Separate observing of Note and MergeRequests

* Move is_assigned? and is_being_xx? methods to IssueCommonality

  This is behavior merge requests have in common with issues. Moved
  methods to IssueCommonality role. Put specs directly into
  merge_request_spec because setup differs for issues and MRs
  specifically in the "closed" factory to use.

* Add MergeRequestObserver. Parallels IssueObserver in almost every way.

  Ripe for refactoring.

* Rename MailerObserver to NoteObserver

  With merge request observing moved out of MailerObserver, all that
  was left was Note logic. Renamed to NoteObserver, added tests and
  updated application config for new observer names. Refactored
  NoteObserver to use the note's author and not rely on current_user.

* Set current_user for MergeRequestObserver

  IssueObserver and MergeRequestObserver are the only observers that
  need a reference to the current_user that they cannot look up on
  the objects they are observing.

11 files changed, 445 insertions, 102 deletions

diff --git a/app/controllers/application_controller.rb b/app/controllers/application_controller.rb
index c4c99204e03..b597795a519 100644
--- a/app/controllers/application_controller.rb
+++ b/app/controllers/application_controller.rb
@@ -1,7 +1,6 @@
 class ApplicationController < ActionController::Base
   before_filter :authenticate_user!
   before_filter :reject_blocked!
-  before_filter :set_current_user_for_mailer
   before_filter :set_current_user_for_observers
   before_filter :dev_tools if Rails.env == 'development'
 
@@ -41,11 +40,8 @@ class ApplicationController < ActionController::Base
     end
   end
 
-  def set_current_user_for_mailer
-    MailerObserver.current_user = current_user
-  end
-
   def set_current_user_for_observers
+    MergeRequestObserver.current_user = current_user
     IssueObserver.current_user = current_user
   end
 
diff --git a/app/models/issue.rb b/app/models/issue.rb
index 5450bb499a8..3dd1c8c8991 100644
--- a/app/models/issue.rb
+++ b/app/models/issue.rb
@@ -14,22 +14,6 @@ class Issue < ActiveRecord::Base
   def self.open_for(user)
     opened.assigned(user)
   end
-
-  def is_assigned?
-    !!assignee_id
-  end
-
-  def is_being_reassigned?
-    assignee_id_changed?
-  end
-
-  def is_being_closed?
-    closed_changed? && closed
-  end
-
-  def is_being_reopened?
-    closed_changed? && !closed
-  end
 end
 
