bug#28792: 26.0.60; Deleting to a custom trash directory in Dired gives error

[Drew Adams]

What Noam said.

I think the problem with the error message is not that
it was composed from multiple pieces.  It is that after
those pieces have been joined the result is not a
normal message.

In particular, there should be some punctuation or other
separation between the piece that says that the thing is
not a regular file ("Non-regular file" or whatever) and
the piece that says what is not regular about it ("Is a
directory" or whatever).

This message is not normal (it is confusing):

 (file-error Non-regular file Is a directory /the/file/)

This message is better (though not ideal):

 file-error: Non-regular file: Is a directory, /the/file/