--- a/app/controllers/browse_controller.rb
+++ b/app/controllers/browse_controller.rb
@@ -48,6 +48,9 @@ class BrowseController < ApplicationController
     end
     @blob = @git.tree(@commit.tree.id, ["#{params[:path].join("/")}"]).contents.first
     render_not_found and return unless @blob
+    unless @blob.respond_to?(:data) # it's a tree
+      redirect_to project_repository_tree_path(@project, @repository, @commit.id, params[:path])
+    end
   end
   
   def raw

--- a/app/controllers/comments_controller.rb
+++ b/app/controllers/comments_controller.rb
@@ -5,6 +5,7 @@ class CommentsController < ApplicationController
   
   def index
     @comments = @repository.comments.find(:all, :include => :user)
+    @merge_request_count = @repository.merge_requests.count_open
     @atom_auto_discovery_url = formatted_project_repository_comments_path(@project, @repository, :atom)
     respond_to do |format|
       format.html { }

--- /dev/null
+++ b/app/controllers/merge_requests_controller.rb
@@ -0,0 +1,98 @@
+class MergeRequestsController < ApplicationController
+  before_filter :login_required, :except => [:index, :show]
+  before_filter :find_project
+  before_filter :find_repository
+  before_filter :find_merge_request, :except => [:index, :show, :new, :create]
+  before_filter :assert_merge_request_ownership, :except => [:index, :show, :new, :create, :resolve]
+  before_filter :assert_merge_request_resolvable, :only => [:resolve]
+  
+  def index
+    @merge_requests = @repository.merge_requests
+    @comment_count = @repository.comments.count
+    #@proposed_merge_requests = @repository.proposed_merge_requests
+  end
+  
+  def show
+    @merge_request = @repository.merge_requests.find(params[:id])
+    @commits = @merge_request.target_repository.git.commit_deltas_from(@merge_request.source_repository.git)
+  end
+  
+  def new
+    @merge_request = @repository.proposed_merge_requests.new(:user => current_user)
+    @repositories = @project.repositories.find(:all, :conditions => ["id != ?", @repository.id])
+  end
+  
+  def create
+    @merge_request = @repository.proposed_merge_requests.new(params[:merge_request])
+    @merge_request.user = current_user
+    if @merge_request.save
+      flash[:success] = "Your sent a merge request to #{@merge_request.target_repository.name}"
+      redirect_to project_repository_path(@project, @repository) and return
+    else
+      @repositories = @project.repositories.find(:all, :conditions => ["id != ?", @repository.id])
+      render :action => "new"
+    end
+  end
+  
+  def resolve
+    # TODO: put to change status
+    @merge_request.status = params[:merge_request][:status]
+    if @merge_request.save
+      flash[:notice] = "The merge request was marked as #{@merge_request.status_string}"
+    end
+    redirect_to [@project, @repository, @merge_request]      
+  end
+  
+  def edit
+    @repositories = @project.repositories.find(:all, :conditions => ["id != ?", @repository.id])
+  end
+  
+  def update
+    @merge_request.attributes = params[:merge_request]
+    if @merge_request.save
+      flash[:success] = "Merge request was updated"
+      redirect_to [@project, @repository, @merge_request]
+    else
+      @repositories = @project.repositories.find(:all, :conditions => ["id != ?", @repository.id])
+      render :action => "edit"
+    end
+  end
+  
+  def destroy
+    @merge_request.destroy
+    flash[:success] = "Merge request was retracted"
+    redirect_to project_repository_path(@project, @repository)
+  end
+  
+  protected
+    def find_repository
+      @repository = @project.repositories.find_by_name!(params[:repository_id])
+    end
+    
+    def find_merge_request
+      @merge_request = @repository.merge_requests.find(params[:id])
+    end
+    
+    def assert_merge_request_resolvable
+      unless @merge_request.resolvable_by?(current_user)
+        respond_to do |format|
+          flash[:error] = "You're not permitted to resolve this merge request"
+          format.html { redirect_to([@project, @repository, @merge_request]) }
+          format.xml  { render :text => "You're not permitted to resolve this merge request", :status => :forbidden }
+        end
+        return
+      end
+    end
+    
+    def assert_merge_request_ownership
+      if @merge_request.user != current_user
+        respond_to do |format|
+          flash[:error] = "You're not the owner of this merge request"
+          format.html { redirect_to([@project, @repository]) }
+          format.xml  { render :text => "You're not the owner of this merge request", :status => :forbidden }
+        end
+        return
+      end
+    end
+  
+end