 # == Schema Information
diff --git a/app/observers/mailer_observer.rb b/app/observers/mailer_observer.rb
deleted file mode 100644
index 331aaa35e3d..00000000000
--- a/app/observers/mailer_observer.rb
+++ /dev/null
@@ -1,80 +0,0 @@
-class MailerObserver < ActiveRecord::Observer
-  observe :note, :merge_request
-  cattr_accessor :current_user
-
-  def after_create(model)
-    new_note(model) if model.kind_of?(Note)
-    new_merge_request(model) if model.kind_of?(MergeRequest)
-  end
-
-  def after_update(model)
-    changed_merge_request(model) if model.kind_of?(MergeRequest)
-  end
-
-  protected
-
-  def new_note(note)
-    if note.notify
-      # Notify whole team except author of note
-      notify_note(note)
-    elsif note.notify_author
-      # Notify only author of resource
-      Notify.note_commit_email(note.commit_author.id, note.id).deliver
-    else
-      # Otherwise ignore it
-      nil
-    end
-  end
-
-  def notify_note note
-    # reject author of note from mail list
-    users = note.project.users.reject { |u| u.id == current_user.id }
-
-    users.each do |u|
-      case note.noteable_type
-      when "Commit"; Notify.note_commit_email(u.id, note.id).deliver
-      when "Issue";  Notify.note_issue_email(u.id, note.id).deliver
-      when "Wiki";  Notify.note_wiki_email(u.id, note.id).deliver
-      when "MergeRequest"; Notify.note_merge_request_email(u.id, note.id).deliver
-      when "Snippet"; true
-      else
-        Notify.note_wall_email(u.id, note.id).deliver
-      end
-    end
-  end
-
-  def new_merge_request(merge_request)
-    if merge_request.assignee && merge_request.assignee != current_user
-      Notify.new_merge_request_email(merge_request.id).deliver
-    end
-  end
-
-  def changed_merge_request(merge_request)
-    status_notify_and_comment merge_request, :reassigned_merge_request_email
-  end
-
-  # This method used for Issues & Merge Requests
-  #
-  # It create a comment for Issue or MR if someone close/reopen.
-  # It also notify via email if assignee was changed 
-  #
-  def status_notify_and_comment target, mail_method
-    # If assigne changed - notify to recipients
-    if target.assignee_id_changed?
-      recipients_ids = target.assignee_id_was, target.assignee_id
-      recipients_ids.delete current_user.id
-
-      recipients_ids.each do |recipient_id|
-        Notify.send(mail_method, recipient_id, target.id, target.assignee_id_was).deliver
-      end
-    end
-
-    # Create comment about status changed
-    if target.closed_changed?
-      note = Note.new(noteable: target, project: target.project)
-      note.author = current_user
-      note.note = "_Status changed to #{target.closed ? 'closed' : 'reopened'}_"
-      note.save()
-    end
-  end
-end
diff --git a/app/observers/merge_request_observer.rb b/app/observers/merge_request_observer.rb
new file mode 100644
index 00000000000..9090794ded2
--- /dev/null
+++ b/app/observers/merge_request_observer.rb
@@ -0,0 +1,31 @@
+class MergeRequestObserver < ActiveRecord::Observer
+  cattr_accessor :current_user
+
+  def after_create(merge_request)
+    if merge_request.assignee && merge_request.assignee != current_user
+      Notify.new_merge_request_email(merge_request.id).deliver
+    end
+  end
+
+  def after_update(merge_request)
+    send_reassigned_email(merge_request) if merge_request.is_being_reassigned?
+
+    status = nil
+    status = 'closed' if merge_request.is_being_closed?
+    status = 'reopened' if merge_request.is_being_reopened?
+    if status
+      Note.create_status_change_note(merge_request, current_user, status)
+    end
+  end
+
+  protected
+
+  def send_reassigned_email(merge_request)
+      recipients_ids = merge_request.assignee_id_was, merge_request.assignee_id
+      recipients_ids.delete current_user.id
+
+      recipients_ids.each do |recipient_id|
+        Notify.reassigned_merge_request_email(recipient_id, merge_request.id, merge_request.assignee_id_was).deliver
+      end
+  end
+end
diff --git a/app/observers/note_observer.rb b/app/observers/note_observer.rb
new file mode 100644
index 00000000000..844848567eb
--- /dev/null
+++ b/app/observers/note_observer.rb
@@ -0,0 +1,36 @@
+class NoteObserver < ActiveRecord::Observer
+
+  def after_create(note)
+    if note.notify
+      # Notify whole team except author of note
+      notify_team_of_new_note(note)
+    elsif note.notify_author
+      # Notify only author of resource
+      Notify.note_commit_email(note.commit_author.id, note.id).deliver
+    else
+      # Otherwise ignore it
+      nil
+    end
+  end
+
+  protected
+
+  def notify_team_of_new_note(note)
+    team_without_note_author(note).map do |u|
+      case note.noteable_type
+      when "Commit"; Notify.note_commit_email(u.id, note.id).deliver
+      when "Issue";  Notify.note_issue_email(u.id, note.id).deliver
+      when "Wiki";  Notify.note_wiki_email(u.id, note.id).deliver
+      when "MergeRequest"; Notify.note_merge_request_email(u.id, note.id).deliver
+      when "Wall"; Notify.note_wall_email(u.id, note.id).deliver
+      when "Snippet"; true # no notifications for snippets?
+      else
+        true
+      end
+    end
+  end
+
+  def team_without_note_author(note)
+    note.project.users.reject { |u| u.id == note.author.id }
+  end
+end
diff --git a/app/roles/issue_commonality.rb b/app/roles/issue_commonality.rb
index 3d9074867b7..2d10bfec866 100644
--- a/app/roles/issue_commonality.rb
+++ b/app/roles/issue_commonality.rb
@@ -46,4 +46,21 @@ module IssueCommonality
   def new?
     today? && created_at == updated_at
   end
+
+  def is_assigned?
+    !!assignee_id
+  end
+
+  def is_being_reassigned?
+    assignee_id_changed?
+  end
+
+  def is_being_closed?
+    closed_changed? && closed
+  end
+
+  def is_being_reopened?
+    closed_changed? && !closed
+  end
+
 end
diff --git a/config/application.rb b/config/application.rb
index 1189035fa86..74ed330effd 100644
--- a/config/application.rb
+++ b/config/application.rb
@@ -23,7 +23,15 @@ module Gitlab
     # config.plugins = [ :exception_notification, :ssl_requirement, :all ]
 
