 | true
+      2 | 0 | 1 | true
+      2 | 0 | 2 | false
+      2 | 0 | 3 | false
+      2 | 1 | 0 | true
+      2 | 1 | 1 | false
+      2 | 2 | 0 | false
+      2 | 2 | 1 | false
+    end
+
+    with_them do
+      before do
+        create_file('dummy', path: 'other') if num_entries.zero?
+        1.upto(num_entries) { |n| create_file(n, path: path) }
+      end
+
+      subject { summary.more? }
+
+      it { is_expected.to eq(expected_result) }
+    end
+  end
+
+  describe '#next_offset' do
+    let(:path) { 'tmp/next_offset' }
+
+    where(:num_entries, :offset, :limit, :expected_result) do
+      0 | 0 | 0 | 0
+      0 | 0 | 1 | 1
+      0 | 1 | 0 | 1
+      0 | 1 | 1 | 1
+
+      1 | 0 | 0 | 0
+      1 | 0 | 1 | 1
+      1 | 1 | 0 | 1
+      1 | 1 | 1 | 2
+    end
+
+    with_them do
+      before do
+        create_file('dummy', path: 'other')  if num_entries.zero?
+        1.upto(num_entries) { |n| create_file(n, path: path) }
+      end
+
+      subject { summary.next_offset }
+
+      it { is_expected.to eq(expected_result) }
+    end
+  end
+
+  def create_file(unique, path:)
+    repo.create_file(
+      project.creator,
+      "#{path}/file-#{unique}.txt",
+      'content',
+      message: "Commit message #{unique}",
+      branch_name: 'master'
+    )
+  end
+end