--- a/app/controllers/repositories_controller.rb
+++ b/app/controllers/repositories_controller.rb
@@ -12,6 +12,7 @@ class RepositoriesController < ApplicationController
   def show
     @repository = @project.repositories.find_by_name!(params[:id])
     @comment_count = @repository.comments.count
+    @merge_request_count = @repository.merge_requests.count_open
     if @repository.has_commits?
       @commits = @repository.git.commits(@repository.head_candidate.name, 10)
     else

--- a/app/helpers/application_helper.rb
+++ b/app/helpers/application_helper.rb
@@ -8,7 +8,7 @@ module ApplicationHelper
   
   def linked_tag_list_as_sentence(tags)
     tags.map do |tag|
-      link_to(h(tag.name), { :action => :category, :id => tag.name })
+      link_to(h(tag.name), { :controller => "projects", :action => "category", :id => tag.name })
     end.to_sentence
   end
   

--- /dev/null
+++ b/app/helpers/merge_requests_helper.rb
@@ -0,0 +1,2 @@
+module MergeRequestsHelper
+end

--- a/app/models/mailer.rb
+++ b/app/models/mailer.rb
@@ -21,6 +21,17 @@ class Mailer < ActionMailer::Base
     @body[:url] = "http://gitorious.org/p/#{repository.project.slug}/repos/#{repository.name}"
   end
   
+  def merge_request_notification(merge_request)
+    setup_email(merge_request.target_repository.user)
+    @subject += %Q{#{merge_request.source_repository.user.login} has requested a merge in #{merge_request.target_repository.project.title}}
+    @body[:merge_request] = merge_request
+    @body[:project] = merge_request.target_repository.project
+    url = "http://gitorious.org/p/#{merge_request.target_repository.project.slug}"
+    url << "/repos/#{merge_request.target_repository.name}"
+    url << "/merge_requests/#{merge_request.id}"
+    @body[:url] = url
+  end
+  
   protected
     def setup_email(user)
       @recipients  = "#{user.email}"

--- /dev/null
+++ b/app/models/merge_request.rb
@@ -0,0 +1,42 @@
+class MergeRequest < ActiveRecord::Base
+  belongs_to :user
+  belongs_to :source_repository, :class_name => 'Repository'
+  belongs_to :target_repository, :class_name => 'Repository'
+  
+  attr_protected :user, :status
+  
+  STATUS_OPEN = 0
+  STATUS_MERGED = 1
+  STATUS_REJECTED = 2
+  
+  validates_presence_of :user, :source_repository, :target_repository
+  attr_protected :user_id
+  
+  def self.statuses
+    { "Open" => STATUS_OPEN, "Merged" => STATUS_MERGED, "Rejected" => STATUS_REJECTED }
+  end
+  
+  def self.count_open
+    count(:all, :conditions => {:status => STATUS_OPEN})
+  end
+  
+  def status_string
+    self.class.statuses.invert[status].downcase
+  end
+  
+  def open?
+    status == STATUS_OPEN
+  end
+  
+  def merged?
+    status == STATUS_MERGED
+  end
+  
+  def rejected?
+    status == STATUS_REJECTED
+  end
+  
+  def resolvable_by?(candidate)
+    candidate == target_repository.user
+  end
+end

--- /dev/null
+++ b/app/models/merge_request_observer.rb
@@ -0,0 +1,7 @@
+class MergeRequestObserver < ActiveRecord::Observer
+  
+  def after_create(record)
+    Mailer.deliver_merge_request_notification(record)
+  end
+  
+end
\ No newline at end of file

--- a/app/models/repository.rb
+++ b/app/models/repository.rb
@@ -5,6 +5,9 @@ class Repository < ActiveRecord::Base
   has_many    :committerships, :dependent => :destroy
   has_many    :committers, :through => :committerships, :source => :user
   has_many    :comments, :dependent => :destroy
+  has_many    :merge_requests, :foreign_key => 'target_repository_id', :order => "status, id desc"
+  has_many    :proposed_merge_requests, :foreign_key => 'source_repository_id', 
+                :class_name => 'MergeRequest', :order => "id desc"
   
   validates_presence_of :user_id, :project_id, :name
   validates_format_of :name, :with => /^[a-z0-9_\-]+$/i,

