diff --git a/CHANGELOG b/CHANGELOG
index cd936e08a8a..eab4ff4e6ad 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -81,6 +81,7 @@ v 7.9.3
   - Warn when gitlab-shell version doesn't match requirement.
   - Skip email confirmation when set by admin or via LDAP.
 
+  - Only allow users to reference groups, projects, issues, MRs, commits they have access to.
 
 v 7.9.2
   - Contains no changes
diff --git a/Gemfile b/Gemfile
index a3720ce17f8..465e90e71a3 100644
--- a/Gemfile
+++ b/Gemfile
@@ -208,7 +208,6 @@ group :development do
   gem "letter_opener"
   gem 'quiet_assets', '~> 1.0.1'
   gem 'rack-mini-profiler', require: false
-  gem "byebug"
 
   # Better errors handler
   gem 'better_errors'
@@ -257,6 +256,8 @@ group :development, :test do
   gem "spring", '~> 1.3.1'
   gem "spring-commands-rspec", '1.0.4'
   gem "spring-commands-spinach", '1.0.0'
+  
+  gem "byebug"
 end
 
 group :test do
diff --git a/app/helpers/commits_helper.rb b/app/helpers/commits_helper.rb
index 5aae697e2f0..d13d80be293 100644
--- a/app/helpers/commits_helper.rb
+++ b/app/helpers/commits_helper.rb
@@ -134,12 +134,13 @@ module CommitsHelper
   #  avatar: true will prepend the avatar image
   #  size:   size of the avatar image in px
   def commit_person_link(commit, options = {})
+    user = commit.send(options[:source])
+    
     source_name = clean(commit.send "#{options[:source]}_name".to_sym)
     source_email = clean(commit.send "#{options[:source]}_email".to_sym)
 
-    user = User.find_for_commit(source_email, source_name)
-    person_name = user.nil? ? source_name : user.name
-    person_email = user.nil? ? source_email : user.email
+    person_name = user.try(:name) || source_name
+    person_email = user.try(:email) || source_email
 
     text =
       if options[:avatar]
diff --git a/app/mailers/emails/groups.rb b/app/mailers/emails/groups.rb
index 26f43bf955e..626eb593d51 100644
--- a/app/mailers/emails/groups.rb
+++ b/app/mailers/emails/groups.rb
@@ -4,6 +4,7 @@ module Emails
       @group_member = GroupMember.find(group_member_id)
       @group = @group_member.group
       @target_url = group_url(@group)
+      @current_user = @group_member.user
       mail(to: @group_member.user.email,
            subject: subject("Access to group was granted"))
     end
diff --git a/app/mailers/emails/profile.rb b/app/mailers/emails/profile.rb
index ab5b0765352..3a83b083109 100644
--- a/app/mailers/emails/profile.rb
+++ b/app/mailers/emails/profile.rb
@@ -1,7 +1,7 @@
 module Emails
   module Profile
     def new_user_email(user_id, token = nil)
-      @user = User.find(user_id)
+      @current_user = @user = User.find(user_id)
       @target_url = user_url(@user)
       @token = token
       mail(to: @user.notification_email, subject: subject("Account was created for you"))
@@ -9,13 +9,13 @@ module Emails
 
     def new_email_email(email_id)
       @email = Email.find(email_id)
-      @user = @email.user
+      @current_user = @user = @email.user
       mail(to: @user.notification_email, subject: subject("Email was added to your account"))
     end
 
     def new_ssh_key_email(key_id)
       @key = Key.find(key_id)
-      @user = @key.user
+      @current_user = @user = @key.user
       @target_url = user_url(@user)
       mail(to: @user.notification_email, subject: subject("SSH key was added to your account"))
     end
diff --git a/app/mailers/emails/projects.rb b/app/mailers/emails/projects.rb
index 3cd812825e2..20a863c3742 100644
--- a/app/mailers/emails/projects.rb
+++ b/app/mailers/emails/projects.rb
@@ -4,12 +4,13 @@ module Emails
       @project_member = ProjectMember.find user_project_id
       @project = @project_member.project
       @target_url = namespace_project_url(@project.namespace, @project)
+      @current_user = @project_member.user
       mail(to: @project_member.user.email,
            subject: subject("Access to project was granted"))
     end
 
     def project_was_moved_email(project_id, user_id)
-      @user = User.find user_id
+      @current_user = @user = User.find user_id
       @project = Project.find project_id
       @target_url = namespace_project_url(@project.namespace, @project)
       mail(to: @user.notification_email,
@@ -28,7 +29,7 @@ module Emails
       end
 
       @project = Project.find(project_id)
-      @author  = User.find(author_id)
+      @current_user = @author  = User.find(author_id)
       @reverse_compare = reverse_compare
       @compare = compare
       @ref_name  = Gitlab::Git.ref_name(ref)
diff --git a/app/mailers/notify.rb b/app/mailers/notify.rb
index 0c186ab5866..7c8b37029d1 100644
--- a/app/mailers/notify.rb
+++ b/app/mailers/notify.rb
@@ -13,6 +13,9 @@ class Notify < ActionMailer::Base
   add_template_helper MergeRequestsHelper
   add_template_helper EmailsHelper
 
+  attr_accessor :current_user
+  helper_method :current_user, :can?
+
   default_url_options[:host]     = Gitlab.config.gitlab.host
   default_url_options[:protocol] = Gitlab.config.gitlab.protocol
   default_url_options[:port]     = Gitlab.config.gitlab.port unless Gitlab.config.gitlab_on_standard_port?
@@ -79,9 +82,8 @@ class Notify < ActionMailer::Base
   #
   # Returns a String containing the User's email address.
   def recipient(recipient_id)
-    if recipient = User.find(recipient_id)
-      recipient.notification_email
-    end
+    @current_user = User.find(recipient_id)
+    @current_user.notification_email
   end
 
