I'm not a skilled UI designer, so I suspect there may be even better
options, but it's definitely already better than the raw ASCII "---" we
had before.
Put the line only at the beginning because it looks bad if the line
after the label is misaligned when labels don't have the same width
(e.g. "Remote" vs. "Local" in the divergence view).
The model<->view index conversions were derived from arrays that only
renderLines populated. That made them depend on the list having been
rendered (so a conversion before the first render ignored the non-model
items), and it made them go stale whenever the model changed after a
render: converting an index then returned a wrong result, and once the
model had grown past the last rendered length the conversion indexed a
too-short array and panicked (seen in cherry_pick under -race).
The conversion is a pure function of the current list length and the
current non-model items, and needs none of the rendered display strings.
Compute it directly and drop the cached arrays, so the result is always
consistent with the current model and no longer depends on rendering.
searchModelCommits converts every commit's index, and building the
non-model items can be O(len) mid-rebase, so it would now be quadratic;
snapshot the non-model items once via modelToViewIndexConverter instead
of rebuilding them per index.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
I have seen cases where during a rebase (two nonModelItems) all entries in
viewIndicesByModelIndex beyond the second nonModelItem were off by 4 rather than
2 as I would expect. The only explanation I have for this is that the function
was called concurrently.
Improve this by working on a local variable and only assign to self at the end;
this is not a real fix for the concurrency issue of course, but it makes it much
less likely to be a problem in practice.
