Automatically fork a project when not allowed to edit a file.

29 files changed, 452 insertions, 273 deletions

diff --git a/app/assets/javascripts/blob/blob_file_dropzone.js.coffee b/app/assets/javascripts/blob/blob_file_dropzone.js.coffee
index 195f8b11e5d..9df932817f6 100644
--- a/app/assets/javascripts/blob/blob_file_dropzone.js.coffee
+++ b/app/assets/javascripts/blob/blob_file_dropzone.js.coffee
@@ -35,7 +35,7 @@ class @BlobFileDropzone
           return
 
         this.on 'sending', (file, xhr, formData) ->
-          formData.append('new_branch', form.find('.js-new-branch').val())
+          formData.append('target_branch', form.find('.js-target-branch').val())
           formData.append('create_merge_request', form.find('.js-create-merge-request').val())
           formData.append('commit_message', form.find('.js-commit-message').val())
           return
diff --git a/app/assets/javascripts/new_commit_form.js.coffee b/app/assets/javascripts/new_commit_form.js.coffee
index 3c7b776155f..03f0f51acfa 100644
--- a/app/assets/javascripts/new_commit_form.js.coffee
+++ b/app/assets/javascripts/new_commit_form.js.coffee
@@ -1,6 +1,6 @@
 class @NewCommitForm
   constructor: (form) ->
-    @newBranch = form.find('.js-new-branch')
+    @newBranch = form.find('.js-target-branch')
     @originalBranch = form.find('.js-original-branch')
     @createMergeRequest = form.find('.js-create-merge-request')
     @createMergeRequestContainer = form.find('.js-create-merge-request-container')
diff --git a/app/controllers/concerns/creates_commit.rb b/app/controllers/concerns/creates_commit.rb
new file mode 100644
index 00000000000..62127a09081
--- /dev/null
+++ b/app/controllers/concerns/creates_commit.rb
@@ -0,0 +1,103 @@
+module CreatesCommit
+  extend ActiveSupport::Concern
+
+  def create_commit(service, success_path:, failure_path:, failure_view: nil, success_notice: nil)
+    set_commit_variables
+
+    commit_params = @commit_params.merge(
+      source_project: @project,
+      source_branch: @ref,
+      target_branch: @target_branch
+    )
+
+    result = service.new(@tree_edit_project, current_user, commit_params).execute
+
+    if result[:status] == :success
+      flash[:notice] = success_notice || "Your changes have been successfully committed."
+
+      if create_merge_request?
+        success_path = new_merge_request_path
+        target = different_project? ? "project" : "branch"
+        flash[:notice] << " You can now submit a merge request to get this change into the original #{target}."
+      end
+
+      respond_to do |format|
+        format.html { redirect_to success_path }
+        format.json { render json: { message: "success", filePath: success_path } }
+      end
+    else
+      flash[:alert] = result[:message]
+      respond_to do |format|
+        format.html do
+          if failure_view
+            render failure_view
+          else
+            redirect_to failure_path
+          end
+        end
+        format.json { render json: { message: "failed", filePath: failure_path } }
+      end
+    end
+  end
+
+  def authorize_edit_tree!
+    return if can?(current_user, :push_code, project)
+    return if current_user && current_user.already_forked?(project)
+
+    access_denied!
+  end
+
+  private
+
+  def new_merge_request_path
+    new_namespace_project_merge_request_path(
+      @mr_source_project.namespace,
+      @mr_source_project,
+      merge_request: {
+        source_project_id: @mr_source_project.id,
+        target_project_id: @mr_target_project.id,
+        source_branch: @mr_source_branch,
+        target_branch: @mr_target_branch
+      }
+    )
+  end
+
+  def different_project?
+    @mr_source_project != @mr_target_project
+  end
+
+  def different_branch?
+    @mr_source_branch != @mr_target_branch || different_project?
+  end
+
+  def create_merge_request?
+    params[:create_merge_request].present? && different_branch?
+  end
+
+  def set_commit_variables
+    @mr_source_branch = @target_branch
+
+    if can?(current_user, :push_code, @project)
+      # Edit file in this project
+      @tree_edit_project = @project
+      @mr_source_project = @project
+
+      if @project.forked?
+        # Merge request from this project to fork origin
+        @mr_target_project = @project.forked_from_project
+        @mr_target_branch = @mr_target_project.repository.root_ref
+      else
+        # Merge request to this project
+        @mr_target_project = @project
+        @mr_target_branch = @ref
+      end
+    else
+      # Edit file in fork
+      @tree_edit_project = current_user.fork_of(@project)
+      # Merge request from fork to this project
+      @mr_source_project = @tree_edit_project
+      @mr_target_project = @project
+      @mr_target_branch = @mr_target_project.repository.root_ref
+    end
+  end
+end
diff --git a/app/controllers/concerns/creates_merge_request_for_commit.rb b/app/controllers/concerns/creates_merge_request_for_commit.rb
deleted file mode 100644
index c7527822158..00000000000
--- a/app/controllers/concerns/creates_merge_request_for_commit.rb
+++ /dev/null
@@ -1,28 +0,0 @@
-module CreatesMergeRequestForCommit
-  extend ActiveSupport::Concern
-
-  def new_merge_request_path
-    if @project.forked?
-      target_project = @project.forked_from_project || @project
-      target_branch = target_project.repository.root_ref
-    else
-      target_project = @project
-      target_branch = @ref
-    end
-
-    new_namespace_project_merge_request_path(
-      @project.namespace,
-      @project,
-      merge_request: {
-        source_project_id: @project.id,
-        target_project_id: target_project.id,
-        source_branch: @new_branch,
-        target_branch: target_branch
-      }
-    )
-  end
-
-  def create_merge_request?
-    params[:create_merge_request] && @new_branch != @ref
-  end
-end
diff --git a/app/controllers/projects/blob_controller.rb b/app/controllers/projects/blob_controller.rb
index 62163682936..c56a3497bb2 100644
--- a/app/controllers/projects/blob_controller.rb
+++ b/app/controllers/projects/blob_controller.rb
@@ -1,7 +1,7 @@
 # Controller for viewing a file's blame
 class Projects::BlobController < Projects::ApplicationController
   include ExtractsPath
-  include CreatesMergeRequestForCommit
+  include CreatesCommit
   include ActionView::Helpers::SanitizeHelper
 