   # Set the References header field
@@ -154,4 +156,8 @@ class Notify < ActionMailer::Base
 
     mail(headers, &block)
   end
+
+  def can?
+    Ability.abilities.allowed?(user, action, subject)
+  end
 end
diff --git a/app/models/commit.rb b/app/models/commit.rb
index e0461809e10..7a0ad137650 100644
--- a/app/models/commit.rb
+++ b/app/models/commit.rb
@@ -117,8 +117,8 @@ class Commit
 
   # Discover issues should be closed when this commit is pushed to a project's
   # default branch.
-  def closes_issues(project)
-    Gitlab::ClosingIssueExtractor.closed_by_message_in_project(safe_message, project)
+  def closes_issues(project, current_user = self.committer)
+    Gitlab::ClosingIssueExtractor.new(project, current_user).closed_by_message(safe_message)
   end
 
   # Mentionable override.
@@ -126,6 +126,14 @@ class Commit
     "commit #{id}"
   end
 
+  def author
+    User.find_for_commit(author_email, author_name)
+  end
+
+  def committer
+    User.find_for_commit(committer_email, committer_name)
+  end
+
   def method_missing(m, *args, &block)
     @raw.send(m, *args, &block)
   end
diff --git a/app/models/concerns/issuable.rb b/app/models/concerns/issuable.rb
index 88ac83744df..478134dff68 100644
--- a/app/models/concerns/issuable.rb
+++ b/app/models/concerns/issuable.rb
@@ -118,16 +118,16 @@ module Issuable
   end
 
   # Return all users participating on the discussion
-  def participants
+  def participants(current_user = self.author)
     users = []
     users << author
     users << assignee if is_assigned?
     mentions = []
-    mentions << self.mentioned_users
+    mentions << self.mentioned_users(current_user)
 
     notes.each do |note|
       users << note.author
-      mentions << note.mentioned_users
+      mentions << note.mentioned_users(current_user)
     end
 
     users.concat(mentions.reduce([], :|)).uniq
@@ -140,7 +140,7 @@ module Issuable
       return subscription.subscribed
     end
 
-    participants.include?(user)
+    participants(user).include?(user)
   end
 
   def toggle_subscription(user)
diff --git a/app/models/concerns/mentionable.rb b/app/models/concerns/mentionable.rb
index d96e07034ec..b7882a2bb16 100644
--- a/app/models/concerns/mentionable.rb
+++ b/app/models/concerns/mentionable.rb
@@ -42,35 +42,22 @@ module Mentionable
     Note.cross_reference_exists?(target, local_reference)
   end
 
-  def mentioned_users
-    users = []
-    return users if mentionable_text.blank?
-    has_project = self.respond_to? :project
-    matches = mentionable_text.scan(/@[a-zA-Z][a-zA-Z0-9_\-\.]*/)
-    matches.each do |match|
-      identifier = match.delete "@"
-      if identifier == "all"
-        users.push(*project.team.members.flatten)
-      elsif namespace = Namespace.find_by(path: identifier)
-        if namespace.is_a?(Group)
-          users.push(*namespace.users)
-        else
-          users << namespace.owner
-        end
-      end
-    end
-    users.uniq
+  def mentioned_users(current_user = nil)
+    return [] if mentionable_text.blank?
+
+    ext = Gitlab::ReferenceExtractor.new(self.project, current_user)
+    ext.analyze(mentionable_text)
+    ext.users.uniq
   end
 
   # Extract GFM references to other Mentionables from this Mentionable. Always excludes its #local_reference.
-  def references(p = project, text = mentionable_text)
+  def references(p = project, current_user = self.author, text = mentionable_text)
     return [] if text.blank?
-    ext = Gitlab::ReferenceExtractor.new
-    ext.analyze(text, p)
 
-    (ext.issues_for(p)  +
-     ext.merge_requests_for(p) +
-     ext.commits_for(p)).uniq - [local_reference]
+    ext = Gitlab::ReferenceExtractor.new(p, current_user)
+    ext.analyze(text)
+
+    (ext.issues + ext.merge_requests + ext.commits).uniq - [local_reference]
   end
 
   # Create a cross-reference Note for each GFM reference to another Mentionable found in +mentionable_text+.
@@ -96,7 +83,7 @@ module Mentionable
     # Only proceed if the saved changes actually include a chance to an attr_mentionable field.
     return unless mentionable_changed
 
-    preexisting = references(p, original)
+    preexisting = references(p, self.author, original)
     create_cross_references!(p, a, preexisting)
   end
 end
diff --git a/app/models/merge_request.rb b/app/models/merge_request.rb
index 5634f9a686e..35cb920d8bc 100644
--- a/app/models/merge_request.rb
+++ b/app/models/merge_request.rb
@@ -257,11 +257,11 @@ class MergeRequest < ActiveRecord::Base
   end
 
   # Return the set of issues that will be closed if this merge request is accepted.
-  def closes_issues
+  def closes_issues(current_user = self.author)
     if target_branch == project.default_branch
-      issues = commits.flat_map { |c| c.closes_issues(project) }
-      issues.push(*Gitlab::ClosingIssueExtractor.
-                  closed_by_message_in_project(description, project))
+      issues = commits.flat_map { |c| c.closes_issues(project, current_user) }
+      issues.push(*Gitlab::ClosingIssueExtractor.new(project, current_user).
+                  closed_by_message(description))
       issues.uniq.sort_by(&:id)
     else
       []
diff --git a/app/services/git_push_service.rb b/app/services/git_push_service.rb
index 1f0b29dff5e..31e0167d247 100644
--- a/app/services/git_push_service.rb
+++ b/app/services/git_push_service.rb
@@ -70,7 +70,7 @@ class GitPushService
       # Close issues if these commits were pushed to the project's default branch and the commit message matches the
       # closing regex. Exclude any mentioned Issues from cross-referencing even if the commits are being pushed to
       # a different branch.
-      issues_to_close = commit.closes_issues(project)
+      issues_to_close = commit.closes_issues(project, user)
 
