ZIm/crates/vim/src/normal/scroll.rs
Conrad Irwin e3c0e93e46 Fix cursor adjustment on scroll
Fixes: zed-industries/community#1929

Also preserves visual modes correctly.
2023-08-18 11:23:43 -06:00

116 lines
3.8 KiB
Rust

use crate::Vim;
use editor::{
display_map::ToDisplayPoint,
scroll::{scroll_amount::ScrollAmount, VERTICAL_SCROLL_MARGIN},
DisplayPoint, Editor,
};
use gpui::{actions, AppContext, ViewContext};
use language::Bias;
use workspace::Workspace;
actions!(
vim,
[LineUp, LineDown, ScrollUp, ScrollDown, PageUp, PageDown,]
);
pub fn init(cx: &mut AppContext) {
cx.add_action(|_: &mut Workspace, _: &LineDown, cx| {
scroll(cx, |c| ScrollAmount::Line(c.unwrap_or(1.)))
});
cx.add_action(|_: &mut Workspace, _: &LineUp, cx| {
scroll(cx, |c| ScrollAmount::Line(-c.unwrap_or(1.)))
});
cx.add_action(|_: &mut Workspace, _: &PageDown, cx| {
scroll(cx, |c| ScrollAmount::Page(c.unwrap_or(1.)))
});
cx.add_action(|_: &mut Workspace, _: &PageUp, cx| {
scroll(cx, |c| ScrollAmount::Page(-c.unwrap_or(1.)))
});
cx.add_action(|_: &mut Workspace, _: &ScrollDown, cx| {
scroll(cx, |c| {
if let Some(c) = c {
ScrollAmount::Line(c)
} else {
ScrollAmount::Page(0.5)
}
})
});
cx.add_action(|_: &mut Workspace, _: &ScrollUp, cx| {
scroll(cx, |c| {
if let Some(c) = c {
ScrollAmount::Line(-c)
} else {
ScrollAmount::Page(-0.5)
}
})
});
}
fn scroll(cx: &mut ViewContext<Workspace>, by: fn(c: Option<f32>) -> ScrollAmount) {
Vim::update(cx, |vim, cx| {
let amount = by(vim.pop_number_operator(cx).map(|c| c as f32));
vim.update_active_editor(cx, |editor, cx| scroll_editor(editor, &amount, cx));
})
}
fn scroll_editor(editor: &mut Editor, amount: &ScrollAmount, cx: &mut ViewContext<Editor>) {
let should_move_cursor = editor.newest_selection_on_screen(cx).is_eq();
editor.scroll_screen(amount, cx);
if should_move_cursor {
let visible_rows = if let Some(visible_rows) = editor.visible_line_count() {
visible_rows as u32
} else {
return;
};
let top_anchor = editor.scroll_manager.anchor().anchor;
editor.change_selections(None, cx, |s| {
s.move_heads_with(|map, head, goal| {
let top = top_anchor.to_display_point(map);
let min_row = top.row() + VERTICAL_SCROLL_MARGIN as u32;
let max_row = top.row() + visible_rows - VERTICAL_SCROLL_MARGIN as u32 - 1;
let new_head = if head.row() < min_row {
map.clip_point(DisplayPoint::new(min_row, head.column()), Bias::Left)
} else if head.row() > max_row {
map.clip_point(DisplayPoint::new(max_row, head.column()), Bias::Left)
} else {
head
};
(new_head, goal)
})
});
}
}
#[cfg(test)]
mod test {
use crate::{state::Mode, test::VimTestContext};
use gpui::geometry::vector::vec2f;
use indoc::indoc;
#[gpui::test]
async fn test_scroll(cx: &mut gpui::TestAppContext) {
let mut cx = VimTestContext::new(cx, true).await;
cx.set_state(indoc! {"ˇa\nb\nc\nd\ne\n"}, Mode::Normal);
cx.update_editor(|editor, cx| {
assert_eq!(editor.snapshot(cx).scroll_position(), vec2f(0., 0.))
});
cx.simulate_keystrokes(["ctrl-e"]);
cx.update_editor(|editor, cx| {
assert_eq!(editor.snapshot(cx).scroll_position(), vec2f(0., 1.))
});
cx.simulate_keystrokes(["2", "ctrl-e"]);
cx.update_editor(|editor, cx| {
assert_eq!(editor.snapshot(cx).scroll_position(), vec2f(0., 3.))
});
cx.simulate_keystrokes(["ctrl-y"]);
cx.update_editor(|editor, cx| {
assert_eq!(editor.snapshot(cx).scroll_position(), vec2f(0., 2.))
});
}
}