Port `read_cross_project` ability from EE

1 files changed, 29 insertions, 1 deletions

diff --git a/app/models/ability.rb b/app/models/ability.rb
index 0b6bcbde5d9..6dae49f38dc 100644
--- a/app/models/ability.rb
+++ b/app/models/ability.rb
@@ -22,12 +22,30 @@ class Ability
     #
     # issues - The issues to reduce down to those readable by the user.
     # user - The User for which to check the issues
-    def issues_readable_by_user(issues, user = nil)
+    # filters - A hash of abilities and filters to apply if the user lacks this
+    #           ability
+    def issues_readable_by_user(issues, user = nil, filters: {})
+      issues = apply_filters_if_needed(issues, user, filters)
+
       DeclarativePolicy.user_scope do
         issues.select { |issue| issue.visible_to_user?(user) }
       end
     end
 
+    # Returns an Array of MergeRequests that can be read by the given user.
+    #
+    # merge_requests - MRs out of which to collect mr's readable by the user.
+    # user - The User for which to check the merge_requests
+    # filters - A hash of abilities and filters to apply if the user lacks this
+    #           ability
+    def merge_requests_readable_by_user(merge_requests, user = nil, filters: {})
+      merge_requests = apply_filters_if_needed(merge_requests, user, filters)
+
+      DeclarativePolicy.user_scope do
+        merge_requests.select { |mr| allowed?(user, :read_merge_request, mr) }
+      end
+    end
+
     def can_edit_note?(user, note)
       allowed?(user, :edit_note, note)
     end
@@ -53,5 +71,15 @@ class Ability
       cache = RequestStore.active? ? RequestStore : {}
       DeclarativePolicy.policy_for(user, subject, cache: cache)
     end
+
+    private
+
+    def apply_filters_if_needed(elements, user, filters)
+      filters.each do |ability, filter|
+        elements = filter.call(elements) unless allowed?(user, ability)
+      end
+
+      elements
+    end
   end
 end