     # Activate observers that should always be running.
-    config.active_record.observers = :mailer_observer, :activity_observer, :project_observer, :key_observer, :issue_observer, :user_observer, :system_hook_observer, :users_project_observer
+    config.active_record.observers = :activity_observer,
+                                     :issue_observer,
+                                     :key_observer,
+                                     :merge_request_observer,
+                                     :note_observer,
+                                     :project_observer,
+                                     :system_hook_observer,
+                                     :user_observer,
+                                     :users_project_observer
 
     # Set Time.zone default to the specified zone and make Active Record auto-convert to this zone.
     # Run "rake -D time" for a list of tasks for finding time zone names. Default is UTC.
diff --git a/spec/factories.rb b/spec/factories.rb
index cb3541cc7f2..0258f8920e9 100644
--- a/spec/factories.rb
+++ b/spec/factories.rb
@@ -76,6 +76,12 @@ FactoryGirl.define do
     project
     source_branch "master"
     target_branch "stable"
+
+    trait :closed do
+      closed true
+    end
+
+    factory :closed_merge_request, traits: [:closed]
   end
 
   factory :note do
diff --git a/spec/models/merge_request_spec.rb b/spec/models/merge_request_spec.rb
index 91d404f79c0..be40c561adb 100644
--- a/spec/models/merge_request_spec.rb
+++ b/spec/models/merge_request_spec.rb
@@ -50,4 +50,47 @@ describe MergeRequest do
       merge_request.mr_and_commit_notes.count.should == 2
     end
   end
+
+  subject { Factory.create(:merge_request) }
+
+  describe '#is_being_reassigned?' do
+    it 'returns true if the merge_request assignee has changed' do
+      subject.assignee = Factory(:user)
+      subject.is_being_reassigned?.should be_true
+    end
+    it 'returns false if the merge request assignee has not changed' do
+      subject.is_being_reassigned?.should be_false
+    end
+  end
+
+  describe '#is_being_closed?' do
+    it 'returns true if the closed attribute has changed and is now true' do
+      subject.closed = true
+      subject.is_being_closed?.should be_true
+    end
+    it 'returns false if the closed attribute has changed and is now false' do
+      merge_request = Factory.create(:closed_merge_request)
+      merge_request.closed = false
+      merge_request.is_being_closed?.should be_false
+    end
+    it 'returns false if the closed attribute has not changed' do
+      subject.is_being_closed?.should be_false
+    end
+  end
+
+
+  describe '#is_being_reopened?' do
+    it 'returns true if the closed attribute has changed and is now false' do
+      merge_request = Factory.create(:closed_merge_request)
+      merge_request.closed = false
+      merge_request.is_being_reopened?.should be_true
+    end
+    it 'returns false if the closed attribute has changed and is now true' do
+      subject.closed = true
+      subject.is_being_reopened?.should be_false
+    end
+    it 'returns false if the closed attribute has not changed' do
+      subject.is_being_reopened?.should be_false
+    end
+  end
 end
diff --git a/spec/observers/merge_request_observer_spec.rb b/spec/observers/merge_request_observer_spec.rb
new file mode 100644
index 00000000000..a9ba79271e3
--- /dev/null
+++ b/spec/observers/merge_request_observer_spec.rb
@@ -0,0 +1,193 @@
+require 'spec_helper'
+
+describe MergeRequestObserver do
+  let(:some_user) { double(:user, id: 1) }
+  let(:assignee) { double(:user, id: 2) }
+  let(:author) { double(:user, id: 3) }