   # Raised when given an invalid file path
@@ -9,21 +9,21 @@ class Projects::BlobController < Projects::ApplicationController
 
   before_action :require_non_empty_project, except: [:new, :create]
   before_action :authorize_download_code!
-  before_action :authorize_push_code!, only: [:destroy, :create]
+  before_action :authorize_edit_tree!, only: [:new, :create, :edit, :update, :destroy]
   before_action :assign_blob_vars
   before_action :commit, except: [:new, :create]
   before_action :blob, except: [:new, :create]
   before_action :from_merge_request, only: [:edit, :update]
   before_action :require_branch_head, only: [:edit, :update]
   before_action :editor_variables, except: [:show, :preview, :diff]
-  before_action :after_edit_path, only: [:edit, :update]
 
   def new
     commit unless @repository.empty?
   end
 
   def create
-    create_commit(Files::CreateService, success_path: after_create_path,
+    create_commit(Files::CreateService, success_notice: "The file has been successfully created.",
+                                        success_path: namespace_project_blob_path(@project.namespace, @project, File.join(@target_branch, @file_path)),
                                         failure_view: :new,
                                         failure_path: namespace_project_new_blob_path(@project.namespace, @project, @ref))
   end
@@ -36,6 +36,14 @@ class Projects::BlobController < Projects::ApplicationController
   end
 
   def update
+    after_edit_path =
+      if from_merge_request && @target_branch == @ref
+        diffs_namespace_project_merge_request_path(from_merge_request.target_project.namespace, from_merge_request.target_project, from_merge_request) +
+          "#file-path-#{hexdigest(@path)}"
+      else
+        namespace_project_blob_path(@project.namespace, @project, File.join(@target_branch, @path))
+      end
+
     create_commit(Files::UpdateService, success_path: after_edit_path,
                                         failure_view: :edit,
                                         failure_path: namespace_project_blob_path(@project.namespace, @project, @id))
@@ -50,15 +58,10 @@ class Projects::BlobController < Projects::ApplicationController
   end
 
   def destroy
-    result = Files::DeleteService.new(@project, current_user, @commit_params).execute
-
-    if result[:status] == :success
-      flash[:notice] = "Your changes have been successfully committed"
-      redirect_to after_destroy_path
-    else
-      flash[:alert] = result[:message]
-      render :show
-    end
+    create_commit(Files::DeleteService, success_notice: "The file has been successfully deleted.",
+                                        success_path: namespace_project_tree_path(@project.namespace, @project, @target_branch),
+                                        failure_view: :show,
+                                        failure_path: namespace_project_blob_path(@project.namespace, @project, @id))
   end
 
   def diff
@@ -108,74 +111,13 @@ class Projects::BlobController < Projects::ApplicationController
     render_404
   end
 
-  def create_commit(service, success_path:, failure_view:, failure_path:)
-    result = service.new(@project, current_user, @commit_params).execute
-
-    if result[:status] == :success
-      flash[:notice] = "Your changes have been successfully committed"
-      respond_to do |format|
-        format.html { redirect_to success_path }
-        format.json { render json: { message: "success", filePath: success_path } }
-      end
-    else
-      flash[:alert] = result[:message]
-      respond_to do |format|
-        format.html { render failure_view }
-        format.json { render json: { message: "failed", filePath: failure_path } }
-      end
-    end
-  end
-
-  def after_create_path
-    @after_create_path ||=
-      if create_merge_request?
-        new_merge_request_path
-      else
-        namespace_project_blob_path(@project.namespace, @project, File.join(@new_branch, @file_path))
-      end
-  end
-
-  def after_edit_path
-    @after_edit_path ||=
-      if create_merge_request?
-        new_merge_request_path
-      elsif from_merge_request && @new_branch == @ref
-        diffs_namespace_project_merge_request_path(from_merge_request.target_project.namespace, from_merge_request.target_project, from_merge_request) +
-          "#file-path-#{hexdigest(@path)}"
-      else
-        namespace_project_blob_path(@project.namespace, @project, File.join(@new_branch, @path))
-      end
-  end
-
-  def after_destroy_path
-    @after_destroy_path ||=
-      if create_merge_request?
-        new_merge_request_path
-      else
-        namespace_project_tree_path(@project.namespace, @project, @new_branch)
-      end
-  end
-
   def from_merge_request
     # If blob edit was initiated from merge request page
     @from_merge_request ||= MergeRequest.find_by(id: params[:from_merge_request_id])
   end
 
-  def sanitized_new_branch_name
-    sanitize(strip_tags(params[:new_branch]))
-  end
-
   def editor_variables
-    @current_branch = @ref
-
-    @new_branch =
-      if params[:new_branch].present?
-        sanitized_new_branch_name
-      elsif ::Gitlab::GitAccess.new(current_user, @project).can_push_to_branch?(@ref)
-        @ref
-      else
-        @repository.next_patch_branch
-      end
+    @target_branch = params[:target_branch]
 
     @file_path =
       if action_name.to_s == 'create'
@@ -194,8 +136,6 @@ class Projects::BlobController < Projects::ApplicationController
 
