DEV: Capture error output in specs

lib/docker_manager/upgrader.rb

@@ -135,7 +135,7 @@ def upgrade
     status("failed")
 
     ["Docker Manager: FAILED TO UPGRADE", ex.inspect, ex.backtrace.join("\n")].each do |message|
-      STDERR.puts(message)
+      warn(message)
       log(message)
     end
 

spec/lib/docker_manager/upgrader_spec.rb

@@ -80,23 +80,29 @@
       let(:workers) { [2001] }
 
       it "raises an error" do
-        expect { upgrader.upgrade }.to raise_error("Not enough workers")
+        expect {
+          expect { upgrader.upgrade }.to output(/FAILED TO UPGRADE/).to_stderr
+        }.to raise_error("Not enough workers")
       end
     end
 
     context "when launcher process is missing" do
       let(:launcher_pid) { 0 }
 
       it "raises an error" do
-        expect { upgrader.upgrade }.to raise_error("No Pitchfork master or launcher")
+        expect {
+          expect { upgrader.upgrade }.to output(/FAILED TO UPGRADE/).to_stderr
+        }.to raise_error("No Pitchfork master or launcher")
       end
     end
 
     context "when master process is missing" do
       let(:master_pid) { 0 }
 
       it "raises an error" do
-        expect { upgrader.upgrade }.to raise_error("No Pitchfork master or launcher")
+        expect {
+          expect { upgrader.upgrade }.to output(/FAILED TO UPGRADE/).to_stderr
+        }.to raise_error("No Pitchfork master or launcher")
       end
     end
 
@@ -238,17 +244,23 @@
       end
 
       it "sets status to failed" do
-        expect { upgrader.upgrade }.to raise_error(RuntimeError)
+        expect {
+          expect { upgrader.upgrade }.to output(/FAILED TO UPGRADE/).to_stderr
+        }.to raise_error(RuntimeError)
         expect(upgrader.last_status).to eq("failed")
       end
 
       it "stops upgrading for all repos" do
-        expect { upgrader.upgrade }.to raise_error(RuntimeError)
+        expect {
+          expect { upgrader.upgrade }.to output(/FAILED TO UPGRADE/).to_stderr
+        }.to raise_error(RuntimeError)
         expect(repo).to have_received(:stop_upgrading)
       end
 
       it "scales workers back up" do
-        expect { upgrader.upgrade }.to raise_error(RuntimeError)
+        expect {
+          expect { upgrader.upgrade }.to output(/FAILED TO UPGRADE/).to_stderr
+        }.to raise_error(RuntimeError)
         expect(upgrader.web_server).to have_received(:scale_up_workers).with(2)
       end
     end