       # Load commit author only if needed.
       # For push with 1k commits it prevents 900+ requests in database
@@ -87,7 +87,7 @@ class GitPushService
       # Create cross-reference notes for any other references. Omit any issues that were referenced in an
       # issue-closing phrase, or have already been mentioned from this commit (probably from this commit
       # being pushed to a different branch).
-      refs = commit.references(project) - issues_to_close
+      refs = commit.references(project, user) - issues_to_close
       refs.reject! { |r| commit.has_mentioned?(r) }
 
       if refs.present?
@@ -127,6 +127,6 @@ class GitPushService
   end
 
   def commit_user(commit)
-    User.find_for_commit(commit.author_email, commit.author_name) || user
+    commit.author || user
   end
 end
diff --git a/app/services/notification_service.rb b/app/services/notification_service.rb
index cc5853144c5..42547f6f481 100644
--- a/app/services/notification_service.rb
+++ b/app/services/notification_service.rb
@@ -123,32 +123,29 @@ class NotificationService
     return true if note.note.start_with?('Status changed to closed')
     return true if note.cross_reference? && note.system == true
 
-    opts = { noteable_type: note.noteable_type, project_id: note.project_id }
-
     target = note.noteable
 
-    if target.respond_to?(:participants)
-      recipients = target.participants
-    else
-      recipients = note.mentioned_users
-    end
+    recipients = []
 
     if note.commit_id.present?
-      opts.merge!(commit_id: note.commit_id)
       recipients << note.commit_author
-    else
-      opts.merge!(noteable_id: note.noteable_id)
     end
 
     # Get users who left comment in thread
-    recipients = recipients.concat(User.where(id: Note.where(opts).pluck(:author_id)))
+    recipients = recipients.concat(noteable_commenters(note))
 
     # Merge project watchers
     recipients = recipients.concat(project_watchers(note.project)).compact.uniq
 
-    # Reject mention users unless mentioned in comment
-    recipients = reject_mention_users(recipients - note.mentioned_users, note.project)
-    recipients = recipients + note.mentioned_users
+    # Reject users with Mention notification level
+    recipients = reject_mention_users(recipients, note.project)
+
+    # Add explicitly mentioned users
+    if target.respond_to?(:participants)
+      recipients = recipients.concat(target.participants)
+    else
+      recipients = recipients.concat(note.mentioned_users)
+    end
 
     # Reject mutes users
     recipients = reject_muted_users(recipients, note.project)
@@ -195,6 +192,18 @@ class NotificationService
 
   protected
 
+  def noteable_commenters(note)
+    opts = { noteable_type: note.noteable_type, project_id: note.project_id }
+
+    if note.commit_id.present?
+      opts.merge!(commit_id: note.commit_id)
+    else
+      opts.merge!(noteable_id: note.noteable_id)
+    end
+
+    User.where(id: Note.where(opts).pluck(:author_id))
+  end
+
   # Get project users with WATCH notification level
   def project_watchers(project)
     project_members = project_member_notification(project)
diff --git a/app/services/projects/participants_service.rb b/app/services/projects/participants_service.rb
index bcbacbff562..ae6260bcdab 100644
--- a/app/services/projects/participants_service.rb
+++ b/app/services/projects/participants_service.rb
@@ -1,10 +1,5 @@
 module Projects
   class ParticipantsService < BaseService
-    def initialize(project, user)
-      @project  = project
-      @user     = user
-    end
-
     def execute(note_type, note_id)
       participating =
         if note_type && note_id
@@ -12,7 +7,7 @@ module Projects
         else
           []
         end
-      project_members = sorted(@project.team.members)
+      project_members = sorted(project.team.members)
       participants = all_members + groups + project_members + participating
       participants.uniq
     end
@@ -20,11 +15,11 @@ module Projects
     def participants_in(type, id)
       users = case type
               when "Issue"
-                issue = @project.issues.find_by_iid(id)
-                issue ? issue.participants : []
+                issue = project.issues.find_by_iid(id)
+                issue ? issue.participants(current_user) : []
               when "MergeRequest"
-                merge_request = @project.merge_requests.find_by_iid(id)
-                merge_request ? merge_request.participants : []
+                merge_request = project.merge_requests.find_by_iid(id)
+                merge_request ? merge_request.participants(current_user) : []
               when "Commit"
                 author_ids = Note.for_commit_id(id).pluck(:author_id).uniq
                 User.where(id: author_ids)
@@ -41,14 +36,14 @@ module Projects
     end
 
     def groups
-      @user.authorized_groups.sort_by(&:path).map do |group| 
+      current_user.authorized_groups.sort_by(&:path).map do |group| 
         count = group.users.count
         { username: group.path, name: "#{group.name} (#{count})" }
       end
     end
 
