Clean up

backend/reconcile/src/operation_transformation/merge_context.rs

@@ -2,7 +2,7 @@ use core::fmt::Debug;
 
 use crate::operation_transformation::Operation;
 
-#[derive(Clone)]
+#[derive(Clone, Debug)]
 pub struct MergeContext<T>
 where
     T: PartialEq + Clone + std::fmt::Debug,
@@ -23,26 +23,19 @@ where
     }
 }
 
-impl<T> Debug for MergeContext<T>
-where
-    T: PartialEq + Clone + std::fmt::Debug,
-{
-    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
-        f.debug_struct("MergeContext")
-            .field("last_operation", &self.last_operation)
-            .field("shift", &self.shift)
-            .finish()
-    }
-}
-
 impl<T> MergeContext<T>
 where
     T: PartialEq + Clone + std::fmt::Debug,
 {
     pub fn last_operation(&self) -> Option<&Operation<T>> { self.last_operation.as_ref() }
 
+    pub fn replace_last_operation(&mut self, operation: Option<Operation<T>>) {
+        self.last_operation = operation;
+    }
+
     /// Replace the last delete operation (if there was one) with a new one
-    /// while applying it to the shift.
+    /// while applying it to the `shift` in case the last operation
+    /// was a delete.
     pub fn consume_and_replace_last_operation(&mut self, operation: Option<Operation<T>>) {
         if let Some(Operation::Delete {
             deleted_character_count,
@@ -55,32 +48,22 @@ where
         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
+    /// threshold operation. This updates the `shift` in case the last operation
     /// was a delete.
-    pub fn consume_last_operation_if_it_is_too_behind(
+    pub fn consume_last_operation_if_it_is_too_behind(&mut self, threshold_index: i64) {
-        &mut self,
-        threshold_operation: &Operation<T>,
-    ) {
         if let Some(last_operation) = self.last_operation.as_ref() {
             if let Operation::Delete {
                 deleted_character_count,
                 ..
             } = last_operation
             {
-                if threshold_operation.start_index() as i64 + self.shift
+                if threshold_index + self.shift > last_operation.end_index() as i64 {
-                    > last_operation.end_index() as i64
-                {
                     self.shift -= *deleted_character_count as i64;
                     self.last_operation = None;
                 }
             } else if let Operation::Insert { .. } = last_operation {
-                if threshold_operation.start_index() as i64 + self.shift
+                if threshold_index + self.shift - last_operation.len() as i64
-                    - last_operation.len() as i64
                     > last_operation.end_index() as i64
                 {
                     self.last_operation = None;