+  let(:mr)    { double(:merge_request, id: 42, assignee: assignee, author: author) }
+
+  before(:each) { subject.stub(:current_user).and_return(some_user) }
+
+  subject { MergeRequestObserver.instance }
+
+  describe '#after_create' do
+
+    it 'is called when a merge request is created' do
+      subject.should_receive(:after_create)
+
+      MergeRequest.observers.enable :merge_request_observer do
+        Factory.create(:merge_request, project: Factory.create(:project))
+      end
+    end
+
+    it 'sends an email to the assignee' do
+      Notify.should_receive(:new_merge_request_email).with(mr.id).
+        and_return(double(deliver: true))
+
+      subject.after_create(mr)
+    end
+
+    it 'does not send an email to the assignee if assignee created the merge request' do
+      subject.stub(:current_user).and_return(assignee)
+      Notify.should_not_receive(:new_merge_request_email)
+
+      subject.after_create(mr)
+    end
+  end
+
+  context '#after_update' do
+    before(:each) do
+      mr.stub(:is_being_reassigned?).and_return(false)
+      mr.stub(:is_being_closed?).and_return(false)
+      mr.stub(:is_being_reopened?).and_return(false)
+    end
+
+    it 'is called when a merge request is changed' do
+      changed = Factory.create(:merge_request, project: Factory.create(:project))
+      subject.should_receive(:after_update)
+
+      MergeRequest.observers.enable :merge_request_observer do
+        changed.title = 'I changed'
+        changed.save
+      end
+    end
+
+    context 'a reassigned email' do
+      it 'is sent if the merge request is being reassigned' do
+        mr.should_receive(:is_being_reassigned?).and_return(true)
+        subject.should_receive(:send_reassigned_email).with(mr)
+
+        subject.after_update(mr)
+      end
+
+      it 'is not sent if the merge request is not being reassigned' do
+        mr.should_receive(:is_being_reassigned?).and_return(false)
+        subject.should_not_receive(:send_reassigned_email)
+
+        subject.after_update(mr)
+      end
+    end
+
+    context 'a status "closed"' do
+      it 'note is created if the merge request is being closed' do
+        mr.should_receive(:is_being_closed?).and_return(true)
+        Note.should_receive(:create_status_change_note).with(mr, some_user, 'closed')
+
+        subject.after_update(mr)
+      end
+
+      it 'note is not created if the merge request is not being closed' do
+        mr.should_receive(:is_being_closed?).and_return(false)
+        Note.should_not_receive(:create_status_change_note).with(mr, some_user, 'closed')
+
+        subject.after_update(mr)
+      end
+
+      it 'notification is delivered if the merge request being closed' do
+        mr.stub(:is_being_closed?).and_return(true)
+        Note.should_receive(:create_status_change_note).with(mr, some_user, 'closed')
+
+        subject.after_update(mr)
+      end
+
+      it 'notification is not delivered if the merge request not being closed' do
+        mr.stub(:is_being_closed?).and_return(false)
+        Note.should_not_receive(:create_status_change_note).with(mr, some_user, 'closed')
+
+        subject.after_update(mr)
+      end
+
+      it 'notification is delivered only to author if the merge request is being closed' do
+        mr_without_assignee = double(:merge_request, id: 42, author: author, assignee: nil)
+        mr_without_assignee.stub(:is_being_reassigned?).and_return(false)
+        mr_without_assignee.stub(:is_being_closed?).and_return(true)
+        mr_without_assignee.stub(:is_being_reopened?).and_return(false)
+        Note.should_receive(:create_status_change_note).with(mr_without_assignee, some_user, 'closed')