     def all_members
-      count = @project.team.members.flatten.count
+      count = project.team.members.flatten.count
       [{ username: "all", name: "All Project and Group Members (#{count})" }]
     end
   end
diff --git a/app/views/projects/issues/_discussion.html.haml b/app/views/projects/issues/_discussion.html.haml
index 0d3028d50b4..288b48f4583 100644
--- a/app/views/projects/issues/_discussion.html.haml
+++ b/app/views/projects/issues/_discussion.html.haml
@@ -9,8 +9,8 @@
     .votes-holder.pull-right
       #votes= render 'votes/votes_block', votable: @issue
     .participants
-      %span= pluralize(@issue.participants.count, 'participant')
-      - @issue.participants.each do |participant|
+      %span= pluralize(@issue.participants(current_user).count, 'participant')
+      - @issue.participants(current_user).each do |participant|
         = link_to_member(@project, participant, name: false, size: 24)
     .voting_notes#notes= render "projects/notes/notes_with_form"
   %aside.col-md-3
diff --git a/app/views/projects/merge_requests/show/_participants.html.haml b/app/views/projects/merge_requests/show/_participants.html.haml
index 4f34af1737d..9c93fa55fe6 100644
--- a/app/views/projects/merge_requests/show/_participants.html.haml
+++ b/app/views/projects/merge_requests/show/_participants.html.haml
@@ -1,4 +1,4 @@
 .participants
-  %span #{@merge_request.participants.count} participants
-  - @merge_request.participants.each do |participant|
+  %span #{@merge_request.participants(current_user).count} participants
+  - @merge_request.participants(current_user).each do |participant|
     = link_to_member(@project, participant, name: false, size: 24)
diff --git a/lib/gitlab/closing_issue_extractor.rb b/lib/gitlab/closing_issue_extractor.rb
index a9fd59f03d9..ab184d95c05 100644
--- a/lib/gitlab/closing_issue_extractor.rb
+++ b/lib/gitlab/closing_issue_extractor.rb
@@ -1,21 +1,20 @@
 module Gitlab
-  module ClosingIssueExtractor
+  class ClosingIssueExtractor
     ISSUE_CLOSING_REGEX = Regexp.new(Gitlab.config.gitlab.issue_closing_pattern)
 
-    def self.closed_by_message_in_project(message, project)
-      issues = []
+    def initialize(project, current_user = nil)
+      @extractor = Gitlab::ReferenceExtractor.new(project, current_user)
+    end
 
-      unless message.nil?
-        md = message.scan(ISSUE_CLOSING_REGEX)
+    def closed_by_message(message)
+      return [] if message.nil?
+      
+      closing_statements = message.scan(ISSUE_CLOSING_REGEX).
+        map { |ref| ref[0] }.join(" ")
 
-        md.each do |ref|
-          extractor = Gitlab::ReferenceExtractor.new
-          extractor.analyze(ref[0], project)
-          issues += extractor.issues_for(project)
-        end
-      end
+      @extractor.analyze(closing_statements)
 
-      issues.uniq
+      @extractor.issues
     end
   end
 end
diff --git a/lib/gitlab/markdown.rb b/lib/gitlab/markdown.rb
index f1e2ae74a3a..8073417a16a 100644
--- a/lib/gitlab/markdown.rb
+++ b/lib/gitlab/markdown.rb
@@ -192,6 +192,7 @@ module Gitlab
         project_path = $LAST_MATCH_INFO[:project]
         if project_path
           actual_project = ::Project.find_with_namespace(project_path)
+          actual_project = nil unless can?(current_user, :read_project, actual_project)
           project_prefix = project_path
         end
 
@@ -251,6 +252,7 @@ module Gitlab
       elsif namespace = Namespace.find_by(path: identifier)
         url =
           if namespace.is_a?(Group)
+            return nil unless can?(current_user, :read_group, namespace)
             group_url(identifier, only_path: options[:reference_only_path])
           else
             user_url(identifier, only_path: options[:reference_only_path])
diff --git a/lib/gitlab/reference_extractor.rb b/lib/gitlab/reference_extractor.rb
index c0419585c4b..a502a8fe9cd 100644
--- a/lib/gitlab/reference_extractor.rb
+++ b/lib/gitlab/reference_extractor.rb
@@ -1,94 +1,94 @@
 module Gitlab
   # Extract possible GFM references from an arbitrary String for further processing.
   class ReferenceExtractor
-    attr_accessor :users, :labels, :issues, :merge_requests, :snippets, :commits, :commit_ranges
+    attr_accessor :project, :current_user, :references
 
     include ::Gitlab::Markdown
 
-    def initialize
-      @users, @labels, @issues, @merge_requests, @snippets, @commits, @commit_ranges =
-        [], [], [], [], [], [], []
+    def initialize(project, current_user = nil)
+      @project = project
+      @current_user = current_user
     end
 
-    def analyze(string, project)
-      text = string.dup
+    def can?(user, action, subject)
+      Ability.abilities.allowed?(user, action, subject)
+    end
+
+    def analyze(text)
+      text = text.dup
 
       # Remove preformatted/code blocks so that references are not included
       text.gsub!(%r{<pre>.*?</pre>|<code>.*?</code>}m) { |match| '' }
       text.gsub!(%r{^```.*?^```}m) { |match| '' }
 
-      parse_references(text, project)
+      @references = Hash.new { |hash, type| hash[type] = [] }
+      parse_references(text)
     end
 
     # Given a valid project, resolve the extracted identifiers of the requested type to
     # model objects.
 
-    def users_for(project)
-      users.map do |entry|
-        project.users.where(username: entry[:id]).first
-      end.reject(&:nil?)
-    end
-
-    def labels_for(project = nil)
-      labels.map do |entry|
-        project.labels.where(id: entry[:id]).first
-      end.reject(&:nil?)
-    end
-
-    def issues_for(project = nil)
-      issues.map do |entry|
-        if should_lookup?(project, entry[:project])
-          entry[:project].issues.where(iid: entry[:id]).first
+    def users
+      references[:user].uniq.map do |project, identifier|
+        if identifier == "all"
+          project.team.members.flatten
+        elsif namespace = Namespace.find_by(path: identifier)
+          if namespace.is_a?(Group)
+            namespace.users
+          else
+            namespace.owner
+          end
         end
-      end.reject(&:nil?)
+      end.flatten.compact.uniq
     end
 
