Fix project lookup. Show error if project transfer fails

app/assets/javascripts/main.js.coffee

@@ -7,6 +7,12 @@ window.slugify = (text) ->
 window.ajaxGet = (url) ->
   $.ajax({type: "GET", url: url, dataType: "script"})
 
+window.errorMessage = (message) ->
+  ehtml = $("<p>")
+  ehtml.addClass("error_message")
+  ehtml.html(message)
+  ehtml
+
 # Disable button if text field is empty
 window.disableButtonIfEmptyField = (field_selector, button_selector) ->
   field = $(field_selector)

app/controllers/projects_controller.rb

@@ -46,6 +46,10 @@ class ProjectsController < ProjectResourceController
         format.js
       end
     end
+
+  rescue Project::TransferError => ex
+    @error = ex
+    render :update_failed
   end
 
   def show

app/models/project.rb

@@ -26,6 +26,8 @@ class Project < ActiveRecord::Base
   include Authority
   include Team
 
+  class TransferError < StandardError; end
+
   attr_accessible :name, :path, :description, :default_branch, :issues_enabled,
                   :wall_enabled, :merge_requests_enabled, :wiki_enabled, as: [:default, :admin]
 
@@ -101,7 +103,7 @@ class Project < ActiveRecord::Base
         namespace_id = Namespace.find_by_path(id.first).id
         where(namespace_id: namespace_id).find_by_path(id.last)
       else
-        find_by_path(id)
+        where(path: id, namespace_id: nil).last
       end
     end
 
@@ -270,12 +272,18 @@ class Project < ActiveRecord::Base
                    self.path
                  end
 
+      if Project.where(path: self.path, namespace_id: new_namespace.try(:id)).present?
+        raise TransferError.new("Project with same path in target namespace already exists")
+      end
+
       Gitlab::ProjectMover.new(self, old_dir, new_dir).execute
 
       git_host.move_repository(old_repo, self)
 
       save!
     end
+  rescue Gitlab::ProjectMover::ProjectMoveError => ex
+    raise TransferError.new(ex.message)
   end
 
   def name_with_namespace

app/views/projects/_form.html.haml

@@ -22,7 +22,7 @@
         %span Namespace
       .controls
         - if can? current_user, :change_namespace, @project
-          = f.select :namespace_id, namespaces_options(@project.namespace_id), {prompt: 'Choose a project namespace'}, {class: 'chosen'}
+          = f.select :namespace_id, namespaces_options(@project.namespace_id || Namespace::global_id), {prompt: 'Choose a project namespace'}, {class: 'chosen'}
            
           %span.cred Be careful. Changing project namespace can have unintended side effects
         - else

app/views/projects/update_failed.js.haml

@@ -0,0 +1,2 @@
+:plain
+  $(".save-project-loader").replaceWith(errorMessage('#{escape_javascript(@error.message)}'));