Create failcase for deploying the same code twice

CHANGELOG.md

@@ -2,6 +2,8 @@
 
 # Master
 
+- Add failcase for cache busting
+
 - Correct ftp to https in vendored file
 - Warn for Django 1.11 approaching EOL, provide link to roadmap
 

test/run-deps

@@ -65,6 +65,16 @@ testPylibmc() {
   assertCapturedSuccess
 }
 
+testDeployingTwiceUsesTheCache() {
+  compile "pythonDefault"
+  assertNotCaptured "Installing collected packages:"
+  assertCapturedSuccess
+  compile "pythonDefault"
+  assertCaptured "Requirement already satisfied:"
+  assertNotCaptured "Installing collected packages:"
+  assertCapturedSuccess
+}
+
 pushd $(dirname 0) >/dev/null
 popd >/dev/null