-    def merge_requests_for(project = nil)
-      merge_requests.map do |entry|
-        if should_lookup?(project, entry[:project])
-          entry[:project].merge_requests.where(iid: entry[:id]).first
+    def labels
+      references[:label].uniq.map do |project, identifier|
+        project.labels.where(id: identifier).first
+      end.compact.uniq
+    end
+
+    def issues
+      references[:issue].uniq.map do |project, identifier|
+        if project.default_issues_tracker?
+          project.issues.where(iid: identifier).first
         end
-      end.reject(&:nil?)
+      end.compact.uniq
     end
 
-    def snippets_for(project)
-      snippets.map do |entry|
-        project.snippets.where(id: entry[:id]).first
-      end.reject(&:nil?)
+    def merge_requests
+      references[:merge_request].uniq.map do |project, identifier|
+        project.merge_requests.where(iid: identifier).first
+      end.compact.uniq
     end
 
-    def commits_for(project = nil)
-      commits.map do |entry|
-        repo = entry[:project].repository if entry[:project]
-        if should_lookup?(project, entry[:project])
-          repo.commit(entry[:id]) if repo
-        end
-      end.reject(&:nil?)
+    def snippets
+      references[:snippet].uniq.map do |project, identifier|
+        project.snippets.where(id: identifier).first
+      end.compact.uniq
     end
 
-    def commit_ranges_for(project = nil)
-      commit_ranges.map do |entry|
-        repo = entry[:project].repository if entry[:project]
-        if repo && should_lookup?(project, entry[:project])
-          from_id, to_id = entry[:id].split(/\.{2,3}/, 2)
+    def commits
+      references[:commit].uniq.map do |project, identifier|
+        repo = project.repository
+        repo.commit(identifier) if repo
+      end.compact.uniq
+    end
+
+    def commit_ranges
+      references[:commit_range].uniq.map do |project, identifier|
+        repo = project.repository
+        if repo
+          from_id, to_id = identifier.split(/\.{2,3}/, 2)
           [repo.commit(from_id), repo.commit(to_id)]
         end
-      end.reject(&:nil?)
+      end.compact.uniq
     end
 
     private
 
     def reference_link(type, identifier, project, _)
-      # Append identifier to the appropriate collection.
-      send("#{type}s") << { project: project, id: identifier }
-    end
-
-    def should_lookup?(project, entry_project)
-      if entry_project.nil?
-        false
-      else
-        project.nil? || entry_project.default_issues_tracker?
-      end
+      references[type] << [project, identifier]
     end
   end
 end
diff --git a/spec/helpers/gitlab_markdown_helper_spec.rb b/spec/helpers/gitlab_markdown_helper_spec.rb
index 0d06c6ffb82..944e743675c 100644
--- a/spec/helpers/gitlab_markdown_helper_spec.rb
+++ b/spec/helpers/gitlab_markdown_helper_spec.rb
@@ -4,6 +4,11 @@ describe GitlabMarkdownHelper do
   include ApplicationHelper
   include IssuesHelper
 
+  # TODO: Properly test this
+  def can?(*)
+    true
+  end
+
   let!(:project) { create(:project) }
   let(:empty_project) { create(:empty_project) }
 
@@ -15,6 +20,9 @@ describe GitlabMarkdownHelper do
   let(:snippet)       { create(:project_snippet, project: project) }
   let(:member)        { project.project_members.where(user_id: user).first }
 
+  # Helper expects a current_user method.
+  let(:current_user) { user }
+
   def url_helper(image_name)
     File.join(root_url, 'assets', image_name)
   end
diff --git a/spec/lib/gitlab/closing_issue_extractor_spec.rb b/spec/lib/gitlab/closing_issue_extractor_spec.rb
index c96ee78e5fd..cb7b0fbb890 100644
--- a/spec/lib/gitlab/closing_issue_extractor_spec.rb
+++ b/spec/lib/gitlab/closing_issue_extractor_spec.rb
@@ -5,126 +5,128 @@ describe Gitlab::ClosingIssueExtractor do
   let(:issue) { create(:issue, project: project) }
   let(:iid1) { issue.iid }
 
-  describe :closed_by_message_in_project do
+  subject { described_class.new(project, project.creator) }
+
+  describe "#closed_by_message" do
     context 'with a single reference' do
       it do
         message = "Awesome commit (Closes ##{iid1})"
-        expect(subject.closed_by_message_in_project(message, project)).to eq([issue])
+        expect(subject.closed_by_message(message)).to eq([issue])
       end
 
       it do
         message = "Awesome commit (closes ##{iid1})"
-        expect(subject.closed_by_message_in_project(message, project)).to eq([issue])
+        expect(subject.closed_by_message(message)).to eq([issue])
       end
 
       it do
         message = "Closed ##{iid1}"
-        expect(subject.closed_by_message_in_project(message, project)).to eq([issue])
+        expect(subject.closed_by_message(message)).to eq([issue])
       end
 
       it do
         message = "closed ##{iid1}"
-        expect(subject.closed_by_message_in_project(message, project)).to eq([issue])
+        expect(subject.closed_by_message(message)).to eq([issue])
       end
 
       it do
         message = "Closing ##{iid1}"
-        expect(subject.closed_by_message_in_project(message, project)).to eq([issue])
+        expect(subject.closed_by_message(message)).to eq([issue])
       end
 
