Delegate a single discussion to a new issue

Delegate a discussion in a merge request into a new issue.
The discussion wil be marked as resolved and a system note will be
added linking to the newly created issue.

13 files changed, 160 insertions, 29 deletions

diff --git a/app/assets/javascripts/diff_notes/components/new_issue_for_discussion.js.es6 b/app/assets/javascripts/diff_notes/components/new_issue_for_discussion.js.es6
new file mode 100644
index 00000000000..e86bef47172
--- /dev/null
+++ b/app/assets/javascripts/diff_notes/components/new_issue_for_discussion.js.es6
@@ -0,0 +1,29 @@
+/* global Vue */
+/* global CommentsStore */
+
+(() => {
+  const NewIssueForDiscussion = Vue.extend({
+    props: {
+      discussionId: {
+        type: String,
+        required: true,
+      },
+    },
+    data() {
+      return {
+        discussions: CommentsStore.state,
+      };
+    },
+    computed: {
+      discussion() {
+        return this.discussions[this.discussionId];
+      },
+      showButton() {
+        if (this.discussion) return !this.discussion.isResolved();
+        return false;
+      },
+    },
+  });
+
+  Vue.component('new-issue-for-discussion-btn', NewIssueForDiscussion);
+})();
diff --git a/app/assets/javascripts/diff_notes/diff_notes_bundle.js b/app/assets/javascripts/diff_notes/diff_notes_bundle.js
index 7d8316dfd63..4f6b86a917c 100644
--- a/app/assets/javascripts/diff_notes/diff_notes_bundle.js
+++ b/app/assets/javascripts/diff_notes/diff_notes_bundle.js
@@ -14,10 +14,11 @@ require('./components/resolve_btn');
 require('./components/resolve_count');
 require('./components/resolve_discussion_btn');
 require('./components/diff_note_avatars');
+require('./components/new_issue_for_discussion');
 
 $(() => {
   const projectPath = document.querySelector('.merge-request').dataset.projectPath;
-  const COMPONENT_SELECTOR = 'resolve-btn, resolve-discussion-btn, jump-to-discussion, comment-and-resolve-btn';
+  const COMPONENT_SELECTOR = 'resolve-btn, resolve-discussion-btn, jump-to-discussion, comment-and-resolve-btn, new-issue-for-discussion-btn';
 
   window.gl = window.gl || {};
   window.gl.diffNoteApps = {};
diff --git a/app/assets/stylesheets/pages/note_form.scss b/app/assets/stylesheets/pages/note_form.scss
index f984b469609..c2156a5ac69 100644
--- a/app/assets/stylesheets/pages/note_form.scss
+++ b/app/assets/stylesheets/pages/note_form.scss
@@ -178,8 +178,25 @@
       padding-right: 5px;
     }
 
-    &:last-child {
-      padding-left: 5px;
+  }
+
+  .discussion-actions {
+    display: table;
+
+    .new-issue-for-discussion path {
+      fill: $gray-darkest;
+    }
+
+    .btn-group {
+      display: table-cell;
+
+      &:first-child {
+        padding-right: 0;
+      }
+
+      &:first-child:not(:last-child) > div {
+        border-right: 0;
+      }
     }
   }
 
diff --git a/app/controllers/projects/issues_controller.rb b/app/controllers/projects/issues_controller.rb
index 1151555b8fa..d7eb73d7ff5 100644
--- a/app/controllers/projects/issues_controller.rb
+++ b/app/controllers/projects/issues_controller.rb
@@ -64,7 +64,12 @@ class Projects::IssuesController < Projects::ApplicationController
     params[:issue] ||= ActionController::Parameters.new(
       assignee_id: ""
     )
-    build_params = issue_params.merge(merge_request_for_resolving_discussions: merge_request_for_resolving_discussions)
+
+    build_params = issue_params.merge(
+      merge_request_for_resolving_discussions: merge_request_for_resolving_discussions,
+      discussion_to_resolve: discussion_to_resolve
+    )
+
     @issue = @noteable = Issues::BuildService.new(project, current_user, build_params).execute
 
     respond_with(@issue)
@@ -94,10 +99,12 @@ class Projects::IssuesController < Projects::ApplicationController
   end
 
   def create
-    create_params = issue_params
-      .merge(merge_request_for_resolving_discussions: merge_request_for_resolving_discussions)
-      .merge(spammable_params)
-
+    create_params = issue_params.
+                      merge(
+                        merge_request_for_resolving_discussions: merge_request_for_resolving_discussions,
+                        discussion_to_resolve: discussion_to_resolve
+                      ).
+                      merge(spammable_params)
     @issue = Issues::CreateService.new(project, current_user, create_params).execute
 
     respond_to do |format|
@@ -193,6 +200,13 @@ class Projects::IssuesController < Projects::ApplicationController
                                                    find_by(iid: merge_request_iid)
   end
 