     @commit_params = {
       file_path: @file_path,
-      current_branch: @current_branch,
-      target_branch: @new_branch,
       commit_message: params[:commit_message],
       file_content: params[:content],
       file_content_encoding: params[:encoding]
diff --git a/app/controllers/projects/forks_controller.rb b/app/controllers/projects/forks_controller.rb
index 8a785076bb7..51181b8042e 100644
--- a/app/controllers/projects/forks_controller.rb
+++ b/app/controllers/projects/forks_controller.rb
@@ -13,16 +13,25 @@ class Projects::ForksController < Projects::ApplicationController
     @forked_project = ::Projects::ForkService.new(project, current_user, namespace: namespace).execute
 
     if @forked_project.saved? && @forked_project.forked?
+      continue_params[:notice] ||= "The project was successfully forked."
+
       if @forked_project.import_in_progress?
-        redirect_to namespace_project_import_path(@forked_project.namespace, @forked_project)
+        redirect_to namespace_project_import_path(@forked_project.namespace, @forked_project, continue: continue_params)
       else
-        redirect_to(
-          namespace_project_path(@forked_project.namespace, @forked_project),
-          notice: 'Project was successfully forked.'
-        )
+        if continue_params
+          redirect_to continue_params[:to], notice: continue_params[:notice]
+        else
+          redirect_to namespace_project_path(@forked_project.namespace, @forked_project)
+        end
       end
     else
       render :error
     end
   end
+
+  private
+
+  def continue_params
+    params[:continue].permit(:to, :notice, :notice_now)
+  end
 end
diff --git a/app/controllers/projects/imports_controller.rb b/app/controllers/projects/imports_controller.rb
index fb8788f0818..e9c9edd3a3c 100644
--- a/app/controllers/projects/imports_controller.rb
+++ b/app/controllers/projects/imports_controller.rb
@@ -1,7 +1,7 @@
 class Projects::ImportsController < Projects::ApplicationController
   # Authorize
   before_action :authorize_admin_project!
-  before_action :require_no_repo
+  before_action :require_no_repo, except: :show
   before_action :redirect_if_progress, except: :show
 
   def new
@@ -24,21 +24,31 @@ class Projects::ImportsController < Projects::ApplicationController
   end
 
   def show
-    unless @project.import_in_progress?
-      if @project.import_finished?
-        redirect_to(project_path(@project)) and return
+    if @project.repository_exists? || @project.import_finished?
+      if continue_params
+        redirect_to continue_params[:to], notice: continue_params[:notice]
       else
-        redirect_to(new_namespace_project_import_path(@project.namespace,
-                                                      @project)) and return
+        redirect_to project_path(@project)
       end
+    elsif @project.import_failed?
+      redirect_to new_namespace_project_import_path(@project.namespace, @project)
+    else
+      if continue_params && continue_params[:notice_now]
+        flash.now[:notice] = continue_params[:notice_now]
+      end
+      # Render
     end
   end
 
   private
 
+  def continue_params
+    @continue_params ||= params[:continue].permit(:to, :notice, :notice_now)
+  end
+
   def require_no_repo
     if @project.repository_exists? && !@project.import_in_progress?
-      redirect_to(namespace_project_path(@project.namespace, @project)) and return
+      redirect_to(namespace_project_path(@project.namespace, @project))
     end
   end
 
diff --git a/app/controllers/projects/tree_controller.rb b/app/controllers/projects/tree_controller.rb
index 8f272ad1281..4f78bde2d2d 100644
--- a/app/controllers/projects/tree_controller.rb
+++ b/app/controllers/projects/tree_controller.rb
@@ -1,14 +1,14 @@
 # Controller for viewing a repository's file structure
 class Projects::TreeController < Projects::ApplicationController
   include ExtractsPath
-  include CreatesMergeRequestForCommit
+  include CreatesCommit
   include ActionView::Helpers::SanitizeHelper
 
   before_action :require_non_empty_project, except: [:new, :create]
   before_action :assign_ref_vars
   before_action :assign_dir_vars, only: [:create_dir]
   before_action :authorize_download_code!
-  before_action :authorize_push_code!, only: [:create_dir]
+  before_action :authorize_edit_tree!, only: [:create_dir]
 
   def show
     return render_404 unless @repository.commit(@ref)
@@ -34,44 +34,20 @@ class Projects::TreeController < Projects::ApplicationController
   def create_dir
     return render_404 unless @commit_params.values.all?
 
-    begin
-      result = Files::CreateDirService.new(@project, current_user, @commit_params).execute
-      message = result[:message]
-    rescue => e
-      message = e.to_s
-    end
-
-    if result && result[:status] == :success
-      flash[:notice] = "The directory has been successfully created"
-      respond_to do |format|
-        format.html { redirect_to after_create_dir_path }
-      end
-    else
-      flash[:alert] = message
-      respond_to do |format|
-        format.html { redirect_to namespace_project_blob_path(@project.namespace, @project, @new_branch) }
-      end
-    end
+    create_commit(Files::CreateDirService,  success_notice: "The directory has been successfully created.",
+                                            success_path: namespace_project_blob_path(@project.namespace, @project, File.join(@target_branch, @dir_name)),
+                                            failure_path: namespace_project_tree_path(@project.namespace, @project, @ref))
   end
 
   private
 
   def assign_dir_vars
-    @new_branch = params[:new_branch].present? ? sanitize(strip_tags(params[:new_branch])) : @ref
+    @target_branch = params[:target_branch]
+
     @dir_name = File.join(@path, params[:dir_name])
     @commit_params = {
       file_path: @dir_name,
-      current_branch: @ref,
-      target_branch: @new_branch,
       commit_message: params[:commit_message],
     }
   end
-
-  def after_create_dir_path
-    if create_merge_request?
-      new_merge_request_path
-    else
-      namespace_project_blob_path(@project.namespace, @project, File.join(@new_branch, @dir_name))
-    end
-  end
 end
diff --git a/app/helpers/blob_helper.rb b/app/helpers/blob_helper.rb
index 68e5d5be600..81b1f34cdf8 100644
--- a/app/helpers/blob_helper.rb
+++ b/app/helpers/blob_helper.rb
@@ -22,32 +22,92 @@ module BlobHelper
     %w(credits changelog news copying copyright license authors)
   end
 
