history.redo()

This commit is contained in:
Blaž Hrastnik 2020-10-05 16:12:36 +09:00
parent 8c7bc71ede
commit 04b1546634

View file

@ -1,16 +1,16 @@
use crate::{ChangeSet, Rope, State, Transaction};
use smallvec::{smallvec, SmallVec};
/// Undo-tree style history store.
pub struct History {
revisions: Vec<Revision>,
cursor: usize,
//
}
#[derive(Debug)]
struct Revision {
// prev: usize,
parent: usize,
children: SmallVec<[(usize, Transaction); 1]>,
/// The transaction to revert to previous state.
revert: Transaction,
// selection before, selection after?
@ -22,6 +22,7 @@ impl Default for History {
Self {
revisions: vec![Revision {
parent: 0,
children: SmallVec::new(),
revert: Transaction::from(ChangeSet::new(&Rope::new())),
}],
cursor: 0,
@ -31,18 +32,24 @@ impl Default for History {
impl History {
pub fn commit_revision(&mut self, transaction: &Transaction, original: &State) {
// TODO: store both directions
// TODO: could store a single set if deletes also stored the text they delete
// TODO: could store a single transaction, if deletes also stored the text they delete
let revert = transaction.invert(original);
let new_cursor = self.revisions.len();
self.revisions.push(Revision {
parent: self.cursor,
children: SmallVec::new(),
revert,
});
self.cursor = new_cursor;
// TODO: child tracking too?
// add a reference to the parent
self.revisions
.get_mut(self.cursor)
.unwrap() // TODO: get_unchecked_mut
.children
.push((new_cursor, transaction.clone()));
self.cursor = new_cursor;
}
#[inline]
@ -57,9 +64,8 @@ impl History {
}
let current_revision = &self.revisions[self.cursor];
// unimplemented!("{:?}", revision);
// unimplemented!("{:?}", state.doc().len_chars());
// TODO: pass the return value through?
// TODO: pass the return value through? It should always succeed
let success = current_revision.revert.apply(state);
if !success {
@ -72,13 +78,16 @@ impl History {
pub fn redo(&mut self, state: &mut State) {
let current_revision = &self.revisions[self.cursor];
// TODO: pick the latest child
// for now, simply pick the latest child (linear undo / redo)
if let Some((index, transaction)) = current_revision.children.last() {
let success = transaction.apply(state);
// if !success {
// panic!("Failed to apply undo!");
// }
if !success {
panic!("Failed to apply redo!");
}
unimplemented!()
self.cursor = *index;
}
}
}