Per what choroba said (perhaps privately) regarding the source document, I did a hexdump of the source document, and found that vi was appending, but not presenting, a newline in that data set.

If I explicitly added a newline, there were two terminal newline characters in hexdump.

Mystery solved, sort of, but that looks like a bug in vim. I always trusted it before.

In reply to Re^5: hackerrank.com question by writch
in thread hackerrank.com question by writch

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