-  def edit_blob_link(project, ref, path, options = {})
-    blob =
-      begin
-        project.repository.blob_at(ref, path)
-      rescue
-        nil
-      end
-
-    return unless blob && blob.text? && blob_editable?(blob)
-
-    text = 'Edit'
-    after = options[:after] || ''
+  def edit_blob_link(project = @project, ref = @ref, path = @path, options = {})
+    return unless current_user
+
+    blob = project.repository.blob_at(ref, path) rescue nil
+
+    return unless blob && blob_text_editable?(blob)
+
     from_mr = options[:from_merge_request_id]
     link_opts = {}
     link_opts[:from_merge_request_id] = from_mr if from_mr
-    cls = 'btn btn-small'
-    link_to(text,
-            namespace_project_edit_blob_path(project.namespace, project,
-                                             tree_join(ref, path),
-                                             link_opts),
-            class: cls
-           ) + after.html_safe
+
+    edit_path = namespace_project_edit_blob_path(project.namespace, project,
+                                     tree_join(ref, path),
+                                     link_opts)
+
+    if !on_top_of_branch?
+      button_tag "Edit", class: "btn btn-default disabled has_tooltip", title: "You can only edit files when you are on a branch", data: {container: 'body'}
+    elsif can_edit_blob?(blob)
+      link_to "Edit", edit_path, class: 'btn btn-small'
+    elsif can?(current_user, :fork_project, project)
+      continue_params = {
+        to:     edit_path,
+        notice: edit_in_new_fork_notice,
+        notice_now: edit_in_new_fork_notice_now
+      }
+      fork_path = namespace_project_fork_path(project.namespace, project, namespace_key:  current_user.namespace.id,
+                                                                          continue:       continue_params)
+
+      link_to "Edit", fork_path, class: 'btn btn-small', method: :post
+    end
+  end
+
+  def modify_file_link(project = @project, ref = @ref, path = @path, label:, action:, btn_class:, modal_type:)
+    return unless current_user
+
+    blob = project.repository.blob_at(ref, path) rescue nil
+
+    return unless blob
+
+    if !on_top_of_branch?
+      button_tag label, class: "btn btn-#{btn_class} disabled has_tooltip", title: "You can only #{action} files when you are on a branch", data: {container: 'body'}
+    elsif can_edit_blob?(blob)
+      button_tag label, class: "btn btn-#{btn_class}", 'data-target' => "#modal-#{modal_type}-blob", 'data-toggle' => 'modal'
+    elsif can?(current_user, :fork_project, project)
+      continue_params = {
+        to:     request.fullpath,
+        notice: edit_in_new_fork_notice + " Try to #{action} this file again.",
+        notice_now: edit_in_new_fork_notice_now
+      }
+      fork_path = namespace_project_fork_path(project.namespace, project, namespace_key:  current_user.namespace.id,
+                                                                          continue:       continue_params)
+
+      link_to label, fork_path, class: "btn btn-#{btn_class}", method: :post
+    end
+  end
+
+  def replace_blob_link(project = @project, ref = @ref, path = @path)
+    modify_file_link(
+      project,
+      ref,
+      path,
+      label:      "Replace",
+      action:     "replace",
+      btn_class:  "default",
+      modal_type: "upload"
+    )
+  end
+
+  def delete_blob_link(project = @project, ref = @ref, path = @path)
+    modify_file_link(
+      project,
+      ref,
+      path,
+      label:      "Delete",
+      action:     "delete",
+      btn_class:  "remove",
+      modal_type: "remove"
+    )
+  end
+
+  def blob_text_editable?(blob)
+    blob.text? && !blob.lfs_pointer?
   end
 
-  def blob_editable?(blob, project = @project, ref = @ref)
-    !blob.lfs_pointer? && allowed_tree_edit?(project, ref)
+  def can_edit_blob?(blob, project = @project, ref = @ref)
+    !blob.lfs_pointer? && can_edit_tree?(project, ref)
   end
 
   def leave_edit_message
diff --git a/app/helpers/tree_helper.rb b/app/helpers/tree_helper.rb
index f448dd0ab61..2ad7c80dae0 100644
--- a/app/helpers/tree_helper.rb
+++ b/app/helpers/tree_helper.rb
@@ -50,24 +50,49 @@ module TreeHelper
     project.repository.branch_names.include?(ref)
   end
 
-  def allowed_tree_edit?(project = nil, ref = nil)
+  def can_edit_tree?(project = nil, ref = nil)
     project ||= @project
     ref ||= @ref
+
     return false unless on_top_of_branch?(project, ref)
 
-    can?(current_user, :push_code, project)
+    can?(current_user, :push_code, project) ||
+      (current_user && current_user.already_forked?(project))
   end
 
   def tree_edit_branch(project = @project, ref = @ref)
-    if allowed_tree_edit?(project, ref)
-      if can_push_branch?(project, ref)
-        ref
-      else
-        project.repository.next_patch_branch
-      end
+    return unless can_edit_tree?(project, ref)
+
+    if can_push_branch?(project, ref)
+      ref
+    else
+      project = tree_edit_project(project)
+      project.repository.next_patch_branch
+    end
+  end
+
+  def tree_edit_project(project = @project)
+    if can?(current_user, :push_code, project)
+      project
+    elsif current_user && current_user.already_forked?(project)
+      current_user.fork_of(project)
     end
   end
 
+  def edit_in_new_fork_notice_now
+    "You're not allowed to make changes to this project directly." +
+      " A fork of this project is being created that you can make changes in, so you can submit a merge request."
+  end
+
+  def edit_in_new_fork_notice
+    "You're not allowed to make changes to this project directly." +
+      " A fork of this project has been created that you can make changes in, so you can submit a merge request."
+  end
+
+  def commit_in_fork_help
+    "A new branch will be created in your fork and a new merge request will be started."
+  end
+
   def tree_breadcrumbs(tree, max_links = 2)
     if @path.present?
       part_path = ""
diff --git a/app/models/repository.rb b/app/models/repository.rb
index 2c25f4ce451..9f688e3b45b 100644
--- a/app/models/repository.rb
+++ b/app/models/repository.rb
@@ -592,47 +592,54 @@ class Repository
     Gitlab::Popen.popen(args, path_to_repo)
   end
 
-  def commit_with_hooks(current_user, branch)
-    oldrev = Gitlab::Git::BLANK_SHA
-    ref = Gitlab::Git::BRANCH_REF_PREFIX + branch
-    was_empty = empty?
-
-    # Create temporary ref
+  def with_tmp_ref(oldrev = nil)
     random_string = SecureRandom.hex
     tmp_ref = "refs/tmp/#{random_string}/head"
 
-    unless was_empty
-      oldrev = find_branch(branch).target
+    if oldrev && !Gitlab::Git.blank_ref?(oldrev)
       rugged.references.create(tmp_ref, oldrev)
     end
 
     # Make commit in tmp ref
-    newrev = yield(tmp_ref)
+    yield(tmp_ref)
+  ensure
+    rugged.references.delete(tmp_ref) rescue nil
+  end
+
+  def commit_with_hooks(current_user, branch)
+    oldrev = Gitlab::Git::BLANK_SHA
+    ref = Gitlab::Git::BRANCH_REF_PREFIX + branch
+    was_empty = empty?
 
