scroll_delta contains how much the top line of a window moved since the
last time win_viewport was emitted. It is expected to be used to
implement smooth scrolling. For this purpose it only counts "virtual" or
"displayed" so folds should count as one line. Because of this it
adds extra information that cannot be computed from the topline
parameter.
Fixes#19227
In non-multigrid UI the only change is that the returned height now
excludes winbar, and this is compatible with Vim.
In multigrid UI this means the return value of these functions now
reflect the space available for buffer lines in a window.
No change in nvim_win_get_height() and nvim_win_get_width().
Currently, multigrid mouse drag positions are handled incorrectly if the
drag event is not in the top left grid. Fix this by not adjusting the
position of the event in jump_to_mouse.
related: #15091
When create tab, win_hide sent to new tab and new tab's previous tab.
So, if created tab that not next tab (eg. $tabnew cmd),
send win_hide to not current tab, and fixed this.
It is perfectly fine and expected to detach from the screen just by
the UI disconnecting from nvim or exiting nvim. Just keep detach() in
screen_basic_spec, to get some coverage of the detach method itself.
This avoids hang on failure in many situations (though one could argue
that detach() should be "fast", or at least "as fast as resize",
which works in press-return already).
Never use detach() just to change the size of the screen, try_resize()
method exists for that specifically.
Callers can instead specify `args_rm={'--headless'}`.
TODO: should `nvim_argv` have "--headless" by default? Need to inspect
some uses of spawn(nvim_argv) ...
