Re: [PATCH v6 10/13] convert: generate large test files only once

> >> +	git checkout -- test test.t test.i &&
> >> +
> >> +	mkdir generated-test-data &&
> >> +	for i in $(test_seq 1 $T0021_LARGE_FILE_SIZE)
> >> +	do
> >> +		RANDOM_STRING="$(test-genrandom end $i | tr -dc "A-Za-z0-9" )"
> >> +		ROT_RANDOM_STRING="$(echo $RANDOM_STRING | ./rot13.sh )"
> > 
> > In earlier iteration of loop with lower $i, what guarantees that
> > some bytes survive "tr -dc"?
> 
> Nothing really, good catch! The seed "end" produces as first character always a 
> "S" which would survive "tr -dc". However, that is clunky. I will always set "1"
> as first character in $RANDOM_STRING to mitigate the problem.

> > I do not quite get the point of this complexity.  You are using
> > exactly the same seed "end" every time, so in the first round you
> > have 1M of SP, letter '1', letter 'S' (from the genrandom), then
> > in the second round you have 1M of SP, letter '1', letter 'S' and
> > letter 'p' (the last two from the genrandom), and go on.  Is it
> > significant for the purpose of your test that the cruft inserted
> > between the repetition of 1M of SP gets longer by one byte but they
> > all share the same prefix (e.g. "1S", "1Sp", "1SpZ", "1SpZT",
> > ... are what you insert between a large run of spaces)?
> 
> The pktline packets have a constant size. If the cruft between 1M of SP 
> has a constant size as well then the generated packets for the test data
> would repeat themselves. That's why I increased the length after every 1M
> of SP.
> 
> However, I realized that this test complexity is not necessary. I'll
> simplify it in the next round.