-    unless newrev
-      raise CommitError.new('Failed to create commit')
+    unless was_empty
+      oldrev = find_branch(branch).target
     end
 
-    GitHooksService.new.execute(current_user, path_to_repo, oldrev, newrev, ref) do
-      if was_empty
-        # Create branch
-        rugged.references.create(ref, newrev)
-      else
-        # Update head
-        current_head = find_branch(branch).target
+    with_tmp_ref(oldrev) do |tmp_ref|
+      # Make commit in tmp ref
+      newrev = yield(tmp_ref)
+
+      unless newrev
+        raise CommitError.new('Failed to create commit')
+      end
 
-        # Make sure target branch was not changed during pre-receive hook
-        if current_head == oldrev
-          rugged.references.update(ref, newrev)
+      GitHooksService.new.execute(current_user, path_to_repo, oldrev, newrev, ref) do
+        if was_empty
+          # Create branch
+          rugged.references.create(ref, newrev)
         else
-          raise CommitError.new('Commit was rejected because branch received new push')
+          # Update head
+          current_head = find_branch(branch).target
+
+          # Make sure target branch was not changed during pre-receive hook
+          if current_head == oldrev
+            rugged.references.update(ref, newrev)
+          else
+            raise CommitError.new('Commit was rejected because branch received new push')
+          end
         end
       end
     end
-  rescue GitHooksService::PreReceiveError
-    # Remove tmp ref and return error to user
-    rugged.references.delete(tmp_ref)
-    raise
   end
 
   private
diff --git a/app/services/create_branch_service.rb b/app/services/create_branch_service.rb
index de18f3bc556..84e141f5fd8 100644
--- a/app/services/create_branch_service.rb
+++ b/app/services/create_branch_service.rb
@@ -1,7 +1,7 @@
 require_relative 'base_service'
 
 class CreateBranchService < BaseService
-  def execute(branch_name, ref)
+  def execute(branch_name, ref, source_project: @project)
     valid_branch = Gitlab::GitRefValidator.validate(branch_name)
     if valid_branch == false
       return error('Branch name invalid')
@@ -13,7 +13,20 @@ class CreateBranchService < BaseService
       return error('Branch already exists')
     end
 
-    new_branch = repository.add_branch(current_user, branch_name, ref)
+    new_branch = nil
+    if source_project != @project
+      repository.with_tmp_ref do |tmp_ref|
+        repository.fetch_ref(
+          source_project.repository.path_to_repo,
+          "refs/heads/#{ref}",
+          tmp_ref
+        )
+
+        new_branch = repository.add_branch(current_user, branch_name, tmp_ref)
+      end
+    else
+      new_branch = repository.add_branch(current_user, branch_name, ref)
+    end
 
     if new_branch
       push_data = build_push_data(project, current_user, new_branch)
diff --git a/app/services/files/base_service.rb b/app/services/files/base_service.rb
index 9a67b160940..0326a8823e9 100644
--- a/app/services/files/base_service.rb
+++ b/app/services/files/base_service.rb
@@ -3,8 +3,10 @@ module Files
     class ValidationError < StandardError; end
 
     def execute
-      @current_branch = params[:current_branch]
+      @source_project = params[:source_project] || @project
+      @source_branch = params[:source_branch]
       @target_branch  = params[:target_branch]
+
       @commit_message = params[:commit_message]
       @file_path      = params[:file_path]
       @file_content   = if params[:file_content_encoding] == 'base64'
@@ -16,8 +18,8 @@ module Files
       # Validate parameters
       validate
 
-      # Create new branch if it different from current_branch
-      if @target_branch != @current_branch
+      # Create new branch if it different from source_branch
+      if different_branch?
         create_target_branch
       end
 
@@ -26,18 +28,14 @@ module Files
       else
         error("Something went wrong. Your changes were not committed")
       end
-    rescue Repository::CommitError, GitHooksService::PreReceiveError, ValidationError => ex
+    rescue Repository::CommitError, Gitlab::Git::Repository::InvalidBlobName, GitHooksService::PreReceiveError, ValidationError => ex
       error(ex.message)
     end
 
     private
 
-    def current_branch
-      @current_branch ||= params[:current_branch]
-    end
-
-    def target_branch
-      @target_branch ||= params[:target_branch]
+    def different_branch?
+      @source_branch != @target_branch || @source_project != @project
     end
 
     def raise_error(message)
@@ -52,11 +50,11 @@ module Files
       end
 
       unless project.empty_repo?
-        unless repository.branch_names.include?(@current_branch)
+        unless @source_project.repository.branch_names.include?(@source_branch)
           raise_error("You can only create or edit files when you are on a branch")
         end
 
