util.datamapper: Don't include empty unwrapped arrays
Since there is no way to distinguish an empty such array from a
zero-length array. Dropping it seems like the least annoying thing to
do.
The Prosody project is open to contributions (see HACKERS file), but is
maintained daily by:
- Matthew Wild (mail: matthew [at] prosody.im)
- Waqas Hussain (mail: waqas [at] prosody.im)
- Kim Alvefur (mail: zash [at] prosody.im)
You can reach us collectively by email: developers [at] prosody.im
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