+  def discussion_to_resolve
+    return unless discussion_id = params[:discussion_to_resolve]
+
+    @discussion_to_resolve ||= NotesFinder.new(project, current_user, discussion_id: discussion_id).
+                                 first_discussion
+  end
+
   def authorize_read_issue!
     return render_404 unless can?(current_user, :read_issue, @issue)
   end
diff --git a/app/finders/notes_finder.rb b/app/finders/notes_finder.rb
index 6630c6384f2..c93e6b05a67 100644
--- a/app/finders/notes_finder.rb
+++ b/app/finders/notes_finder.rb
@@ -11,6 +11,7 @@ class NotesFinder
   #     target_type: string
   #     target_id: integer
   #     last_fetched_at: time
+  #     discussion_id: string
   #     search: string
   #
   def initialize(project, current_user, params = {})
@@ -22,9 +23,14 @@ class NotesFinder
 
   def execute
     @notes = since_fetch_at(@params[:last_fetched_at]) if @params[:last_fetched_at]
+    @notes = for_discussion(@params[:discussion_id]) if @params[:discussion_id]
     @notes
   end
 
+  def first_discussion
+    execute.discussions.first
+  end
+
   private
 
   def init_collection
@@ -100,4 +106,8 @@ class NotesFinder
 
     @notes.where('updated_at > ?', last_fetched_at - FETCH_OVERLAP).fresh
   end
+
+  def for_discussion(discussion_id)
+    @notes.where(Note.arel_table[:discussion_id].eq(discussion_id))
+  end
 end
diff --git a/app/services/discussions/resolve_service.rb b/app/services/discussions/resolve_service.rb
index 0437195f588..4a803b47bba 100644
--- a/app/services/discussions/resolve_service.rb
+++ b/app/services/discussions/resolve_service.rb
@@ -9,7 +9,13 @@ module Discussions
 
       discussion.resolve!(current_user)
 
-      MergeRequests::ResolvedDiscussionNotificationService.new(project, current_user).execute(merge_request)
+      notify_discussion_resolved(discussion)
+    end
+
+    def notify_discussion_resolved(discussion)
+      noteable = merge_request || discussion.noteable
+
+      MergeRequests::ResolvedDiscussionNotificationService.new(project, current_user).execute(noteable)
       SystemNoteService.discussion_continued_in_issue(discussion, project, current_user, follow_up_issue) if follow_up_issue
     end
 
diff --git a/app/services/issues/base_service.rb b/app/services/issues/base_service.rb
index 35af867a098..3aa842eb9a8 100644
--- a/app/services/issues/base_service.rb
+++ b/app/services/issues/base_service.rb
@@ -1,11 +1,12 @@
 module Issues
   class BaseService < ::IssuableBaseService
-    attr_reader :merge_request_for_resolving_discussions
+    attr_reader :merge_request_for_resolving_discussions, :discussion_to_resolve
 
     def initialize(*args)
       super
 
       @merge_request_for_resolving_discussions ||= params.delete(:merge_request_for_resolving_discussions)
+      @discussion_to_resolve ||= params.delete(:discussion_to_resolve)
     end
 
     def hook_data(issue, action)
@@ -15,6 +16,28 @@ module Issues
       issue_data
     end
 
+    def merge_request_for_resolving_discussions
+      @merge_request_for_resolving_discussions ||= discussion_to_resolve.try(:noteable)
+    end
+
+    def for_all_discussions_in_a_merge_request?
+      discussion_to_resolve.nil? && merge_request_for_resolving_discussions
+    end
+
+    def for_single_discussion?
+      discussion_to_resolve && discussion_to_resolve.noteable == merge_request_for_resolving_discussions
+    end
+
+    def discussions_to_resolve
+      @discussions_to_resolve ||= if for_all_discussions_in_a_merge_request?
+                                    merge_request_for_resolving_discussions.resolvable_discussions
+                                  elsif for_single_discussion?
+                                    Array(discussion_to_resolve)
+                                  else
+                                    []
+                                  end
+    end
+
     private
 
     def execute_hooks(issue, action = 'open')
diff --git a/app/services/issues/build_service.rb b/app/services/issues/build_service.rb
index 7cd927d8005..1bcc5abd3f2 100644
--- a/app/services/issues/build_service.rb
+++ b/app/services/issues/build_service.rb
@@ -4,32 +4,35 @@ module Issues
       @issue = project.issues.new(issue_params)
     end
 
