Add git version to gitlab:env:info

https://gitlab.com/gitlab-org/gitlab-ce/issues/25376

changelogs/unreleased/add-git-version-to-system-info.yml

+---
+title: Add git version to gitlab:env:info
+merge_request: 9128
+author: Semyon Pupkov

lib/tasks/gitlab/info.rake

@@ -14,6 +14,8 @@ namespace :gitlab do
       rake_version = run_and_match(%w(rake --version), /[\d\.]+/).try(:to_s)
       # check redis version
       redis_version = run_and_match(%w(redis-cli --version), /redis-cli (\d+\.\d+\.\d+)/).to_a
+      # check Git version
+      git_version = run_and_match([Gitlab.config.git.bin_path, '--version'], /git version ([\d\.]+)/).to_a
 
       puts ""
       puts "System information".color(:yellow)
@@ -26,6 +28,7 @@ namespace :gitlab do
       puts "Bundler Version:#{bunder_version || "unknown".color(:red)}"
       puts "Rake Version:\t#{rake_version || "unknown".color(:red)}"
       puts "Redis Version:\t#{redis_version[1] || "unknown".color(:red)}"
+      puts "Git Version:\t#{git_version[1] || "unknown".color(:red)}"
       puts "Sidekiq Version:#{Sidekiq::VERSION}"
 
       # check database adapter

spec/tasks/gitlab/info_rake_spec.rb

+require 'rake_helper'
+
+describe 'gitlab:env:info' do
+  before do
+    Rake.application.rake_require 'tasks/gitlab/info'
+
+    stub_warn_user_is_not_gitlab
+    allow(Gitlab::Popen).to receive(:popen)
+  end
+
+  describe 'git version' do
+    before do
+      allow(Gitlab::Popen).to receive(:popen).with([Gitlab.config.git.bin_path, '--version'])
+        .and_return(git_version)
+    end
+
+    context 'when git installed' do
+      let(:git_version) { 'git version 2.10.0' }
+
+      it 'prints git version' do
+        run_rake_task('gitlab:env:info')
+
+        expect($stdout.string).to match(/Git Version:(.*)2.10.0/)
+      end
+    end
+
+    context 'when git not installed' do
+      let(:git_version) { '' }
+
+      it 'prints unknown' do
+        run_rake_task('gitlab:env:info')
+
+        expect($stdout.string).to match(/Git Version:(.*)unknown/)
+      end
+    end
+  end
+end