On 06/12/2018 18:11, Stefan Beller wrote:
On Thu, Dec 6, 2018 at 6:58 AM Phillip Wood <phillip.wood@xxxxxxxxxxxx> wrote:
So is there some "must be at least two consecutive lines" condition for
not-plain, or is something else going on here?
To be considered a block has to have 20 alphanumeric characters - see
commit f0b8fb6e59 ("diff: define block by number of alphanumeric chars",
2017-08-15). This stops things like random '}' lines being marked as
moved on their own.
This is spot on.
All but the "plain" mode use the concept of "blocks" of code
(there is even one mode called "blocks", which adds to the confusion).
It might be better to use some kind of frequency
information (a bit like python's difflib junk parameter) instead so that
(fairly) unique short lines also get marked properly.
Yes that is what I was initially thinking about. However to have good
information, you'd need to index a whole lot (the whole repository,
i.e. all text blobs in existence?) to get an accurate picture of frequency
information, which I'd prefer to call entropy as I come from a background
familiar with https://en.wikipedia.org/wiki/Information_theory, I am not
sure where 'frequency information' comes from -- it sounds like the
same concept.
Of course it is too expensive to run an operation O(repository size)
just for this diff, so maybe we could get away with some smaller
corpus to build up this information on what is sufficient for coloring.
When only looking at the given diff, I would imagine that each line
would not carry a whole lot of information as its characters occur
rather frequently compared to the rest of the diff.
I was thinking of using lines rather than characters as the unit of
information (if that's the right phrase). I was hoping that seeing how
often a given line occurs within the set of files being diffed would be
good enough to tell is if it is an "interesting" move or not. In the
mean time I wonder if decreasing the block limit to 10 alphanumeric
characters would be enough to prevent too much noise in the output
without suppressing matches that it would be useful to highlight.
Best Wishes
Phillip
Best,
Stefan