-    def issue_params_with_info_from_merge_request
+    def issue_params_with_info_from_discussions
       return {} unless merge_request_for_resolving_discussions
 
-      { title: title_from_merge_request, description: description_from_merge_request }
+      { title: title_for_merge_request, description: description_for_discussions }
     end
 
-    def title_from_merge_request
+    def title_for_merge_request
       "Follow-up from \"#{merge_request_for_resolving_discussions.title}\""
     end
 
-    def description_from_merge_request
-      if merge_request_for_resolving_discussions.resolvable_discussions.empty?
+    def description_for_discussions
+      if discussions_to_resolve.empty?
         return "There are no unresolved discussions. "\
                "Review the conversation in #{merge_request_for_resolving_discussions.to_reference}"
       end
 
-      description = "The following discussions from #{merge_request_for_resolving_discussions.to_reference} should be addressed:"
+      description = "The following #{'discussion'.pluralize(discussions_to_resolve.size)} "\
+                    "from #{merge_request_for_resolving_discussions.to_reference} "\
+                    "should be addressed:"
+
       [description, *items_for_discussions].join("\n\n")
     end
 
     def items_for_discussions
-      merge_request_for_resolving_discussions.resolvable_discussions.map { |discussion| item_for_discussion(discussion) }
+      discussions_to_resolve.map { |discussion| item_for_discussion(discussion) }
     end
 
     def item_for_discussion(discussion)
-      first_note = discussion.first_note_to_resolve
+      first_note = discussion.first_note_to_resolve || discussion.first_note
       other_note_count = discussion.notes.size - 1
       creation_time = first_note.created_at.to_s(:medium)
       note_url = Gitlab::UrlBuilder.build(first_note)
@@ -44,7 +47,7 @@ module Issues
     end
 
     def issue_params
-      @issue_params ||= issue_params_with_info_from_merge_request.merge(whitelisted_issue_params)
+      @issue_params ||= issue_params_with_info_from_discussions.merge(whitelisted_issue_params)
     end
 
     def whitelisted_issue_params
diff --git a/app/services/issues/create_service.rb b/app/services/issues/create_service.rb
index 85b6eb3fe3d..d2cc70ed0dc 100644
--- a/app/services/issues/create_service.rb
+++ b/app/services/issues/create_service.rb
@@ -5,7 +5,11 @@ module Issues
     def execute
       filter_spam_check_params
 
-      issue_attributes = params.merge(merge_request_for_resolving_discussions: merge_request_for_resolving_discussions)
+      issue_attributes = params.merge(
+        merge_request_for_resolving_discussions: merge_request_for_resolving_discussions,
+        discussion_to_resolve: discussion_to_resolve
+      )
+
       @issue = BuildService.new(project, current_user, issue_attributes).execute
 
       create(@issue)
@@ -21,17 +25,16 @@ module Issues
       notification_service.new_issue(issuable, current_user)
       todo_service.new_issue(issuable, current_user)
       user_agent_detail_service.create
-
-      if merge_request_for_resolving_discussions.try(:discussions_can_be_resolved_by?, current_user)
-        resolve_discussions_in_merge_request(issuable)
-      end
+      resolve_discussions_with_issue(issuable)
     end
 
-    def resolve_discussions_in_merge_request(issue)
+    def resolve_discussions_with_issue(issue)
+      return if discussions_to_resolve.empty?
+
       Discussions::ResolveService.new(project, current_user,
                                       merge_request: merge_request_for_resolving_discussions,
                                       follow_up_issue: issue).
-          execute(merge_request_for_resolving_discussions.resolvable_discussions)
+          execute(discussions_to_resolve)
     end
 
