Re: [RFC PATCH v5 2/4] add -p: select modified lines correctly

Phillip Wood [off-list ref] writes:

The code actually looks at the lines that are selected rather than
omitted. So in the example above it groups them as [1,2] (because they
are contiguous), [4],[5] (these are split because one is an insertion
and one a deletion) and [7]. It then sees that there are two groups of
deletions ([1,2],[4]) and two groups of insertions ([5],[7]) and so
pairs up the deletions in [12] with the insertion in [5] and likewise
with [4] and [7]. Lines 3 and 6 are never explicitly paired, although
they basically behave as if they were. One the insertions are all paired
up it walks over the list and creates a new hunk where the paired
insertions come immediately after their corresponding deletions,
unselected deletions are converted to context lines and unselected
additions are dropped.

Now, without that much explanation in help text, can an average end
user use the feature, specifically, understand the reason why the
tool says it cannot handle a particular set of selected lines, and
follow the workaround suggested by the tool to do it in two (or
more) batches?  That was the real question I was getting at.  I
haven't played with the feature long enough to answer that question.

quoted

quoted

Reported-by: Ævar Arnfjörð Bjarmason <redacted>

Is this fixing any bug?  I usually see "Reported-by" only for a
bugfix patch but this seems to be adding a new feature (and lack of
feature is usually not a bug).

I guess I meant that the previous series was effectively buggy as it
would give the wrong result for modified lines. I wanted to acknowledge
that Ævar spent some time testing it and pointed that out.

Ah, I see.  We generally throw these into "Helped-by", I'd think.

Thanks.