Merge remote-tracking branch 'upstream/master' into pipeline-emails

* upstream/master: (237 commits)
  Grapify boards API
  Add test, fix merge error
  Use local assigns to get the dropdown title
  Updated issuable dropdown titles
  Added safety check for formatted values
  Minor style improvement
  Fixed conflict and corrected teaspoon test
  Rename method in test
  Moved ci_status environments logic to new action ci_envrionments_status and set up frontend polling
  Refactor ci_status on MergeRequestController
  Fix indenting error in HAML
  Show what time ago a MR was deployed
  Fixed missing links
  Fixed missing links
  Refactor merge requests revisions
  Add link to update docs for source installations
  Grapify todos API
  Link to review apps example from docs
  fix grafana_configuration.md move link
  Do not run before_script, artifacts, cache in trigger_docs job
  ...

1 files changed, 31 insertions, 2 deletions

diff --git a/lib/extracts_path.rb b/lib/extracts_path.rb
index a4558d157c0..e4d996a3fb6 100644
--- a/lib/extracts_path.rb
+++ b/lib/extracts_path.rb
@@ -52,8 +52,7 @@ module ExtractsPath
       # Append a trailing slash if we only get a ref and no file path
       id += '/' unless id.ends_with?('/')
 
-      valid_refs = @project.repository.ref_names
-      valid_refs.select! { |v| id.start_with?("#{v}/") }
+      valid_refs = ref_names.select { |v| id.start_with?("#{v}/") }
 
       if valid_refs.length == 0
         # No exact ref match, so just try our best
@@ -74,6 +73,19 @@ module ExtractsPath
     pair
   end
 
+  # If we have an ID of 'foo.atom', and the controller provides Atom and HTML
+  # formats, then we have to check if the request was for the Atom version of
+  # the ID without the '.atom' suffix, or the HTML version of the ID including
+  # the suffix. We only check this if the version including the suffix doesn't
+  # match, so it is possible to create a branch which has an unroutable Atom
+  # feed.
+  def extract_ref_without_atom(id)
+    id_without_atom = id.sub(/\.atom$/, '')
+    valid_refs = ref_names.select { |v| "#{id_without_atom}/".start_with?("#{v}/") }
+
+    valid_refs.max_by(&:length)
+  end
+
   # Assigns common instance variables for views working with Git tree-ish objects
   #
   # Assignments are:
@@ -86,6 +98,10 @@ module ExtractsPath
   # If the :id parameter appears to be requesting a specific response format,
   # that will be handled as well.
   #
+  # If there is no path and the ref doesn't exist in the repo, try to resolve
+  # the ref without an '.atom' suffix. If _that_ ref is found, set the request's
+  # format to Atom manually.
+  #
   # Automatically renders `not_found!` if a valid tree path could not be
   # resolved (e.g., when a user inserts an invalid path or ref).
   def assign_ref_vars
@@ -103,6 +119,13 @@ module ExtractsPath
       @commit = @repo.commit(@options[:extended_sha1])
     end
 
+    if @path.empty? && !@commit
+      @id = @ref = extract_ref_without_atom(@id)
+      @commit = @repo.commit(@ref)
+
+      request.format = :atom if @commit
+    end
+
     raise InvalidPathError unless @commit
 
     @hex_path = Digest::SHA1.hexdigest(@path)
@@ -125,4 +148,10 @@ module ExtractsPath
     id += "/" + params[:path] unless params[:path].blank?
     id
   end
+
+  def ref_names
+    return [] unless @project
+
+    @ref_names ||= @project.repository.ref_names
+  end
 end