+
+        subject.after_update(mr_without_assignee)
+      end
+    end
+
+    context 'a status "reopened"' do
+      it 'note is created if the merge request is being reopened' do
+        mr.should_receive(:is_being_reopened?).and_return(true)
+        Note.should_receive(:create_status_change_note).with(mr, some_user, 'reopened')
+
+        subject.after_update(mr)
+      end
+
+      it 'note is not created if the merge request is not being reopened' do
+        mr.should_receive(:is_being_reopened?).and_return(false)
+        Note.should_not_receive(:create_status_change_note).with(mr, some_user, 'reopened')
+
+        subject.after_update(mr)
+      end
+
+      it 'notification is delivered if the merge request being reopened' do
+        mr.stub(:is_being_reopened?).and_return(true)
+        Note.should_receive(:create_status_change_note).with(mr, some_user, 'reopened')
+
+        subject.after_update(mr)
+      end
+
+      it 'notification is not delivered if the merge request is not being reopened' do
+        mr.stub(:is_being_reopened?).and_return(false)
+        Note.should_not_receive(:create_status_change_note).with(mr, some_user, 'reopened')
+
+        subject.after_update(mr)
+      end
+
+      it 'notification is delivered only to author if the merge request is being reopened' do
+        mr_without_assignee = double(:merge_request, id: 42, author: author, assignee: nil)
+        mr_without_assignee.stub(:is_being_reassigned?).and_return(false)
+        mr_without_assignee.stub(:is_being_closed?).and_return(false)
+        mr_without_assignee.stub(:is_being_reopened?).and_return(true)
+        Note.should_receive(:create_status_change_note).with(mr_without_assignee, some_user, 'reopened')
+
+        subject.after_update(mr_without_assignee)
+      end
+    end
+  end
+
+  describe '#send_reassigned_email' do
+    let(:previous_assignee) { double(:user, id: 3) }
+
+    before(:each) do
+      mr.stub(:assignee_id).and_return(assignee.id)
+      mr.stub(:assignee_id_was).and_return(previous_assignee.id)
+    end
+
+    def it_sends_a_reassigned_email_to(recipient)
+      Notify.should_receive(:reassigned_merge_request_email).with(recipient, mr.id, previous_assignee.id).
+        and_return(double(deliver: true))
+    end
+
+    def it_does_not_send_a_reassigned_email_to(recipient)
+      Notify.should_not_receive(:reassigned_merge_request_email).with(recipient, mr.id, previous_assignee.id)
+    end
+
+    it 'sends a reassigned email to the previous and current assignees' do
+      it_sends_a_reassigned_email_to assignee.id
+      it_sends_a_reassigned_email_to previous_assignee.id
+
+      subject.send(:send_reassigned_email, mr)
+    end
+
+    context 'does not send an email to the user who made the reassignment' do
+      it 'if the user is the assignee' do
+        subject.stub(:current_user).and_return(assignee)
+        it_sends_a_reassigned_email_to previous_assignee.id
+        it_does_not_send_a_reassigned_email_to assignee.id
+
+        subject.send(:send_reassigned_email, mr)
+      end
+      it 'if the user is the previous assignee' do
+        subject.stub(:current_user).and_return(previous_assignee)
+        it_sends_a_reassigned_email_to assignee.id
+        it_does_not_send_a_reassigned_email_to previous_assignee.id
+
+        subject.send(:send_reassigned_email, mr)
+      end
+    end
+  end
+end
diff --git a/spec/observers/note_observer_spec.rb b/spec/observers/note_observer_spec.rb
new file mode 100644
index 00000000000..fd21178918b
--- /dev/null
+++ b/spec/observers/note_observer_spec.rb
@@ -0,0 +1,109 @@
+require 'spec_helper'