--- a/app/views/comments/index.html.erb
+++ b/app/views/comments/index.html.erb
@@ -15,6 +15,8 @@
 <ul class="tab_menu">
   <li><%= link_to "Recent commits", project_repository_path(@project, @repository) -%></li>
   <li class="selected">Comments (<%= @comments.size -%>)</li>
+  <li><%= link_to "merge requests(#{@merge_request_count})", 
+            project_repository_merge_requests_path(@project, @repository) -%></li>
 </ul>
 
 <%= render :partial => @comments -%>

--- /dev/null
+++ b/app/views/mailer/merge_request_notification.rhtml
@@ -0,0 +1,10 @@
+Hello <%= @merge_request.target_repository.user.login -%>,
+
+<%= @merge_request.source_repository.user.login -%> has requested that you merge <%= @merge_request.source_repository.name -%> with <%= @merge_request.target_repository.name -%> in the <%= @project.title -%> project.
+
+You can review the request and its commits here:
+<%= @url %>
+
+Thank you
+
+http://gitorious.org

--- /dev/null
+++ b/app/views/merge_requests/_form.html.erb
@@ -0,0 +1,10 @@
+<p>
+  <%= form.label :target_repository_id -%><br />
+  <small class="hint">The one you wish this repository should be merged with</small><br />
+  <%= form.select :target_repository_id, @repositories.map{|r| [r.name, r.id] } -%>
+</p>
+<p>
+  <%= form.label :proposal -%><br />
+  <small class="hint">A short summary of your changes</small><br />
+  <%= form.text_area :proposal, :class => "text medium" -%>
+</p>
\ No newline at end of file

--- /dev/null
+++ b/app/views/merge_requests/_merge_request.html.erb
@@ -0,0 +1,17 @@
+<% no_link ||= false -%>
+
+<div class="merge_request_summary <%= merge_request.status_string -%>">
+  <p class="status">[<span><%= merge_request.status_string -%></span>]</p>
+  <h5>
+    <%= link_to h(merge_request.source_repository.name), [@project, merge_request.source_repository] -%> 
+    has requested a merge with <%= link_to h(merge_request.target_repository.name), [@project, merge_request.target_repository] -%>:
+  </h5>
+  <div class="proposal"><%= sanitize(simple_format(merge_request.proposal)) -%></div>
+  <p class="byline">
+    <%= link_to(h(merge_request.user.login), merge_request.user) -%> | 
+    <%= merge_request.created_at.to_s(:short) -%> 
+    <% unless no_link -%>
+      | <strong><%= link_to "Review merge request &#x2192;", [@project, @repository, merge_request] -%></strong>
+    <% end -%>
+  </p>
+</div>
\ No newline at end of file

--- /dev/null
+++ b/app/views/merge_requests/index.html.erb
@@ -0,0 +1,26 @@
+<% @page_title = "Merge requests in #{h(@repository.name)}" -%>
+<h1>
+  Merge requests in <%=h @repository.name  -%>
+</h1>
+
+<%= render :partial => "repositories/infobox" -%>
+
+<p class="hint">
+  A "merge request" is a notification from one repository to another that
+  would like their changes to be merged upstream. 
+</p>
+
+<ul class="tab_menu">
+  <li><%= link_to "Recent commits", project_repository_path(@project, @repository) -%></li>
+  <li><%= link_to "comments (#{@comment_count})", 
+            project_repository_comments_path(@project, @repository) -%></li>
+  <li class="selected">merge requests(<%= @merge_requests.select{|mr| mr.open? }.size -%>)</li>
+</ul>
+
+<% if @merge_requests.blank? -%>
+  <p>
+    <em>No merge requests yet</em><br />
+  </p>
+<% else -%>
+  <%= render :partial => @merge_requests -%>
+<% end -%>

--- /dev/null
+++ b/app/views/merge_requests/new.html.erb
@@ -0,0 +1,9 @@
+<h1>Create a merge request</h1>
+
+<%= error_messages_for :merge_request -%>
+
+<% form_for [@project, @repository, @merge_request] do |f| -%>
+  <%= render :partial => "form", :locals => {:form => f} -%>
+  
+  <%= f.submit "Create merge request" -%>
+<% end -%>
\ No newline at end of file

