Merge branch 'new-branch-button-issue' into 'master'

New branch button on issues

Creates a button which creates a branch for you, referencing the original issue in the branch name. When creating the MR the text `Closes #iid` is appended to the description field.

The button; with styling

![Screenshot_from_2016-02-13_17-28-54](/uploads/9595fbfef88c10a499829beaa3db11c1/Screenshot_from_2016-02-13_17-28-54.png)

Links to the related branches on the issue

![Screenshot_from_2016-02-13_17-31-48](/uploads/ee7a78754eb5e2389f8671771bb59af9/Screenshot_from_2016-02-13_17-31-48.png)

Styled like the MR links

![Screenshot_from_2016-02-13_17-31-53](/uploads/c60130333a650a16f51b014aeb1458c3/Screenshot_from_2016-02-13_17-31-53.png)


Please provide input on the following; the CI repo on the GDK had the following happening with the current way I implemented the matching:

![Screenshot_from_2016-02-14_08-57-19](/uploads/35e7a3687a0fa801aba1ad66305ab2ff/Screenshot_from_2016-02-14_08-57-19.png)

Closes #3886 

cc @DouweM 


See merge request !2808

15 files changed, 238 insertions, 43 deletions

diff --git a/CHANGELOG b/CHANGELOG
index 638a4f1d3fe..342fbb7a6d1 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -4,6 +4,7 @@ v 8.6.0 (unreleased)
   - Bump gitlab_git to 9.0.3 (Stan Hu)
   - Support Golang subpackage fetching (Stan Hu)
   - Bump Capybara gem to 2.6.2 (Stan Hu)
+  - New branch button appears on issues where applicable
   - Contributions to forked projects are included in calendar
   - Improve the formatting for the user page bio (Connor Shea)
   - Removed the default password from the initial admin account created during
diff --git a/app/assets/stylesheets/pages/issues.scss b/app/assets/stylesheets/pages/issues.scss
index 73718ff511a..7ac4bc468d6 100644
--- a/app/assets/stylesheets/pages/issues.scss
+++ b/app/assets/stylesheets/pages/issues.scss
@@ -49,7 +49,7 @@ form.edit-issue {
   margin: 0;
 }
 
-.merge-requests-title {
+.merge-requests-title, .related-branches-title {
   font-size: 16px;
   font-weight: 600;
 }
diff --git a/app/controllers/projects/branches_controller.rb b/app/controllers/projects/branches_controller.rb
index 4db3b3bf23d..43ea717cbd2 100644
--- a/app/controllers/projects/branches_controller.rb
+++ b/app/controllers/projects/branches_controller.rb
@@ -9,7 +9,7 @@ class Projects::BranchesController < Projects::ApplicationController
     @sort = params[:sort] || 'name'
     @branches = @repository.branches_sorted_by(@sort)
     @branches = Kaminari.paginate_array(@branches).page(params[:page]).per(PER_PAGE)
-    
+
     @max_commits = @branches.reduce(0) do |memo, branch|
       diverging_commit_counts = repository.diverging_commit_counts(branch)
       [memo, diverging_commit_counts[:behind], diverging_commit_counts[:ahead]].max
@@ -23,11 +23,15 @@ class Projects::BranchesController < Projects::ApplicationController
   def create
     branch_name = sanitize(strip_tags(params[:branch_name]))
     branch_name = Addressable::URI.unescape(branch_name)
-    ref = sanitize(strip_tags(params[:ref]))
-    ref = Addressable::URI.unescape(ref)
+
     result = CreateBranchService.new(project, current_user).
         execute(branch_name, ref)
 
+    if params[:issue_iid]
+      issue = @project.issues.find_by(iid: params[:issue_iid])
+      SystemNoteService.new_issue_branch(issue, @project, current_user, branch_name) if issue
+    end
+
     if result[:status] == :success
       @branch = result[:branch]
       redirect_to namespace_project_tree_path(@project.namespace, @project,
@@ -49,4 +53,15 @@ class Projects::BranchesController < Projects::ApplicationController
       format.js { render status: status[:return_code] }
     end
   end
+
+  private
+
+  def ref
+    if params[:ref]
+      ref_escaped = sanitize(strip_tags(params[:ref]))
+      Addressable::URI.unescape(ref_escaped)
+    else
+      @project.default_branch
+    end
+  end
 end
diff --git a/app/controllers/projects/issues_controller.rb b/app/controllers/projects/issues_controller.rb
index b0a03ee45cc..aa7a178dcf4 100644
--- a/app/controllers/projects/issues_controller.rb
+++ b/app/controllers/projects/issues_controller.rb
@@ -65,6 +65,7 @@ class Projects::IssuesController < Projects::ApplicationController
     @notes = @issue.notes.nonawards.with_associations.fresh
     @noteable = @issue
     @merge_requests = @issue.referenced_merge_requests(current_user)
+    @related_branches = @issue.related_branches - @merge_requests.map(&:source_branch)
 
