3 files changed, 67 insertions, 11 deletions

diff --git a/app/helpers/gitlab_markdown_helper.rb b/app/helpers/gitlab_markdown_helper.rb
index 7bcc011fd5f..d89f7b4a28d 100644
--- a/app/helpers/gitlab_markdown_helper.rb
+++ b/app/helpers/gitlab_markdown_helper.rb
@@ -135,15 +135,25 @@ module GitlabMarkdownHelper
     end
   end
 
+  # Returns the text necessary to reference `entity` across projects
+  #
+  # project - Project to reference
+  # entity  - Object that responds to `to_reference`
+  #
+  # Examples:
+  #
+  #   cross_project_reference(project, project.issues.first)
+  #   # => 'namespace1/project1#123'
+  #
+  #   cross_project_reference(project, project.merge_requests.first)
+  #   # => 'namespace1/project1!345'
+  #
+  # Returns a String
   def cross_project_reference(project, entity)
-    path = project.path_with_namespace
-
-    if entity.kind_of?(Issue)
-      [path, entity.iid].join('#')
-    elsif entity.kind_of?(MergeRequest)
-      [path, entity.iid].join('!')
+    if entity.respond_to?(:to_reference)
+      "#{project.to_reference}#{entity.to_reference}"
     else
-      raise 'Not supported type'
+      ''
     end
   end
 end
diff --git a/app/helpers/labels_helper.rb b/app/helpers/labels_helper.rb
index 8272c177d59..8036303851b 100644
--- a/app/helpers/labels_helper.rb
+++ b/app/helpers/labels_helper.rb
@@ -1,6 +1,44 @@
 module LabelsHelper
   include ActionView::Helpers::TagHelper
 
+  # Link to a Label
+  #
+  # label   - Label object to link to
+  # project - Project object which will be used as the context for the label's
+  #           link. If omitted, defaults to `@project`, or the label's own
+  #           project.
+  # block   - An optional block that will be passed to `link_to`, forming the
+  #           body of the link element. If omitted, defaults to
+  #           `render_colored_label`.
+  #
+  # Examples:
+  #
+  #   # Allow the generated link to use the label's own project
+  #   link_to_label(label)
+  #
+  #   # Force the generated link to use @project
+  #   @project = Project.first
+  #   link_to_label(label)
+  #
+  #   # Force the generated link to use a provided project
+  #   link_to_label(label, project: Project.last)
+  #
+  #   # Customize link body with a block
+  #   link_to_label(label) { "My Custom Label Text" }
+  #
+  # Returns a String
+  def link_to_label(label, project: nil, &block)
+    project ||= @project || label.project
+    link = namespace_project_issues_path(project.namespace, project,
+                                         label_name: label.name)
+
+    if block_given?
+      link_to link, &block
+    else
+      link_to render_colored_label(label), link
+    end
+  end
+
   def project_label_names
     @project.labels.pluck(:title)
   end
diff --git a/app/helpers/projects_helper.rb b/app/helpers/projects_helper.rb
index 96d2606f1a1..f8df39d236a 100644
--- a/app/helpers/projects_helper.rb
+++ b/app/helpers/projects_helper.rb
@@ -148,7 +148,7 @@ module ProjectsHelper
       nav_tabs << [:files, :commits, :network, :graphs]
     end
 
-    if project.repo_exists? && project.merge_requests_enabled
+    if project.repo_exists? && can?(current_user, :read_merge_request, project)
       nav_tabs << :merge_requests
     end
 
@@ -156,11 +156,19 @@ module ProjectsHelper
       nav_tabs << :settings
     end
 
-    [:issues, :wiki, :snippets].each do |feature|
-      nav_tabs << feature if project.send :"#{feature}_enabled"
+    if can?(current_user, :read_issue, project)
+      nav_tabs << :issues
     end
 
-    if project.issues_enabled || project.merge_requests_enabled
+    if can?(current_user, :read_wiki, project)
+      nav_tabs << :wiki
+    end
+
+    if can?(current_user, :read_project_snippet, project)
+      nav_tabs << :snippets
+    end
+
+    if can?(current_user, :read_milestone, project)
       nav_tabs << [:milestones, :labels]
     end