MemoryTLESource._get_tle always returns something

[enritoomey]

MemoryTLESource._get_tle(...) always return some TLE as long as the cache is not empty. This is not a bug by itself, but when WSTLESource._get_tle(...) method calls it, it will always return the TLE in the cache no matter how old it is. I don't think this is the expected behaviour, nor that is useful in any case. There should be an extra parameter to make WSTLESource._get_tle(...) for another TLE if the closes cache tle is farther away from the requested epoch than desired. If WSTLESource._fetch_tle(...) does not return a newer TLE, the return that of the cache, with a warning message.

[astrojuanlu]

...I have been just hit by this. I totally agree, this is not useful. I declare it a bug.