-        if @current_branch != @target_branch
+        if different_branch?
           if repository.branch_names.include?(@target_branch)
             raise_error("Branch with such name already exists. You need to switch to this branch in order to make changes")
           end
@@ -65,10 +63,10 @@ module Files
     end
 
     def create_target_branch
-      result = CreateBranchService.new(project, current_user).execute(@target_branch, @current_branch)
+      result = CreateBranchService.new(project, current_user).execute(@target_branch, @source_branch, source_project: @source_project)
 
       unless result[:status] == :success
-        raise_error("Something went wrong when we tried to create #{@target_branch} for you")
+        raise_error("Something went wrong when we tried to create #{@target_branch} for you: #{result[:message]}")
       end
     end
   end
diff --git a/app/services/files/create_service.rb b/app/services/files/create_service.rb
index 2348920cc58..e4cde4a2fd8 100644
--- a/app/services/files/create_service.rb
+++ b/app/services/files/create_service.rb
@@ -26,7 +26,7 @@ module Files
       unless project.empty_repo?
         @file_path.slice!(0) if @file_path.start_with?('/')
 
-        blob = repository.blob_at_branch(@current_branch, @file_path)
+        blob = repository.blob_at_branch(@source_branch, @file_path)
 
         if blob
           raise_error("Your changes could not be committed because a file with the same name already exists")
diff --git a/app/views/projects/_commit_button.html.haml b/app/views/projects/_commit_button.html.haml
index 2fd3d9e1be4..640612ca433 100644
--- a/app/views/projects/_commit_button.html.haml
+++ b/app/views/projects/_commit_button.html.haml
@@ -2,3 +2,7 @@
   = button_tag 'Commit Changes', class: 'btn commit-btn js-commit-button btn-create'
   = link_to 'Cancel', cancel_path,
             class: 'btn btn-cancel', data: {confirm: leave_edit_message}
+
+  - unless can?(current_user, :push_code, @project)
+    .inline.prepend-left-10
+      = commit_in_fork_help
diff --git a/app/views/projects/blob/_actions.html.haml b/app/views/projects/blob/_actions.html.haml
index b1df8d19938..caefd911a2a 100644
--- a/app/views/projects/blob/_actions.html.haml
+++ b/app/views/projects/blob/_actions.html.haml
@@ -14,13 +14,8 @@
   = link_to 'Permalink', namespace_project_blob_path(@project.namespace, @project,
       tree_join(@commit.sha, @path)), class: 'btn btn-sm'
 
-- if blob_editable?(@blob)
+- if current_user
   .btn-group{ role: "group" }
-    = edit_blob_link(@project, @ref, @path)
-    %button.btn.btn-default{ 'data-target' => '#modal-upload-blob', 'data-toggle' => 'modal' } Replace
-    %button.btn.btn-remove{ 'data-target' => '#modal-remove-blob', 'data-toggle' => 'modal' } Delete
-- elsif !on_top_of_branch?
-  .btn-group{ role: "group" }
-    %button.btn.btn-default.disabled.has_tooltip{title: "You can only edit files when you are on a branch.", data: {container: 'body'}} Edit
-    %button.btn.btn-default.disabled.has_tooltip{title: "You can only replace files when you are on a branch.", data: {container: 'body'}} Replace
-    %button.btn.btn-remove.disabled.has_tooltip{title: "You can only delete files when you are on a branch.", data: {container: 'body'}} Delete
+    = edit_blob_link
+    = replace_blob_link
+    = delete_blob_link
diff --git a/app/views/projects/blob/_new_dir.html.haml b/app/views/projects/blob/_new_dir.html.haml
index fc6c9f5fd09..084608bbba3 100644
--- a/app/views/projects/blob/_new_dir.html.haml
+++ b/app/views/projects/blob/_new_dir.html.haml
@@ -17,5 +17,9 @@
             = submit_tag "Create directory", class: 'btn btn-create'
             = link_to "Cancel", '#', class: "btn btn-cancel", "data-dismiss" => "modal"
 
+            - unless can?(current_user, :push_code, @project)
+              .inline.prepend-left-10
+                = commit_in_fork_help
+
 :javascript
   new NewCommitForm($('.js-create-dir-form'))
diff --git a/app/views/projects/blob/_upload.html.haml b/app/views/projects/blob/_upload.html.haml
index ecc90a30e78..676924dc6ca 100644
--- a/app/views/projects/blob/_upload.html.haml
+++ b/app/views/projects/blob/_upload.html.haml
@@ -20,6 +20,11 @@
             = button_tag button_title, class: 'btn btn-small btn-create btn-upload-file', id: 'submit-all'
             = link_to "Cancel", '#', class: "btn btn-cancel", "data-dismiss" => "modal"
 
+            - unless can?(current_user, :push_code, @project)
+              .inline.prepend-left-10
+                = commit_in_fork_help
+
+
 :javascript
   disableButtonIfEmptyField($('.js-upload-blob-form').find('.js-commit-message'), '.btn-upload-file');
   new BlobFileDropzone($('.js-upload-blob-form'), '#{method}');
diff --git a/app/views/projects/blob/edit.html.haml b/app/views/projects/blob/edit.html.haml
index a47fe7ede80..09fa148b129 100644
--- a/app/views/projects/blob/edit.html.haml
+++ b/app/views/projects/blob/edit.html.haml
@@ -20,7 +20,7 @@
     = hidden_field_tag 'last_commit', @last_commit
     = hidden_field_tag 'content', '', id: "file-content"
     = hidden_field_tag 'from_merge_request_id', params[:from_merge_request_id]
-    = render 'projects/commit_button', ref: @ref, cancel_path: @after_edit_path
+    = render 'projects/commit_button', ref: @ref, cancel_path: namespace_project_blob_path(@project.namespace, @project, @id)
 
 :javascript
   blob = new EditBlob(gon.relative_url_root + "#{Gitlab::Application.config.assets.prefix}", "#{@blob.language.try(:ace_mode)}")
diff --git a/app/views/projects/blob/show.html.haml b/app/views/projects/blob/show.html.haml
index 3f8d11ed8c8..6988039b6c7 100644
--- a/app/views/projects/blob/show.html.haml
+++ b/app/views/projects/blob/show.html.haml
@@ -6,7 +6,7 @@
 %div#tree-holder.tree-holder
   = render 'blob', blob: @blob
 
-- if blob_editable?(@blob)
+- if can_edit_blob?(@blob)
   = render 'projects/blob/remove'
 