     private
diff --git a/app/views/discussions/_new_issue_for_discussion.html.haml b/app/views/discussions/_new_issue_for_discussion.html.haml
new file mode 100644
index 00000000000..de28ded9820
--- /dev/null
+++ b/app/views/discussions/_new_issue_for_discussion.html.haml
@@ -0,0 +1,8 @@
+- if discussion.can_resolve?(current_user) && can?(current_user, :create_issue, @project)
+  %new-issue-for-discussion-btn{ ":discussion-id" => "'#{discussion.id}'",
+                                 "inline-template" => true }
+    .btn-group{ role: "group", "v-if" => "showButton" }
+      .btn.btn-default.discussion-create-issue-btn.has-tooltip{ title: "Resolve this discussion in a new issue",
+                                                               "aria-label" => "Resolve this discussion in a new issue",
+                                                               "data-container" => "body" }
+        = link_to custom_icon('icon_mr_issue'), new_namespace_project_issue_path(@project.namespace, @project, discussion_to_resolve: discussion.id), title: "Resolve this discussion in a new issue", class: 'new-issue-for-discussion'
diff --git a/app/views/discussions/_notes.html.haml b/app/views/discussions/_notes.html.haml
index dfdbdf1f969..4a1e93cec3a 100644
--- a/app/views/discussions/_notes.html.haml
+++ b/app/views/discussions/_notes.html.haml
@@ -11,6 +11,8 @@
           = link_to_reply_discussion(discussion, line_type)
         = render "discussions/resolve_all", discussion: discussion
         - if discussion.for_merge_request?
-          = render "discussions/jump_to_next", discussion: discussion
+          .btn-group.discussion-actions
+            = render "discussions/new_issue_for_discussion", discussion: discussion
+            = render "discussions/jump_to_next", discussion: discussion
     - else
       = link_to_reply_discussion(discussion)
diff --git a/app/views/shared/icons/_icon_mr_issue.svg b/app/views/shared/icons/_icon_mr_issue.svg
new file mode 100644
index 00000000000..ae219a3ded2
--- /dev/null
+++ b/app/views/shared/icons/_icon_mr_issue.svg
@@ -0,0 +1 @@
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 16 16"><g fill-rule="evenodd"><path d="m8.411 1.012c-.136-.008-.273-.012-.411-.012-3.866 0-7 3.134-7 7 0 3.866 3.134 7 7 7 3.866 0 7-3.134 7-7 0-.138-.004-.275-.012-.411-.464.201-.964.334-1.488.386 0 .008 0 .016 0 .025 0 3.038-2.462 5.5-5.5 5.5-3.038 0-5.5-2.462-5.5-5.5 0-3.038 2.462-5.5 5.5-5.5.008 0 .016 0 .025 0 .052-.524.185-1.024.386-1.488"/><path d="m12 2h-1.01c-.54 0-.991.448-.991 1 0 .556.444 1 .991 1h1.01v1.01c0 .54.448.991 1 .991.556 0 1-.444 1-.991v-1.01h1.01c.54 0 .991-.448.991-1 0-.556-.444-1-.991-1h-1.01v-1.01c0-.54-.448-.991-1-.991-.556 0-1 .444-1 .991v1.01m-5 4.01c0-.557.444-1.01 1-1.01.552 0 1 .443 1 1.01v1.981c0 .557-.444 1.01-1 1.01-.552 0-1-.443-1-1.01v-1.981m1 5.991c.552 0 1-.448 1-1 0-.552-.448-1-1-1-.552 0-1 .448-1 1 0 .552.448 1 1 1"/></g></svg>
\ No newline at end of file
diff --git a/app/views/shared/issuable/_form.html.haml b/app/views/shared/issuable/_form.html.haml
index 70470c83c51..e93fe0f6cb5 100644
--- a/app/views/shared/issuable/_form.html.haml
+++ b/app/views/shared/issuable/_form.html.haml
@@ -48,18 +48,32 @@
 - if @merge_request_for_resolving_discussions
   .form-group
     .col-sm-10.col-sm-offset-2
+      = icon('exclamation-triangle')
       - if @merge_request_for_resolving_discussions.discussions_can_be_resolved_by?(current_user)
-        = icon('exclamation-triangle')
         Creating this issue will mark all discussions in
         = link_to @merge_request_for_resolving_discussions.to_reference, merge_request_path(@merge_request_for_resolving_discussions)
         as resolved.
         = hidden_field_tag 'merge_request_for_resolving_discussions', @merge_request_for_resolving_discussions.iid
       - else
-        = icon('exclamation-triangle')
         You can't automatically mark all discussions in
         = link_to @merge_request_for_resolving_discussions.to_reference, merge_request_path(@merge_request_for_resolving_discussions)
         as resolved. Ask someone with sufficient rights to resolve the them.
 
+- if @discussion_to_resolve
+  .form-group
+    .col-sm-10.col-sm-offset-2
+      = icon('exclamation-triangle')
+      - if @discussion_to_resolve.can_resolve?(current_user)
+        Creating this issue will mark the discussion at
+        = link_to @discussion_to_resolve.noteable.to_reference, Gitlab::UrlBuilder.build(@discussion_to_resolve.first_note)
+        as resolved.
+        = hidden_field_tag 'discussion_to_resolve', @discussion_to_resolve.id
+      - else
+        You can't automatically mark the discussion at
+        = link_to @discussion_to_resolve.noteable.to_reference, Gitlab::UrlBuilder.build(@discussion_to_resolve.first_note)
+        as resolved. Ask someone with sufficient rights to resolve it.
+
+
 - is_footer = !(issuable.is_a?(MergeRequest) && issuable.new_record?)
 .row-content-block{ class: (is_footer ? "footer-block" : "middle-block") }
   .pull-right