     respond_with(@issue)
   end
diff --git a/app/models/issue.rb b/app/models/issue.rb
index 5f58c0508fd..2447f860c5a 100644
--- a/app/models/issue.rb
+++ b/app/models/issue.rb
@@ -87,11 +87,21 @@ class Issue < ActiveRecord::Base
   end
 
   def referenced_merge_requests(current_user = nil)
-    Gitlab::ReferenceExtractor.lazily do
-      [self, *notes].flat_map do |note|
-        note.all_references(current_user).merge_requests
-      end
-    end.sort_by(&:iid)
+    @referenced_merge_requests ||= {}
+    @referenced_merge_requests[current_user] ||= begin
+      Gitlab::ReferenceExtractor.lazily do
+        [self, *notes].flat_map do |note|
+          note.all_references(current_user).merge_requests
+        end
+      end.sort_by(&:iid).uniq
+    end
+  end
+
+  def related_branches
+    return [] if self.project.empty_repo?
+    self.project.repository.branch_names.select do |branch|
+      branch =~ /\A#{iid}-(?!\d+-stable)/i
+    end
   end
 
   # Reset issue events cache
@@ -120,4 +130,15 @@ class Issue < ActiveRecord::Base
       note.all_references(current_user).merge_requests
     end.uniq.select { |mr| mr.open? && mr.closes_issue?(self) }
   end
+
+  def to_branch_name
+    "#{iid}-#{title.parameterize}"
+  end
+
+  def can_be_worked_on?(current_user)
+    !self.closed? &&
+      !self.project.forked? &&
+      self.related_branches.empty? &&
+      self.closed_by_merge_requests(current_user).empty?
+  end
 end
diff --git a/app/services/merge_requests/build_service.rb b/app/services/merge_requests/build_service.rb
index 954746a39a5..fa34753c4fd 100644
--- a/app/services/merge_requests/build_service.rb
+++ b/app/services/merge_requests/build_service.rb
@@ -47,6 +47,21 @@ module MergeRequests
         merge_request.title = merge_request.source_branch.titleize.humanize
       end
 
+      # When your branch name starts with an iid followed by a dash this pattern will
+      # be interpreted as the use wants to close that issue on this project
+      # Pattern example: 112-fix-mep-mep
+      # Will lead to appending `Closes #112` to the description
+      if match = merge_request.source_branch.match(/\A(\d+)-/)
+        iid = match[1]
+        closes_issue = "Closes ##{iid}"
+
+        if merge_request.description.present?
+          merge_request.description << closes_issue.prepend("\n")
+        else
+          merge_request.description = closes_issue
+        end
+      end
+
       merge_request
     end
 
diff --git a/app/services/system_note_service.rb b/app/services/system_note_service.rb
index 58a861ee08e..f09b77c4a57 100644
--- a/app/services/system_note_service.rb
+++ b/app/services/system_note_service.rb
@@ -207,6 +207,18 @@ class SystemNoteService
     create_note(noteable: noteable, project: project, author: author, note: body)
   end
 
+  # Called when a branch is created from the 'new branch' button on a issue
+  # Example note text:
+  #
+  #   "Started branch `201-issue-branch-button`"
+  def self.new_issue_branch(issue, project, author, branch)
+    h = Gitlab::Application.routes.url_helpers
+    link = h.namespace_project_compare_url(project.namespace, project, from: project.default_branch, to: branch)
+
+    body = "Started branch [`#{branch}`](#{link})"
+    create_note(noteable: issue, project: project, author: author, note: body)
+  end
+
   # Called when a Mentionable references a Noteable
   #
   # noteable  - Noteable object being referenced
diff --git a/app/views/projects/issues/_merge_requests.html.haml b/app/views/projects/issues/_merge_requests.html.haml
index d9868ad1f0a..d6b38b327ff 100644
--- a/app/views/projects/issues/_merge_requests.html.haml
+++ b/app/views/projects/issues/_merge_requests.html.haml
@@ -1,4 +1,4 @@
--if @merge_requests.any?
+- if @merge_requests.any?
   %h2.merge-requests-title
     = pluralize(@merge_requests.count, 'Related Merge Request')
   %ul.unstyled-list
diff --git a/app/views/projects/issues/_new_branch.html.haml b/app/views/projects/issues/_new_branch.html.haml
new file mode 100644
index 00000000000..e66e4669d48
--- /dev/null
+++ b/app/views/projects/issues/_new_branch.html.haml
@@ -0,0 +1,5 @@
+- if current_user && can?(current_user, :push_code, @project) && @issue.can_be_worked_on?(current_user)
+  .pull-right
+    = link_to namespace_project_branches_path(@project.namespace, @project, branch_name: @issue.to_branch_name, issue_iid: @issue.iid), method: :post, class: 'btn', title: @issue.to_branch_name do
+      = icon('code-fork')
+      New Branch
diff --git a/app/views/projects/issues/_related_branches.html.haml b/app/views/projects/issues/_related_branches.html.haml
new file mode 100644
index 00000000000..b10cd03515f
--- /dev/null
+++ b/app/views/projects/issues/_related_branches.html.haml
@@ -0,0 +1,15 @@
+- if @related_branches.any?
+  %h2.related-branches-title
+    = pluralize(@related_branches.count, 'Related Branch')
+  %ul.unstyled-list
+    - @related_branches.each do |branch|
+      %li
+        - sha = @project.repository.find_branch(branch).target
+        - ci_commit = @project.ci_commit(sha) if sha
+        - if ci_commit
+          %span.related-branch-ci-status
+            = render_ci_status(ci_commit)
+        %span.related-branch-info
+          %strong
+            = link_to namespace_project_compare_path(@project.namespace, @project, from: @project.default_branch, to: branch), class: "label-branch" do
+              = branch
diff --git a/app/views/projects/issues/show.html.haml b/app/views/projects/issues/show.html.haml
index 0242276cd84..1e8308277cc 100644
--- a/app/views/projects/issues/show.html.haml
+++ b/app/views/projects/issues/show.html.haml
@@ -70,8 +70,10 @@
 
