When tracking a hashtag on a stream, having passed the ‘language’ property, I noticed that I was not receiving any tweets in which all words were hashtags (i.e. “#This #is #an #example”), even if one of the hashtags was the one I was actually tracking.
Later, when I removed the language property from the object passed as second attribute to the stream method, that same tweet, if published again, was perfectly tracked.
So, removing the language property from the query resolves the issue of the missing tweets: the deal is, Twitteris not capable of detecting the language of a Tweet if every word it has is a hashtag, son it returns the ‘lang’ property of the tweet as “und” (undefined).
Anyway, if you are trying to track a hashtag, and you suspect the users of that hashtag might write tweets with all words being hashtags, or in any case, tweets which language might be impossible to detect by twitter… just don’t include the “language” property as a value for filtering when tracking.
Thanks for the great work!