1 files changed, 47 insertions, 37 deletions
diff --git a/lib/extracts_ref.rb b/lib/extracts_ref.rb
index 346ed6b6f60..5ef2d888550 100644
--- a/lib/extracts_ref.rb
+++ b/lib/extracts_ref.rb
@@ -40,43 +40,12 @@ module ExtractsRef
   # Returns an Array where the first value is the tree-ish and the second is the
   # path
   def extract_ref(id)
-    pair = ['', '']
-
-    return pair unless repository_container
-
-    if id =~ /^(\h{40})(.+)/
-      # If the ref appears to be a SHA, we're done, just split the string
-      pair = $~.captures
-    else
-      # Otherwise, attempt to detect the ref using a list of the repository_container's
-      # branches and tags
-
-      # Append a trailing slash if we only get a ref and no file path
-      unless id.ends_with?('/')
-        id = [id, '/'].join
-      end
-
-      valid_refs = ref_names.select { |v| id.start_with?("#{v}/") }
-
-      if valid_refs.empty?
-        # No exact ref match, so just try our best
-        pair = id.match(%r{([^/]+)(.*)}).captures
-      else
-        # There is a distinct possibility that multiple refs prefix the ID.
-        # Use the longest match to maximize the chance that we have the
-        # right ref.
-        best_match = valid_refs.max_by(&:length)
-        # Partition the string into the ref and the path, ignoring the empty first value
-        pair = id.partition(best_match)[1..-1]
-      end
-    end
-
-    pair[0] = pair[0].strip
-
-    # Remove ending slashes from path
-    pair[1].gsub!(%r{^/|/$}, '')
-
-    pair
+    pair = extract_raw_ref(id)
+
+    [
+      pair[0].strip,
+      pair[1].delete_prefix('/').delete_suffix('/')
+    ]
   end
 
   # Assigns common instance variables for views working with Git tree-ish objects
@@ -109,6 +78,47 @@ module ExtractsRef
 
   private
 
+  def extract_raw_ref(id)
+    return ['', ''] unless repository_container
+
+    # If the ref appears to be a SHA, we're done, just split the string
+    return $~.captures if id =~ /^(\h{40})(.+)/
+
+    # No slash means we must have a ref and no path
+    return [id, ''] unless id.include?('/')
+
+    # Otherwise, attempt to detect the ref using a list of the
+    # repository_container's branches and tags
+
+    # Append a trailing slash if we only get a ref and no file path
+    id = [id, '/'].join unless id.ends_with?('/')
+    first_path_segment, rest = id.split('/', 2)
+
+    return [first_path_segment, rest] if use_first_path_segment?(first_path_segment)
+
+    valid_refs = ref_names.select { |v| id.start_with?("#{v}/") }
+
+    # No exact ref match, so just try our best
+    return id.match(%r{([^/]+)(.*)}).captures if valid_refs.empty?
+
+    # There is a distinct possibility that multiple refs prefix the ID.
+    # Use the longest match to maximize the chance that we have the
+    # right ref.
+    best_match = valid_refs.max_by(&:length)
+
+    # Partition the string into the ref and the path, ignoring the empty first value
+    id.partition(best_match)[1..-1]
+  end
+
+  def use_first_path_segment?(ref)
+    return false unless ::Feature.enabled?(:extracts_path_optimization)
+    return false unless repository_container
+    return false if repository_container.repository.has_ambiguous_refs?
+
+    repository_container.repository.branch_names_include?(ref) ||
+      repository_container.repository.tag_names_include?(ref)
+  end
+
   # overridden in subclasses, do not remove
   def get_id
     id = [params[:id] || params[:ref]]