       .merge-requests
         = render 'merge_requests'
+        = render 'related_branches'
 
     .content-block.content-block-small
+      = render 'new_branch'
       = render 'votes/votes_block', votable: @issue
 
     .row
diff --git a/spec/controllers/projects/branches_controller_spec.rb b/spec/controllers/projects/branches_controller_spec.rb
index 8e06d4bdc77..98ae424ed7c 100644
--- a/spec/controllers/projects/branches_controller_spec.rb
+++ b/spec/controllers/projects/branches_controller_spec.rb
@@ -17,49 +17,79 @@ describe Projects::BranchesController do
   describe "POST create" do
     render_views
 
-    before do
-      post :create,
-        namespace_id: project.namespace.to_param,
-        project_id: project.to_param,
-        branch_name: branch,
-        ref: ref
-    end
+    context "on creation of a new branch" do
+      before do
+        post :create,
+          namespace_id: project.namespace.to_param,
+          project_id: project.to_param,
+          branch_name: branch,
+          ref: ref
+      end
 
-    context "valid branch name, valid source" do
-      let(:branch) { "merge_branch" }
-      let(:ref) { "master" }
-      it 'redirects' do
-        expect(subject).
-          to redirect_to("/#{project.path_with_namespace}/tree/merge_branch")
+      context "valid branch name, valid source" do
+        let(:branch) { "merge_branch" }
+        let(:ref) { "master" }
+        it 'redirects' do
+          expect(subject).
+            to redirect_to("/#{project.path_with_namespace}/tree/merge_branch")
+        end
+      end
+
+      context "invalid branch name, valid ref" do
+        let(:branch) { "<script>alert('merge');</script>" }
+        let(:ref) { "master" }
+        it 'redirects' do
+          expect(subject).
+            to redirect_to("/#{project.path_with_namespace}/tree/alert('merge');")
+        end
+      end
+
+      context "valid branch name, invalid ref" do
+        let(:branch) { "merge_branch" }
+        let(:ref) { "<script>alert('ref');</script>" }
+        it { is_expected.to render_template('new') }
+      end
+
+      context "invalid branch name, invalid ref" do
+        let(:branch) { "<script>alert('merge');</script>" }
+        let(:ref) { "<script>alert('ref');</script>" }
+        it { is_expected.to render_template('new') }
+      end
+
+      context "valid branch name with encoded slashes" do
+        let(:branch) { "feature%2Ftest" }
+        let(:ref) { "<script>alert('ref');</script>" }
+        it { is_expected.to render_template('new') }
+        it { project.repository.branch_names.include?('feature/test') }
       end
     end
 
-    context "invalid branch name, valid ref" do
-      let(:branch) { "<script>alert('merge');</script>" }
-      let(:ref) { "master" }
+    describe "created from the new branch button on issues" do
+      let(:branch) { "1-feature-branch" }
+      let!(:issue) { create(:issue, project: project) }
+
+
       it 'redirects' do
+        post :create,
+          namespace_id: project.namespace.to_param,
+          project_id: project.to_param,
+          branch_name: branch,
+          issue_iid: issue.iid
+
         expect(subject).
-          to redirect_to("/#{project.path_with_namespace}/tree/alert('merge');")
+          to redirect_to("/#{project.path_with_namespace}/tree/1-feature-branch")
       end
-    end
 
