Initial commit

app/models/release_number.rb

@@ -0,0 +1,25 @@
+class ReleaseNumber
+  attr_reader :release
+
+  def initialize(release)
+    @release = release
+  end
+
+  def value
+    (release_ids.index(release.id) || 0) + 1
+  end
+
+  private
+
+  def project
+    release.project
+  end
+
+  def release_ids
+    project.public_send(release_type).order(Arel.sql("COALESCE(signed_at, created_at) ASC")).ids
+  end
+
+  def release_type
+    release.model_name.plural
+  end
+end