Create framework for build prerequisites

Introduces the concept of Prerequisites for a CI build.
If a build has unmet prerequisites it will go through the
:preparing state before being made available to a runner.

There are no actual prerequisites yet, so current
behaviour is unchanged.

1 files changed, 6 insertions, 0 deletions

diff --git a/spec/models/commit_status_spec.rb b/spec/models/commit_status_spec.rb
index 1d241bf6000..e2b7f5c6ee2 100644
--- a/spec/models/commit_status_spec.rb
+++ b/spec/models/commit_status_spec.rb
@@ -489,6 +489,12 @@ describe CommitStatus do
 
       it { is_expected.to be_script_failure }
     end
+
+    context 'when failure_reason is unmet_prerequisites' do
+      let(:reason) { :unmet_prerequisites }
+
+      it { is_expected.to be_unmet_prerequisites }
+    end
   end
 
   describe 'ensure stage assignment' do