   - title = "Replace #{@blob.name}"
diff --git a/app/views/projects/buttons/_dropdown.html.haml b/app/views/projects/buttons/_dropdown.html.haml
index b277b765b6b..1f639fecc30 100644
--- a/app/views/projects/buttons/_dropdown.html.haml
+++ b/app/views/projects/buttons/_dropdown.html.haml
@@ -18,10 +18,11 @@
           = link_to new_namespace_project_snippet_path(@project.namespace, @project) do
             = icon('file-text-o fw')
             New snippet
+
       - if can?(current_user, :push_code, @project)
         %li.divider
         %li
-          = link_to namespace_project_new_blob_path(@project.namespace, @project, @project.default_branch || 'master'), title: 'New file' do
+          = link_to namespace_project_new_blob_path(@project.namespace, @project, @project.default_branch || 'master') do
             = icon('file fw')
             New file
         %li
@@ -32,3 +33,20 @@
           = link_to new_namespace_project_tag_path(@project.namespace, @project) do
             = icon('tags fw')
             New tag
+      - elsif current_user && current_user.already_forked?(@project)
+        %li.divider
+        %li
+          = link_to namespace_project_new_blob_path(@project.namespace, @project, @project.default_branch || 'master') do
+            = icon('file fw')
+            New file
+      - elsif can?(current_user, :fork_project, @project)
+        %li.divider
+        %li
+          - continue_params = { to:         namespace_project_new_blob_path(@project.namespace, @project, @project.default_branch || 'master'),
+                                notice:     edit_in_new_fork_notice,
+                                notice_now: edit_in_new_fork_notice_now }
+          - fork_path = namespace_project_fork_path(@project.namespace, @project, namespace_key:  current_user.namespace.id,
+                                                                                  continue:       continue_params)
+          = link_to fork_path, method: :post do
+            = icon('file fw')
+            New file
diff --git a/app/views/projects/diffs/_file.html.haml b/app/views/projects/diffs/_file.html.haml
index 327e7d9245a..9c6d7b46429 100644
--- a/app/views/projects/diffs/_file.html.haml
+++ b/app/views/projects/diffs/_file.html.haml
@@ -32,7 +32,8 @@
         - if editable_diff?(diff_file)
           = edit_blob_link(@merge_request.source_project,
               @merge_request.source_branch, diff_file.new_path,
-              after: '&nbsp;', from_merge_request_id: @merge_request.id)
+              from_merge_request_id: @merge_request.id)
+          &nbsp;
 
         = view_file_btn(diff_commit.id, diff_file, project)
 
diff --git a/app/views/projects/forks/new.html.haml b/app/views/projects/forks/new.html.haml
index f0b0a11c04a..8a2c027a455 100644
--- a/app/views/projects/forks/new.html.haml
+++ b/app/views/projects/forks/new.html.haml
@@ -43,4 +43,3 @@
       %i.fa.fa-spinner.fa-spin
       Forking repository
     %p Please wait a moment, this page will automatically refresh when ready.
-
diff --git a/app/views/projects/tree/_tree_content.html.haml b/app/views/projects/tree/_tree_content.html.haml
index 1bc90edd8f0..1927883513a 100644
--- a/app/views/projects/tree/_tree_content.html.haml
+++ b/app/views/projects/tree/_tree_content.html.haml
@@ -29,7 +29,7 @@
   - if tree.readme
     = render "projects/tree/readme", readme: tree.readme
 
-- if allowed_tree_edit?
+- if can_edit_tree?
   = render 'projects/blob/upload', title: 'Upload New File', placeholder: 'Upload new file', button_title: 'Upload file', form_path: namespace_project_create_blob_path(@project.namespace, @project, @id), method: :post
   = render 'projects/blob/new_dir'
 
diff --git a/app/views/projects/tree/_tree_header.html.haml b/app/views/projects/tree/_tree_header.html.haml
index cefe33e581f..6167006f947 100644
--- a/app/views/projects/tree/_tree_header.html.haml
+++ b/app/views/projects/tree/_tree_header.html.haml
@@ -11,26 +11,60 @@
         = link_to truncate(title, length: 40), namespace_project_tree_path(@project.namespace, @project, path)
       - else
         = link_to title, '#'
-  - if allowed_tree_edit?
+
+  - if current_user
     %li
-      %span.dropdown
-        %a.dropdown-toggle.btn.btn-sm.add-to-tree{href: '#', "data-toggle" => "dropdown"}
+      - if !on_top_of_branch?
+        %span.btn.btn-sm.add-to-tree.disabled.has_tooltip{title: "You can only add files when you are on a branch", data: {container: 'body'}}
           = icon('plus')
-        %ul.dropdown-menu
-          %li
-            = link_to namespace_project_new_blob_path(@project.namespace, @project, @id), title: 'Create file', id: 'new-file-link' do
-              = icon('pencil fw')
-              Create file
-          %li
-            = link_to '#modal-upload-blob', { 'data-target' => '#modal-upload-blob', 'data-toggle' => 'modal'} do
-              = icon('file fw')
-              Upload file
-          %li.divider
-          %li
-            = link_to '#modal-create-new-dir', { 'data-target' => '#modal-create-new-dir', 'data-toggle' => 'modal'} do
-              = icon('folder fw')
-              New directory
-  - elsif !on_top_of_branch?
-    %li
-      %span.btn.btn-sm.add-to-tree.disabled.has_tooltip{title: "You can only add files when you are on a branch.", data: {container: 'body'}}
-        = icon('plus')
+      - elsif can_edit_tree?
+        %span.dropdown
+          %a.dropdown-toggle.btn.btn-sm.add-to-tree{href: '#', "data-toggle" => "dropdown"}
+            = icon('plus')
+          %ul.dropdown-menu
+            %li
+              = link_to namespace_project_new_blob_path(@project.namespace, @project, @id) do
+                = icon('pencil fw')
+                Create file
+            %li
+              = link_to '#modal-upload-blob', { 'data-target' => '#modal-upload-blob', 'data-toggle' => 'modal'} do
+                = icon('file fw')
+                Upload file
+            %li.divider
+            %li
+              = link_to '#modal-create-new-dir', { 'data-target' => '#modal-create-new-dir', 'data-toggle' => 'modal'} do
+                = icon('folder fw')
+                New directory
+      - elsif can?(current_user, :fork_project, @project)
+        %span.dropdown
+          %a.dropdown-toggle.btn.btn-sm.add-to-tree{href: '#', "data-toggle" => "dropdown"}
+            = icon('plus')
+          %ul.dropdown-menu
+            %li
+              - continue_params = { to:         namespace_project_new_blob_path(@project.namespace, @project, @id),
+                                    notice:     edit_in_new_fork_notice,
+                                    notice_now: edit_in_new_fork_notice_now }
+              - fork_path = namespace_project_fork_path(@project.namespace, @project, namespace_key:  current_user.namespace.id,
+                                                                                      continue:       continue_params)
+              = link_to fork_path, method: :post do
+                = icon('pencil fw')
+                Create file
+            %li
+              - continue_params = { to:         request.fullpath,
+                                    notice:     edit_in_new_fork_notice + " Try to upload a file again.",
+                                    notice_now: edit_in_new_fork_notice_now }
+              - fork_path = namespace_project_fork_path(@project.namespace, @project, namespace_key:  current_user.namespace.id,
+                                                                                      continue:       continue_params)
+              = link_to fork_path, method: :post do
+                = icon('file fw')
+                Upload file
+            %li.divider
+            %li
+              - continue_params = { to:         request.fullpath,
+                                    notice:     edit_in_new_fork_notice + " Try to create a new directory again.",
+                                    notice_now: edit_in_new_fork_notice_now }
+              - fork_path = namespace_project_fork_path(@project.namespace, @project, namespace_key:  current_user.namespace.id,
+                                                                                      continue:       continue_params)
+              = link_to fork_path, method: :post do
+                = icon('folder fw')
+                New directory
diff --git a/app/views/shared/_new_commit_form.html.haml b/app/views/shared/_new_commit_form.html.haml
index 111219f2064..0c8ac48bb58 100644
--- a/app/views/shared/_new_commit_form.html.haml
+++ b/app/views/shared/_new_commit_form.html.haml
@@ -1,16 +1,22 @@
 = render 'shared/commit_message_container', placeholder: placeholder
 
