As discussed on
699ec5a87f (commitcomment-156776835),
to properly support scrolling long content in Ratatui for a sequence of
cells, we need to:
* take the `Vec<Line>` for each cell
* using the wrapping logic we want to use at render time, compute the
_effective line count_ using `Paragraph::line_count()` (see
`wrapped_line_count_for_cell()` in this PR)
* sum up the effective line count to compute the height of the area
being scrolled
* given a `scroll_position: usize`, index into the list of "effective
lines" and accumulate the appropriate `Vec<Line>` for the cells that
should be displayed
* take that `Vec<Line>` to create a `Paragraph` and use the same
line-wrapping policy that was used in `wrapped_line_count_for_cell()`
* display the resulting `Paragraph` and use the accounting to display a
scrollbar with the appropriate thumb size and offset without having to
render the `Vec<Line>` for the full history
With this change, lines wrap as I expect and everything appears to
redraw correctly as I resize my terminal!
0b9ef93da5