andras/reconcile
1
0
Fork 0
Code Issues Pull requests 5 Projects Releases Packages Wiki Activity Actions

last_delete => last_operation

Browse source
This commit is contained in:
Andras Schmelczer 2024-11-28 21:30:17 +00:00
parent 44f9a44f63
commit 730038e0d0
No known key found for this signature in database
GPG key ID: FC8F2C3D3D1A718C
3 changed files with 66 additions and 33 deletions
Download patch file Download diff file Expand all files Collapse all files

2
backend/reconcile/src/operation_transformation/edited_text.rs
View file

@ -272,7 +272,7 @@ mod tests {
#[test]
fn test_calculate_operations_with_insert() {
let original = "hello world! ...";
let left = "Hello world! I'm Andras.";
let left = "hello world! I'm Andras.";
let right = "Hello world! How are you?";
let expected = "Hello world! I'm Andras.How are you?";

61
backend/reconcile/src/operation_transformation/merge_context.rs
View file

@ -5,7 +5,7 @@ pub struct MergeContext<T>
where
T: PartialEq + Clone,
{
pub last_delete: Option<Operation<T>>,
last_operation: Option<Operation<T>>,
pub shift: i64,
}
@ -15,7 +15,7 @@ where
{
fn default() -> Self {
MergeContext {
last_delete: None,
last_operation: None,
shift: 0,
}
}
@ -25,28 +25,49 @@ impl<T> MergeContext<T>
where
T: PartialEq + Clone,
{
/// Replace the last delete operation (if there was one) with a new one while
/// applying it to the shift.
pub fn replace_delete(&mut self, delete: Option<Operation<T>>) {
if let Some(produced_last_delete) = self.last_delete.take() {
self.shift -= produced_last_delete.len() as i64;
}
self.last_delete = delete;
pub fn last_operation(&self) -> Option<&Operation<T>> {
self.last_operation.as_ref()
}
/// Remove the last delete operation (if there was one) in case it is behind the
/// threshold operation.
pub fn consume_delete_if_behind_operation(&mut self, threshold_operation: &Operation<T>) {
match self.last_delete.as_ref() {
Some(last_delete)
if threshold_operation.start_index() as i64 + self.shift
> last_delete.end_index() as i64 =>
/// Replace the last delete operation (if there was one) with a new one while
/// applying it to the shift.
pub fn consume_and_replace_last_operation(&mut self, operation: Option<Operation<T>>) {
if let Some(Operation::Delete {
deleted_character_count,
..
}) = self.last_operation.take()
{
self.shift -= deleted_character_count as i64;
}
self.last_operation = operation;
}
pub fn replace_last_operation(&mut self, operation: Option<Operation<T>>) {
self.last_operation = operation;
}
/// Remove the last operation (if there was one) in case it is behind the
/// threshold operation. This changes the shift in case the last operation was
/// a delete.
pub fn consume_last_operation_if_it_is_too_behind(
&mut self,
threshold_operation: &Operation<T>,
) {
if let Some(last_operation) = self.last_operation.as_ref() {
if threshold_operation.start_index() as i64 + self.shift
> last_operation.end_index() as i64
{
self.shift -= last_delete.len() as i64;
self.last_delete = None;
if let Operation::Delete {
deleted_character_count,
..
} = last_operation
{
self.shift -= *deleted_character_count as i64;
}
self.last_operation = None;
}
_ => {}
}
}
}

36
backend/reconcile/src/operation_transformation/operation.rs
View file

@ -204,22 +204,31 @@ where
affecting_context: &mut MergeContext<T>,
produced_context: &mut MergeContext<T>,
) -> Option<Operation<T>> {
affecting_context.consume_delete_if_behind_operation(&self);
affecting_context.consume_last_operation_if_it_is_too_behind(&self);
let operation = self.with_shifted_index(affecting_context.shift);
match (operation, affecting_context.last_delete.clone()) {
match (operation, affecting_context.last_operation().clone()) {
(operation @ Operation::Insert { .. }, None) => {
produced_context.shift += operation.len() as i64;
Some(operation)
}
(operation @ Operation::Delete { .. }, None) => {
produced_context.replace_delete(Some(operation.clone()));
(operation, Some(last_insert @ Operation::Insert { .. })) => {
produced_context.shift += operation.len() as i64;
Some(operation)
}
(operation @ Operation::Insert { .. }, Some(last_delete)) => {
// We can never delete inside an insert
(operation @ Operation::Delete { .. }, None) => {
produced_context.consume_and_replace_last_operation(Some(operation.clone()));
Some(operation)
}
(
operation @ Operation::Insert { .. },
Some(last_delete @ Operation::Delete { .. }),
) => {
produced_context.shift += operation.len() as i64;
debug_assert!(
@ -231,16 +240,19 @@ where
let moved_operation = operation.with_index(last_delete.start_index());
affecting_context.last_delete = Operation::create_delete(
affecting_context.replace_last_operation(Operation::create_delete(
moved_operation.end_index() + 1,
(last_delete.len() as i64 - difference) as usize,
);
));
affecting_context.shift -= difference;
Some(moved_operation)
}
(operation @ Operation::Delete { .. }, Some(last_delete)) => {
(
operation @ Operation::Delete { .. },
Some(last_delete @ Operation::Delete { .. }),
) => {
debug_assert!(
last_delete.range().contains(&operation.start_index()),
"There is a last delete ({last_delete}) but the operation ({operation}) is not contained in it"
@ -253,13 +265,13 @@ where
0.max(operation.end_index() as i64 - last_delete.end_index() as i64) as usize,
);
affecting_context.shift -= difference;
affecting_context.last_delete = Operation::create_delete(
affecting_context.replace_last_operation(Operation::create_delete(
last_delete.start_index(),
0.max(last_delete.end_index() as i64 - operation.end_index() as i64) as usize,
);
));
affecting_context.shift -= difference;
produced_context.replace_delete(updated_delete.clone());
produced_context.consume_and_replace_last_operation(updated_delete.clone());
updated_delete
}