       it do
         message = "closing ##{iid1}"
-        expect(subject.closed_by_message_in_project(message, project)).to eq([issue])
+        expect(subject.closed_by_message(message)).to eq([issue])
       end
 
       it do
         message = "Close ##{iid1}"
-        expect(subject.closed_by_message_in_project(message, project)).to eq([issue])
+        expect(subject.closed_by_message(message)).to eq([issue])
       end
 
       it do
         message = "close ##{iid1}"
-        expect(subject.closed_by_message_in_project(message, project)).to eq([issue])
+        expect(subject.closed_by_message(message)).to eq([issue])
       end
 
       it do
         message = "Awesome commit (Fixes ##{iid1})"
-        expect(subject.closed_by_message_in_project(message, project)).to eq([issue])
+        expect(subject.closed_by_message(message)).to eq([issue])
       end
 
       it do
         message = "Awesome commit (fixes ##{iid1})"
-        expect(subject.closed_by_message_in_project(message, project)).to eq([issue])
+        expect(subject.closed_by_message(message)).to eq([issue])
       end
 
       it do
         message = "Fixed ##{iid1}"
-        expect(subject.closed_by_message_in_project(message, project)).to eq([issue])
+        expect(subject.closed_by_message(message)).to eq([issue])
       end
 
       it do
         message = "fixed ##{iid1}"
-        expect(subject.closed_by_message_in_project(message, project)).to eq([issue])
+        expect(subject.closed_by_message(message)).to eq([issue])
       end
 
       it do
         message = "Fixing ##{iid1}"
-        expect(subject.closed_by_message_in_project(message, project)).to eq([issue])
+        expect(subject.closed_by_message(message)).to eq([issue])
       end
 
       it do
         message = "fixing ##{iid1}"
-        expect(subject.closed_by_message_in_project(message, project)).to eq([issue])
+        expect(subject.closed_by_message(message)).to eq([issue])
       end
 
       it do
         message = "Fix ##{iid1}"
-        expect(subject.closed_by_message_in_project(message, project)).to eq([issue])
+        expect(subject.closed_by_message(message)).to eq([issue])
       end
 
       it do
         message = "fix ##{iid1}"
-        expect(subject.closed_by_message_in_project(message, project)).to eq([issue])
+        expect(subject.closed_by_message(message)).to eq([issue])
       end
 
       it do
         message = "Awesome commit (Resolves ##{iid1})"
-        expect(subject.closed_by_message_in_project(message, project)).to eq([issue])
+        expect(subject.closed_by_message(message)).to eq([issue])
       end
 
       it do
         message = "Awesome commit (resolves ##{iid1})"
-        expect(subject.closed_by_message_in_project(message, project)).to eq([issue])
+        expect(subject.closed_by_message(message)).to eq([issue])
       end
 
       it do
         message = "Resolved ##{iid1}"
-        expect(subject.closed_by_message_in_project(message, project)).to eq([issue])
+        expect(subject.closed_by_message(message)).to eq([issue])
       end
 
       it do
         message = "resolved ##{iid1}"
-        expect(subject.closed_by_message_in_project(message, project)).to eq([issue])
+        expect(subject.closed_by_message(message)).to eq([issue])
       end
 
       it do
         message = "Resolving ##{iid1}"
-        expect(subject.closed_by_message_in_project(message, project)).to eq([issue])
+        expect(subject.closed_by_message(message)).to eq([issue])
       end
 
       it do
         message = "resolving ##{iid1}"
-        expect(subject.closed_by_message_in_project(message, project)).to eq([issue])
+        expect(subject.closed_by_message(message)).to eq([issue])
       end
 
       it do
         message = "Resolve ##{iid1}"
-        expect(subject.closed_by_message_in_project(message, project)).to eq([issue])
+        expect(subject.closed_by_message(message)).to eq([issue])
       end
 
       it do
         message = "resolve ##{iid1}"
-        expect(subject.closed_by_message_in_project(message, project)).to eq([issue])
+        expect(subject.closed_by_message(message)).to eq([issue])
       end
     end
 
@@ -137,28 +139,28 @@ describe Gitlab::ClosingIssueExtractor do
       it 'fetches issues in single line message' do
         message = "Closes ##{iid1} and fix ##{iid2}"
 
-        expect(subject.closed_by_message_in_project(message, project)).
+        expect(subject.closed_by_message(message)).
             to eq([issue, other_issue])
       end
 
       it 'fetches comma-separated issues references in single line message' do
         message = "Closes ##{iid1}, closes ##{iid2}"
 
-        expect(subject.closed_by_message_in_project(message, project)).
+        expect(subject.closed_by_message(message)).
             to eq([issue, other_issue])
       end
 
       it 'fetches comma-separated issues numbers in single line message' do
         message = "Closes ##{iid1}, ##{iid2} and ##{iid3}"
 
-        expect(subject.closed_by_message_in_project(message, project)).
+        expect(subject.closed_by_message(message)).
             to eq([issue, other_issue, third_issue])
       end
 
       it 'fetches issues in multi-line message' do
         message = "Awesome commit (closes ##{iid1})\nAlso fixes ##{iid2}"
 
-        expect(subject.closed_by_message_in_project(message, project)).
+        expect(subject.closed_by_message(message)).
             to eq([issue, other_issue])
       end
 
@@ -166,7 +168,7 @@ describe Gitlab::ClosingIssueExtractor do
         message = "Awesome commit (closes ##{iid1})\n"\
                   "Also fixing issues ##{iid2}, ##{iid3} and #4"
 