--- /dev/null
+++ b/app/views/merge_requests/show.html.erb
@@ -0,0 +1,35 @@
+<h1>
+  Reviewing merge request "<%=h @merge_request.source_repository.name -%>" &#x2192; 
+  "<%= @merge_request.target_repository.name -%>"
+</h1>
+
+<%= render :partial => @merge_request, :locals => { :no_link => true } -%>
+
+<% if @merge_request.resolvable_by?(current_user) -%>
+  <% form_for @merge_request, 
+      :url => resolve_project_repository_merge_request_path(@project, 
+              @repository, @merge_request) do |f| -%>
+    <p>
+      <%= f.label :status -%><br />
+      <%= f.select :status, MergeRequest.statuses.sort_by{|k,v| v } -%><br />
+      <%= f.submit "Update merge request" -%></p>
+  <% end -%>
+
+  <% if @merge_request.open? -%>
+  <p>The simplest way to merge in these changes is to simply pull them in with the following command:</p>
+  <pre>git pull <%= @merge_request.source_repository.clone_url -%></pre>
+  <% end -%>
+<% end -%>
+
+<% if @merge_request.open? -%>
+<h2>Commits that would be merged:</h2>
+
+<ul class="shortlog">
+  <% @commits.each do |commit| -%>
+    <li><a href=""><%= link_to h(commit.id_abbrev), 
+      project_repository_commit_path(@project, @merge_request.source_repository, commit.id) -%></a> 
+    by <strong><%=h commit.committer.name -%></strong> <%=h time_ago_in_words(commit.committed_date) -%> ago
+    <div class="commit_message"><%= simple_format(h(commit.message)) -%></div></li>
+  <% end -%>
+</ul>
+<% end -%>
\ No newline at end of file

--- a/app/views/projects/index.atom.builder
+++ b/app/views/projects/index.atom.builder
@@ -8,7 +8,7 @@ atom_feed do |feed|
       entry.title(project.title)
       entry.content(project.description)
       entry.author do |author|
-        author.name("Gitorious")
+        author.name(project.user.login)
       end
     end
   end

--- a/app/views/repositories/_infobox.html.erb
+++ b/app/views/repositories/_infobox.html.erb
@@ -7,15 +7,11 @@
   <% end -%>
   <li><strong>Created:</strong> <%= @repository.created_at.to_s(:short) -%></li>
   <li>
-    <strong>Clone url:</strong> <code><%=h @repository.clone_url -%></code> 
+    <strong>Public clone url:</strong> <code><%=h @repository.clone_url -%></code> 
     <small><%= link_to_function "More info…", "$('detailed_clone_info').toggle()" -%></small>
     <div id="detailed_clone_info" class="info_hint" style="display:none">
       You can clone this repository with the following command:<br />
-      <% if logged_in? && current_user.can_write_to?(@repository) -%>
-        <code>git clone <%= @repository.push_url -%></code>
-      <% else -%>
-        <code>git clone <%= @repository.clone_url -%></code>
-      <% end -%>
+      <code>git clone <%= @repository.clone_url -%></code>
     </div>
   </li>
   <li>
@@ -23,7 +19,9 @@
     <small><%= link_to_function "More info…", "$('detailed_http_clone_info').toggle()" -%></small>
     <div id="detailed_http_clone_info" class="info_hint" style="display:none">
       You can clone this repository with the following command:<br />
-        <code>git clone <%= @repository.http_clone_url -%></code>
+        <code>git clone <%= @repository.http_clone_url -%></code><br />
+        <small>(note that cloning over HTTP is slightly slower, but useful 
+          if you're behind a firewall)</small>
     </div>
   </li>
   <% if logged_in? && current_user.can_write_to?(@repository) -%>
@@ -31,8 +29,8 @@
       <strong>Push url:</strong> <code><%=h @repository.push_url -%></code>
       <small><%= link_to_function "More info…", "$('detailed_push_info').toggle()" -%></small>
       <div id="detailed_push_info" class="info_hint" style="display:none">
-You can run "<code>git push git@gitorious.org:tumbline/mainline.git</code>", or 
-you can setup a remote by doing the following:
+        You can run "<code>git push <%= @repository.push_url %></code>", or 
+        you can setup a remote by doing the following:
 <pre>
 git remote add origin <%= @repository.push_url %>
 # to push the master branch to the origin remote we added above:

--- a/app/views/repositories/show.html.erb
+++ b/app/views/repositories/show.html.erb
@@ -9,7 +9,10 @@
   
