Add unit tests to ensure retention policy for non existing db is not created

CHANGELOG.md

@@ -36,6 +36,7 @@
 - [#5478](https://github.com/influxdata/influxdb/issues/5478): panic: interface conversion: interface is float64, not int64
 - [#5475](https://github.com/influxdata/influxdb/issues/5475): Ensure appropriate exit code returned for non-interactive use of CLI.
 - [#5479](https://github.com/influxdata/influxdb/issues/5479): Bringing up a node as a meta only node causes panic
+- [#5504](https://github.com/influxdata/influxdb/issues/5475): create retention policy on unexistant DB crash InfluxDB
 
 ## v0.9.6 [2015-12-09]
 

cmd/influxd/run/server_suite_test.go

@@ -378,6 +378,12 @@ func init() {
 				command: `DROP RETENTION POLICY rp1 ON mydatabase`,
 				exp:     `{"results":[{"error":"database not found: mydatabase"}]}`,
 			},
+			&Query{
+				name:    "Ensure retention policy for non existing db is not created",
+				command: `CREATE RETENTION POLICY rp0 ON nodb DURATION 1h REPLICATION 1`,
+				exp:     `{"results":[{"error":"database not found: nodb"}]}`,
+				once:    true,
+			},
 		},
 	}