-        expect(subject.closed_by_message_in_project(message, project)).
+        expect(subject.closed_by_message(message)).
             to eq([issue, other_issue, third_issue])
       end
     end
diff --git a/spec/lib/gitlab/reference_extractor_spec.rb b/spec/lib/gitlab/reference_extractor_spec.rb
index b3f4bb5aeda..c9fb62b61ae 100644
--- a/spec/lib/gitlab/reference_extractor_spec.rb
+++ b/spec/lib/gitlab/reference_extractor_spec.rb
@@ -1,73 +1,76 @@
 require 'spec_helper'
 
 describe Gitlab::ReferenceExtractor do
+  let(:project) { create(:project) }
+  subject { Gitlab::ReferenceExtractor.new(project, project.creator) }
+
   it 'extracts username references' do
-    subject.analyze('this contains a @user reference', nil)
-    expect(subject.users).to eq([{ project: nil, id: 'user' }])
+    subject.analyze('this contains a @user reference')
+    expect(subject.references[:user]).to eq([[project, 'user']])
   end
 
   it 'extracts issue references' do
-    subject.analyze('this one talks about issue #1234', nil)
-    expect(subject.issues).to eq([{ project: nil, id: '1234' }])
+    subject.analyze('this one talks about issue #1234')
+    expect(subject.references[:issue]).to eq([[project, '1234']])
   end
 
   it 'extracts JIRA issue references' do
-    subject.analyze('this one talks about issue JIRA-1234', nil)
-    expect(subject.issues).to eq([{ project: nil, id: 'JIRA-1234' }])
+    subject.analyze('this one talks about issue JIRA-1234')
+    expect(subject.references[:issue]).to eq([[project, 'JIRA-1234']])
   end
 
   it 'extracts merge request references' do
-    subject.analyze("and here's !43, a merge request", nil)
-    expect(subject.merge_requests).to eq([{ project: nil, id: '43' }])
+    subject.analyze("and here's !43, a merge request")
+    expect(subject.references[:merge_request]).to eq([[project, '43']])
   end
 
   it 'extracts snippet ids' do
-    subject.analyze('snippets like $12 get extracted as well', nil)
-    expect(subject.snippets).to eq([{ project: nil, id: '12' }])
+    subject.analyze('snippets like $12 get extracted as well')
+    expect(subject.references[:snippet]).to eq([[project, '12']])
   end
 
   it 'extracts commit shas' do
-    subject.analyze('commit shas 98cf0ae3 are pulled out as Strings', nil)
-    expect(subject.commits).to eq([{ project: nil, id: '98cf0ae3' }])
+    subject.analyze('commit shas 98cf0ae3 are pulled out as Strings')
+    expect(subject.references[:commit]).to eq([[project, '98cf0ae3']])
   end
 
   it 'extracts commit ranges' do
-    subject.analyze('here you go, a commit range: 98cf0ae3...98cf0ae4', nil)
-    expect(subject.commit_ranges).to eq([{ project: nil, id: '98cf0ae3...98cf0ae4' }])
+    subject.analyze('here you go, a commit range: 98cf0ae3...98cf0ae4')
+    expect(subject.references[:commit_range]).to eq([[project, '98cf0ae3...98cf0ae4']])
   end
 
   it 'extracts multiple references and preserves their order' do
-    subject.analyze('@me and @you both care about this', nil)
-    expect(subject.users).to eq([
-      { project: nil, id: 'me' },
-      { project: nil, id: 'you' }
+    subject.analyze('@me and @you both care about this')
+    expect(subject.references[:user]).to eq([
+      [project, 'me'],
+      [project, 'you']
     ])
   end
 
   it 'leaves the original note unmodified' do
     text = 'issue #123 is just the worst, @user'
-    subject.analyze(text, nil)
+    subject.analyze(text)
     expect(text).to eq('issue #123 is just the worst, @user')
   end
 
   it 'extracts no references for <pre>..</pre> blocks' do
-    subject.analyze("<pre>def puts '#1 issue'\nend\n</pre>```", nil)
+    subject.analyze("<pre>def puts '#1 issue'\nend\n</pre>```")
     expect(subject.issues).to be_blank
   end
 
   it 'extracts no references for <code>..</code> blocks' do
-    subject.analyze("<code>def puts '!1 request'\nend\n</code>```", nil)
+    subject.analyze("<code>def puts '!1 request'\nend\n</code>```")
     expect(subject.merge_requests).to be_blank
   end
 
   it 'extracts no references for code blocks with language' do
-    subject.analyze("this code:\n```ruby\ndef puts '#1 issue'\nend\n```", nil)
+    subject.analyze("this code:\n```ruby\ndef puts '#1 issue'\nend\n```")
     expect(subject.issues).to be_blank
   end
 
   it 'extracts issue references for invalid code blocks' do
-    subject.analyze('test: ```this one talks about issue #1234```', nil)
-    expect(subject.issues).to eq([{ project: nil, id: '1234' }])
+    subject.analyze('test: ```this one talks about issue #1234```')
+    expect(subject.references[:issue]).to eq([[project, '1234']])
   end
 
   it 'handles all possible kinds of references' do
@@ -75,83 +78,79 @@ describe Gitlab::ReferenceExtractor do
     expect(subject).to respond_to(*accessors)
   end
 
-  context 'with a project' do
-    let(:project) { create(:project) }
+  it 'accesses valid user objects' do
+    @u_foo = create(:user, username: 'foo')
+    @u_bar = create(:user, username: 'bar')
+    @u_offteam = create(:user, username: 'offteam')
 
