add new git fsck rake task and spec

lib/tasks/gitlab/git.rake

@@ -30,6 +30,16 @@ namespace :gitlab do
       end
     end
 
+    desc 'GitLab | Git | Check all repos integrity'
+    task fsck: :environment do
+      failures = perform_git_cmd(%W(#{Gitlab.config.git.bin_path} fsck --name-objects --no-progress), "Checking integrity")
+      if failures.empty?
+        puts "Done".color(:green)
+      else
+        output_failures(failures)
+      end
+    end
+
     def perform_git_cmd(cmd, message)
       puts "Starting #{message} on all repositories"
 

spec/tasks/gitlab/git_rake_spec.rb

+require 'rake_helper'
+
+describe 'gitlab:git rake tasks' do
+  before do
+    Rake.application.rake_require 'tasks/gitlab/git'
+
+    stub_warn_user_is_not_gitlab
+
+    FileUtils.mkdir(Settings.absolute('tmp/tests/default_storage'))
+  end
+
+  after do
+    FileUtils.rm_rf(Settings.absolute('tmp/tests/default_storage'))
+  end
+
+  describe 'fsck' do
+    let(:storages) do
+      { 'default' => { 'path' => Settings.absolute('tmp/tests/default_storage') } }
+    end
+
+    it 'outputs the right git command' do
+      expect(Kernel).to receive(:system).with('').and_return(true)
+
+      run_rake_task('gitlab:git:fsck')
+    end
+  end
+end