-    context "valid branch name, invalid ref" do
-      let(:branch) { "merge_branch" }
-      let(:ref) { "<script>alert('ref');</script>" }
-      it { is_expected.to render_template('new') }
-    end
+      it 'posts a system note' do
+        expect(SystemNoteService).to receive(:new_issue_branch).with(issue, project, user, "1-feature-branch")
 
-    context "invalid branch name, invalid ref" do
-      let(:branch) { "<script>alert('merge');</script>" }
-      let(:ref) { "<script>alert('ref');</script>" }
-      it { is_expected.to render_template('new') }
-    end
+        post :create,
+          namespace_id: project.namespace.to_param,
+          project_id: project.to_param,
+          branch_name: branch,
+          issue_iid: issue.iid
+      end
 
-    context "valid branch name with encoded slashes" do
-      let(:branch) { "feature%2Ftest" }
-      let(:ref) { "<script>alert('ref');</script>" }
-      it { is_expected.to render_template('new') }
-      it { project.repository.branch_names.include?('feature/test')}
     end
   end
 
diff --git a/spec/features/issues/new_branch_button_spec.rb b/spec/features/issues/new_branch_button_spec.rb
new file mode 100644
index 00000000000..1f3bd915f48
--- /dev/null
+++ b/spec/features/issues/new_branch_button_spec.rb
@@ -0,0 +1,49 @@
+require 'rails_helper'
+
+feature 'Start new branch from an issue', feature: true do
+  let!(:project)   { create(:project) }
+  let!(:issue)     { create(:issue, project: project) }
+  let!(:user)      { create(:user)}
+
+  context "for team members" do
+    before do
+      project.team << [user, :master]
+      login_as(user)
+    end
+
+    it 'shown the new branch button', js: false do
+      visit namespace_project_issue_path(project.namespace, project, issue)
+
+      expect(page).to have_link "New Branch"
+    end
+
+    context "when there is a referenced merge request" do
+      let(:note) do
+        create(:note, :on_issue, :system, project: project,
+                                          note: "mentioned in !#{referenced_mr.iid}")
+      end
+      let(:referenced_mr) do
+        create(:merge_request, :simple, source_project: project, target_project: project,
+                                        description: "Fixes ##{issue.iid}")
+      end
+
+      before do
+        issue.notes << note
+
+        visit namespace_project_issue_path(project.namespace, project, issue)
+      end
+
+      it "hides the new branch button", js: true do
+        expect(page).not_to have_link "New Branch"
+        expect(page).to have_content /1 Related Merge Request/
+      end
+    end
+  end
+
+  context "for visiters" do
+    it 'no button is shown', js: false do
+      visit namespace_project_issue_path(project.namespace, project, issue)
+      expect(page).not_to have_link "New Branch"
+    end
+  end
+end
diff --git a/spec/models/issue_spec.rb b/spec/models/issue_spec.rb
index 7f44ca2f7db..2ccdec1eeff 100644
--- a/spec/models/issue_spec.rb
+++ b/spec/models/issue_spec.rb
@@ -130,6 +130,15 @@ describe Issue, models: true do
     end
   end
 
+  describe '#related_branches' do
+    it "should " do
+      allow(subject.project.repository).to receive(:branch_names).
+                                    and_return(["mpempe", "#{subject.iid}mepmep", subject.to_branch_name])
+
+      expect(subject.related_branches).to eq [subject.to_branch_name]
+    end
+  end
+
   it_behaves_like 'an editable mentionable' do
     subject { create(:issue) }
 
@@ -140,4 +149,12 @@ describe Issue, models: true do
   it_behaves_like 'a Taskable' do
     let(:subject) { create :issue }
   end
+
+  describe "#to_branch_name" do
+    let(:issue) { build(:issue, title: 'a' * 30) }
+
+    it "starts with the issue iid" do
+      expect(issue.to_branch_name).to match /\A#{issue.iid}-a+\z/
+    end
+  end
 end
diff --git a/spec/services/system_note_service_spec.rb b/spec/services/system_note_service_spec.rb
index 5dcc39f5fdc..8e6292014d4 100644
--- a/spec/services/system_note_service_spec.rb
+++ b/spec/services/system_note_service_spec.rb
@@ -280,6 +280,18 @@ describe SystemNoteService, services: true do
     end
   end
 
+  describe '.new_issue_branch' do
+    subject { described_class.new_issue_branch(noteable, project, author, "1-mepmep") }
+
+    it_behaves_like 'a system note'
+
+    context 'when a branch is created from the new branch button' do
+      it 'sets the note text' do
+        expect(subject.note).to match /\AStarted branch [`1-mepmep`]/
+      end
+    end
+  end
+
   describe '.cross_reference' do
     subject { described_class.cross_reference(noteable, mentioner, author) }