Re: [PATCH 4/4] blame: test the -b option, use blank oid for boundary commits.

[Jeff King <peff@peff.net>]

On Mon, May 25, 2020 at 10:57:51PM +0100, Philip Oakley wrote:

> The sed script removes the last hex digit from boundary commit oids
> '^hexx msg' -> '^hex  msg' until all leading hex's are gone, finally
> removing the boundary commit marker.

Thanks for documenting this, as the sed was rather hard to read:

> +test_expect_success 'test -b option, blank oid for boundary commits' '
> +	git blame -b branch1.. -- file >actual &&
> +	git blame branch1.. -- file >full &&
> +	sed -e "/^\^/{
> +		:loop;
> +		s/^\(\^[0-9a-f]*\)[0-9a-f] \(.*\)/\1  \2/g;
> +		tloop;
> +		s/^\^/ /;
> +	}" full >expected &&

I wonder if we can make it simpler.

In perl I'd probably just replace the whole string with the equivalent
number of spaces, like:

  perl -pe 's/^\^\S+/" " x length($&)/e'

but I suppose some would consider that pretty magical, too. It might be
simpler still to just avoid testing leading whitespace:

   sed 's/^\^[0-9a-f]* *//' <full >expected &&
   sed 's/^ *//' <actual >actual.stripped &&
   test_cmp expected actual.stripped

but perhaps the indentation is a useful part of what we're testing.

-Peff