-- unless @project.empty_repo?
-  .form-group.branch
-    = label_tag 'new_branch', 'Target branch', class: 'control-label'
-    .col-sm-10
-      = text_field_tag 'new_branch', @new_branch || tree_edit_branch, required: true, class: "form-control js-new-branch"
+- if @project.empty_repo?
+  = hidden_field_tag 'target_branch', @ref
+- else
+  - if can?(current_user, :push_code, @project)
+    .form-group.branch
+      = label_tag 'target_branch', 'Target branch', class: 'control-label'
+      .col-sm-10
+        = text_field_tag 'target_branch', @target_branch || tree_edit_branch, required: true, class: "form-control js-target-branch"
 
-      .js-create-merge-request-container
-        .checkbox
-          - nonce = SecureRandom.hex
-          = label_tag "create_merge_request-#{nonce}" do
-            = check_box_tag 'create_merge_request', 1, true, class: 'js-create-merge-request', id: "create_merge_request-#{nonce}"
-            Start a <strong>new merge request</strong> with these changes
+        .js-create-merge-request-container
+          .checkbox
+            - nonce = SecureRandom.hex
+            = label_tag "create_merge_request-#{nonce}" do
+              = check_box_tag 'create_merge_request', 1, true, class: 'js-create-merge-request', id: "create_merge_request-#{nonce}"
+              Start a <strong>new merge request</strong> with these changes
+  - else
+    = hidden_field_tag 'target_branch', @target_branch || tree_edit_branch
+    = hidden_field_tag 'create_merge_request', 1
 
   = hidden_field_tag 'original_branch', @ref, class: 'js-original-branch'
diff --git a/features/steps/project/source/browse_files.rb b/features/steps/project/source/browse_files.rb
index 0c6df18ce2e..da8a07c2b4a 100644
--- a/features/steps/project/source/browse_files.rb
+++ b/features/steps/project/source/browse_files.rb
@@ -75,7 +75,7 @@ class Spinach::Features::ProjectSourceBrowseFiles < Spinach::FeatureSteps
   end
 
   step 'I fill the new branch name' do
-    fill_in :new_branch, with: 'new_branch_name', visible: true
+    fill_in :target_branch, with: 'new_branch_name', visible: true
   end
 
   step 'I fill the new file name with an illegal name' do
diff --git a/lib/api/files.rb b/lib/api/files.rb
index a7a768f8895..8ad2c1883c7 100644
--- a/lib/api/files.rb
+++ b/lib/api/files.rb
@@ -7,7 +7,7 @@ module API
       def commit_params(attrs)
         {
           file_path: attrs[:file_path],
-          current_branch: attrs[:branch_name],
+          source_branch: attrs[:branch_name],
           target_branch: attrs[:branch_name],
           commit_message: attrs[:commit_message],
           file_content: attrs[:content],
diff --git a/spec/controllers/projects/tree_controller_spec.rb b/spec/controllers/projects/tree_controller_spec.rb
index a474574c6e5..a4366e378c7 100644
--- a/spec/controllers/projects/tree_controller_spec.rb
+++ b/spec/controllers/projects/tree_controller_spec.rb
@@ -98,7 +98,7 @@ describe Projects::TreeController do
            project_id: project.to_param,
            id: 'master',
            dir_name: path,
-           new_branch: target_branch,
+           target_branch: target_branch,
            commit_message: 'Test commit message')
     end
 
@@ -109,7 +109,7 @@ describe Projects::TreeController do
       it 'redirects to the new directory' do
         expect(subject).
             to redirect_to("/#{project.path_with_namespace}/blob/#{target_branch}/#{path}")
-        expect(flash[:notice]).to eq('The directory has been successfully created')
+        expect(flash[:notice]).to eq('The directory has been successfully created.')
       end
     end