+
+describe NoteObserver do
+  subject { NoteObserver.instance }
+
+  describe '#after_create' do
+    let(:note) { double :note, notify: false, notify_author: false }
+
+    it 'is called after a note is created' do
+      subject.should_receive :after_create
+
+      Note.observers.enable :note_observer do
+        Factory.create(:note)
+      end
+    end
+
+    it 'notifies team of new note when flagged to notify' do
+      note.stub(:notify).and_return(true)
+      subject.should_receive(:notify_team_of_new_note).with(note)
+
+      subject.after_create(note)
+    end
+    it 'does not notify team of new note when not flagged to notify' do
+      subject.should_not_receive(:notify_team_of_new_note).with(note)
+
+      subject.after_create(note)
+    end
+    it 'notifies the author of a commit when flagged to notify the author' do
+      note.stub(:notify_author).and_return(true)
+      note.stub(:id).and_return(42)
+      author = double :user, id: 1
+      note.stub(:commit_author).and_return(author)
+      Notify.should_receive(:note_commit_email).and_return(double(deliver: true))
+
+      subject.after_create(note)
+    end
+    it 'does not notify the author of a commit when not flagged to notify the author' do
+      Notify.should_not_receive(:note_commit_email)
+
+      subject.after_create(note)
+    end
+    it 'does nothing if no notify flags are set' do
+      subject.after_create(note).should be_nil
+    end
+  end
+
+
+  let(:team_without_author) { (1..2).map { |n| double :user, id: n } }
+
+  describe '#notify_team_of_new_note' do
+    let(:note) { double :note, id: 1 }
+
+    before :each do
+      subject.stub(:team_without_note_author).with(note).and_return(team_without_author)
+    end
+
+    context 'notifies team of a new note on' do
+      it 'a commit' do
+        note.stub(:noteable_type).and_return('Commit')
+        Notify.should_receive(:note_commit_email).twice.and_return(double(deliver: true))
+
+        subject.send(:notify_team_of_new_note, note)
+      end
+      it 'an issue' do
+        note.stub(:noteable_type).and_return('Issue')
+        Notify.should_receive(:note_issue_email).twice.and_return(double(deliver: true))
+
+        subject.send(:notify_team_of_new_note, note)
+      end
+      it 'a wiki page' do
+        note.stub(:noteable_type).and_return('Wiki')
+        Notify.should_receive(:note_wiki_email).twice.and_return(double(deliver: true))
+
+        subject.send(:notify_team_of_new_note, note)
+      end
+      it 'a merge request' do
+        note.stub(:noteable_type).and_return('MergeRequest')
+        Notify.should_receive(:note_merge_request_email).twice.and_return(double(deliver: true))
+
+        subject.send(:notify_team_of_new_note, note)
+      end
+      it 'a wall' do
+        note.stub(:noteable_type).and_return('Wall')
+        Notify.should_receive(:note_wall_email).twice.and_return(double(deliver: true))
+
+        subject.send(:notify_team_of_new_note, note)
+      end
+    end
+
+    it 'does nothing for a new note on a snippet' do
+        note.stub(:noteable_type).and_return('Snippet')
+
+        subject.send(:notify_team_of_new_note, note).should == [true, true]
+    end
+  end
+
+
+  describe '#team_without_note_author' do
+    let(:author) { double :user, id: 4 }
+
+    let(:users) { team_without_author + [author] }
+    let(:project)  { double :project, users: users }
+    let(:note) { double :note, project: project, author: author }
+
+    it 'returns the projects user without the note author included' do
+      subject.send(:team_without_note_author, note).should == team_without_author
+    end
+  end
+end