   <ul class="tab_menu">
     <li class="selected">Recent commits</li>
-    <li><%= link_to "comments (#{@comment_count})", project_repository_comments_path(@project, @repository) -%></li>
+    <li><%= link_to "comments (#{@comment_count})", 
+              project_repository_comments_path(@project, @repository) -%></li>
+    <li><%= link_to "merge requests(#{@merge_request_count})", 
+              project_repository_merge_requests_path(@project, @repository) -%></li>
   </ul>
 
   <h2>Recent commits</h2>
@@ -33,9 +36,10 @@
 <% content_for :sidebar do -%>  
   <ul class="links">
     <% if @repository.ready? -%>
-      <li><%= link_to "Clone this repository", new_project_repository_path(@project, @repository) -%></li>
+      <li><%= link_to "Clone repository", new_project_repository_path(@project, @repository) -%></li>
     <% end -%>
     <% if @repository.user == current_user -%>
+      <li><%= link_to "Request merge", new_project_repository_merge_request_path(@project, @repository) -%></li>
       <li><%= link_to "Add committer", 
               { :controller => "committers", :action => "new", :project_id => @project, 
                 :repository_id => @repository } -%></li>

--- a/config/environment.rb
+++ b/config/environment.rb
@@ -45,7 +45,11 @@ Rails::Initializer.run do |config|
   # config.active_record.schema_format = :sql
 
   # Activate observers that should always be running
-  config.active_record.observers = [:user_observer, :repository_observer]
+  config.active_record.observers = [
+      :user_observer, 
+      :repository_observer, 
+      :merge_request_observer
+  ]
 
   # Make Active Record use UTC-base instead of local time
   config.active_record.default_timezone = :utc

--- a/config/routes.rb
+++ b/config/routes.rb
@@ -38,6 +38,7 @@ ActionController::Routing::Routes.draw do |map|
     }, :path_name => "repos") do |repo|
       repo.resources :committers, :name_prefix => nil, :collection => {:auto_complete_for_user_login => :post}
       repo.resources :comments
+      repo.resources :merge_requests, :member => { :resolve => :put }
       repo.commit_comment "comments/commit/:sha", :controller => "comments", 
         :action => "commit", :conditions => { :method => :get }
       

--- /dev/null
+++ b/db/migrate/021_create_merge_requests.rb
@@ -0,0 +1,21 @@
+class CreateMergeRequests < ActiveRecord::Migration
+  def self.up
+    create_table :merge_requests do |t|
+      t.integer   :user_id
+      t.integer   :source_repository_id
+      t.integer   :target_repository_id
+      t.text      :proposal
+      t.string    :sha_snapshot
+      t.integer   :status, :default => 0
+      t.timestamps
+    end
+    add_index :merge_requests, :user_id
+    add_index :merge_requests, :source_repository_id
+    add_index :merge_requests, :target_repository_id
+    add_index :merge_requests, :status
+  end
+
+  def self.down
+    drop_table :merge_requests
+  end
+end

--- a/db/schema.rb
+++ b/db/schema.rb
@@ -9,7 +9,7 @@
 #
 # It's strongly recommended to check this file into your version control system.
 
-ActiveRecord::Schema.define(:version => 20) do
+ActiveRecord::Schema.define(:version => 21) do
 
   create_table "comments", :force => true do |t|
     t.integer  "user_id",       :null => false
@@ -37,6 +37,22 @@ ActiveRecord::Schema.define(:version => 20) do
   add_index "committerships", ["repository_id"], :name => "index_permissions_on_repository_id"
   add_index "committerships", ["user_id"], :name => "index_permissions_on_user_id"
 
+  create_table "merge_requests", :force => true do |t|
+    t.integer  "user_id"
+    t.integer  "source_repository_id"
+    t.integer  "target_repository_id"
+    t.text     "proposal"
+    t.string   "sha_snapshot"
+    t.integer  "status",               :default => 0
+    t.datetime "created_at"
+    t.datetime "updated_at"
+  end
+
+  add_index "merge_requests", ["user_id"], :name => "index_merge_requests_on_user_id"
+  add_index "merge_requests", ["source_repository_id"], :name => "index_merge_requests_on_source_repository_id"
+  add_index "merge_requests", ["target_repository_id"], :name => "index_merge_requests_on_target_repository_id"
+  add_index "merge_requests", ["status"], :name => "index_merge_requests_on_status"
+
   create_table "projects", :force => true do |t|
     t.string   "title"
     t.text     "description"