-    it 'accesses valid user objects on the project team' do
-      @u_foo = create(:user, username: 'foo')
-      @u_bar = create(:user, username: 'bar')
-      create(:user, username: 'offteam')
+    project.team << [@u_foo, :reporter]
+    project.team << [@u_bar, :guest]
 
-      project.team << [@u_foo, :reporter]
-      project.team << [@u_bar, :guest]
+    subject.analyze('@foo, @baduser, @bar, and @offteam')
+    expect(subject.users).to eq([@u_foo, @u_bar, @u_offteam])
+  end
 
-      subject.analyze('@foo, @baduser, @bar, and @offteam', project)
-      expect(subject.users_for(project)).to eq([@u_foo, @u_bar])
-    end
+  it 'accesses valid issue objects' do
+    @i0 = create(:issue, project: project)
+    @i1 = create(:issue, project: project)
 
-    it 'accesses valid issue objects' do
-      @i0 = create(:issue, project: project)
-      @i1 = create(:issue, project: project)
+    subject.analyze("##{@i0.iid}, ##{@i1.iid}, and #999.")
+    expect(subject.issues).to eq([@i0, @i1])
+  end
 
-      subject.analyze("##{@i0.iid}, ##{@i1.iid}, and #999.", project)
-      expect(subject.issues_for(project)).to eq([@i0, @i1])
-    end
+  it 'accesses valid merge requests' do
+    @m0 = create(:merge_request, source_project: project, target_project: project, source_branch: 'aaa')
+    @m1 = create(:merge_request, source_project: project, target_project: project, source_branch: 'bbb')
 
-    it 'accesses valid merge requests' do
-      @m0 = create(:merge_request, source_project: project, target_project: project, source_branch: 'aaa')
-      @m1 = create(:merge_request, source_project: project, target_project: project, source_branch: 'bbb')
+    subject.analyze("!999, !#{@m1.iid}, and !#{@m0.iid}.")
+    expect(subject.merge_requests).to eq([@m1, @m0])
+  end
 
-      subject.analyze("!999, !#{@m1.iid}, and !#{@m0.iid}.", project)
-      expect(subject.merge_requests_for(project)).to eq([@m1, @m0])
-    end
+  it 'accesses valid snippets' do
+    @s0 = create(:project_snippet, project: project)
+    @s1 = create(:project_snippet, project: project)
+    @s2 = create(:project_snippet)
 
-    it 'accesses valid snippets' do
-      @s0 = create(:project_snippet, project: project)
-      @s1 = create(:project_snippet, project: project)
-      @s2 = create(:project_snippet)
+    subject.analyze("$#{@s0.id}, $999, $#{@s2.id}, $#{@s1.id}")
+    expect(subject.snippets).to eq([@s0, @s1])
+  end
 
-      subject.analyze("$#{@s0.id}, $999, $#{@s2.id}, $#{@s1.id}", project)
-      expect(subject.snippets_for(project)).to eq([@s0, @s1])
-    end
+  it 'accesses valid commits' do
+    commit = project.repository.commit('master')
 
-    it 'accesses valid commits' do
-      commit = project.repository.commit('master')
+    subject.analyze("this references commits #{commit.sha[0..6]} and 012345")
+    extracted = subject.commits
+    expect(extracted.size).to eq(1)
+    expect(extracted[0].sha).to eq(commit.sha)
+    expect(extracted[0].message).to eq(commit.message)
+  end
 
-      subject.analyze("this references commits #{commit.sha[0..6]} and 012345",
-                      project)
-      extracted = subject.commits_for(project)
-      expect(extracted.size).to eq(1)
-      expect(extracted[0].sha).to eq(commit.sha)
-      expect(extracted[0].message).to eq(commit.message)
-    end
+  it 'accesses valid commit ranges' do
+    commit = project.repository.commit('master')
+    earlier_commit = project.repository.commit('master~2')
 
-    it 'accesses valid commit ranges' do
-      commit = project.repository.commit('master')
-      earlier_commit = project.repository.commit('master~2')
-
-      subject.analyze("this references commits #{earlier_commit.sha[0..6]}...#{commit.sha[0..6]}",
-                      project)
-      extracted = subject.commit_ranges_for(project)
-      expect(extracted.size).to eq(1)
-      expect(extracted[0][0].sha).to eq(earlier_commit.sha)
-      expect(extracted[0][0].message).to eq(earlier_commit.message)
-      expect(extracted[0][1].sha).to eq(commit.sha)
-      expect(extracted[0][1].message).to eq(commit.message)
-    end
+    subject.analyze("this references commits #{earlier_commit.sha[0..6]}...#{commit.sha[0..6]}")
+    extracted = subject.commit_ranges
+    expect(extracted.size).to eq(1)
+    expect(extracted[0][0].sha).to eq(earlier_commit.sha)
+    expect(extracted[0][0].message).to eq(earlier_commit.message)
+    expect(extracted[0][1].sha).to eq(commit.sha)
+    expect(extracted[0][1].message).to eq(commit.message)
   end
 
   context 'with a project with an underscore' do
-    let(:project) { create(:project, path: 'test_project') }
-    let(:issue) { create(:issue, project: project) }
+    let(:other_project) { create(:project, path: 'test_project') }
+    let(:issue) { create(:issue, project: other_project) }
+
+    before do
+      other_project.team << [project.creator, :developer]
+    end
 
     it 'handles project issue references' do
-      subject.analyze("this refers issue #{project.path_with_namespace}##{issue.iid}",
-          project)
-      extracted = subject.issues_for(project)
+      subject.analyze("this refers issue #{other_project.path_with_namespace}##{issue.iid}")
+      extracted = subject.issues
       expect(extracted.size).to eq(1)
       expect(extracted).to eq([issue])
     end
-
   end
 end