cache remove-before-insert ops

src/json.rs

@@ -37,6 +37,7 @@ pub struct Json {
     summary:    Summary,
     site_id:    SiteId,
     cached_ops: Vec<Op>,
+    outoforder_ops: Vec<Op>,
 }
 
 #[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
@@ -103,7 +104,7 @@ impl Json {
         let mut summary = Summary::default();
         let dot = summary.get_dot(site_id);
         let inner = local_value.into_json(dot)?;
-        Ok(Json{inner, summary, site_id, cached_ops: vec![]})
+        Ok(Json{inner, summary, site_id, outoforder_ops: vec![], cached_ops: vec![]})
     }
 
     /// Constructs and returns a new `Json` CRDT with site 1 from an
@@ -179,7 +180,7 @@ impl Json {
         JsonState,
         Inner,
         Op,
-        Option<LocalOp>,
+        LocalOp,
         SJValue,
     }
 }
@@ -479,6 +480,14 @@ impl Op {
             OpInner::String(ref op) => op.inserted_dots(),
         }
     }
+
+    fn removed_dots(&self) -> Vec<Dot> {
+        match self.op {
+            OpInner::Object(ref op) => op.removed_dots(),
+            OpInner::Array(ref op) => op.removed_dots(),
+            OpInner::String(ref op) => op.removed_dots(),
+        }
+    }
 }
 
 impl NestedOp for Op {

src/list.rs

@@ -36,6 +36,7 @@ pub struct List<T: 'static> {
     summary:    Summary,
     site_id:    SiteId,
     cached_ops: Vec<Op<T>>,
+    outoforder_ops: Vec<Op<T>>,
 }
 
 #[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
@@ -92,7 +93,7 @@ impl<T: Clone> List<T> {
         let inner   = Inner::new();
         let summary = Summary::default();
         let site_id = 1;
-        List{inner, summary, site_id, cached_ops: vec![]}
+        List{inner, summary, site_id, outoforder_ops: vec![], cached_ops: vec![]}
     }
 
     /// Returns the number of elements in the list.
@@ -158,7 +159,7 @@ impl<T: Clone> List<T> {
         ListState,
         Inner<T>,
         Op<T>,
-        Option<LocalOp<T>>,
+        LocalOp<T>,
         Vec<T>,
     }
 }
@@ -423,6 +424,13 @@ impl<T> Op<T> {
             vec![]
         }
     }
+
+    pub(crate) fn removed_dots(&self) -> Vec<Dot> {
+        match *self {
+            Op::Insert(_) => vec![],
+            Op::Remove(ref uid) => vec![uid.dot()],
+        }
+    }
 }
 
 impl<T: NestedInner> NestedOp for Op<T> {

src/map.rs

@@ -48,6 +48,7 @@ pub struct Map<K: Key, V: Value> {
     summary:    Summary,
     site_id:    SiteId,
     cached_ops: Vec<Op<K, V>>,
+    outoforder_ops: Vec<Op<K, V>>,
 }
 
 #[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
@@ -109,7 +110,7 @@ impl<K: Key, V: Value> Map<K, V> {
         let inner   = Inner::new();
         let summary = Summary::default();
         let site_id = 1;
-        Map{inner, summary, site_id, cached_ops: vec![]}
+        Map{inner, summary, site_id, outoforder_ops: vec![], cached_ops: vec![]}
     }
 
     /// Returns true iff the map has the key.
@@ -378,7 +379,7 @@ impl<K: Key, V: Value> Op<K, V> {
     pub fn inserted_element(&self) -> Option<&Element<V>> { self.inserted_element.as_ref() }
 
     /// Returns a reference to the `Op`'s removed dots.
-    pub fn removed_dots(&self) -> &[Dot] { &self.removed_dots }
+    pub fn removed_dots(&self) -> Vec<Dot> { self.removed_dots.clone() }
 
     /// Assigns a site id to any unassigned inserts and removes
     pub fn add_site_id(&mut self, site_id: SiteId) {

src/set.rs

@@ -45,6 +45,7 @@ pub struct Set<T: SetElement> {
     summary:    Summary,
     site_id:    SiteId,
     cached_ops: Vec<Op<T>>,
+    outoforder_ops: Vec<Op<T>>,
 }
 
 #[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
@@ -78,7 +79,7 @@ impl<T: SetElement> Set<T> {
         let inner   = Inner::new();
         let summary = Summary::default();
         let site_id = 1;
-        Set{inner, summary, site_id, cached_ops: vec![]}
+        Set{inner, summary, site_id, outoforder_ops: vec![], cached_ops: vec![]}
     }
 
     /// Returns true iff the set contains the value.
@@ -112,7 +113,7 @@ impl<T: SetElement> Set<T> {
         SetState,
         Inner<T>,
         Op<T>,
-        Option<LocalOp<T>>,
+        LocalOp<T>,
         HashSet<T>,
     }
 }

src/text/mod.rs

@@ -42,6 +42,7 @@ pub struct Text {
     site_id:    SiteId,
     summary:    Summary,
     cached_ops: Vec<Op>,
+    outoforder_ops: Vec<Op>,
 }
 
 #[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
@@ -77,7 +78,7 @@ impl Text {
         let inner   = Inner::new();
         let summary = Summary::default();
         let site_id = 1;
-        Text{inner, summary, site_id, cached_ops: vec![]}
+        Text{inner, summary, site_id, outoforder_ops: vec![], cached_ops: vec![]}
     }
 
     /// Constructs and returns a new Text CRDT from a string.
@@ -117,7 +118,7 @@ impl Text {
         TextState,
         Inner,
         Op,
-        Vec<LocalOp>,
+        LocalOp,
         String,
     }
 }
@@ -358,6 +359,10 @@ impl Op {
         self.inserted_elements.iter().map(|elt| elt.uid.dot()).collect()
     }
 
+    pub fn removed_dots(&self) -> Vec<Dot> {
+        self.removed_uids.iter().map(|uid| uid.dot()).collect()
+    }
+
     #[doc(hidden)]
     pub fn inserted_elements(&self) -> &[Element] {
         &self.inserted_elements

src/traits.rs

@@ -11,7 +11,6 @@ macro_rules! crdt_impl2 {
      $local_op:ty,
      $local_value:ty,
     ) => {
-
         /// Returns the site id.
         pub fn site_id(&self) -> SiteId {
             self.site_id
@@ -64,6 +63,7 @@ macro_rules! crdt_impl2 {
                 site_id,
                 inner: state.inner.into_owned(),
                 summary: state.summary.into_owned(),
+                outoforder_ops: vec![],
                 cached_ops: vec![],
             })
         }
@@ -76,16 +76,30 @@ macro_rules! crdt_impl2 {
         /// Executes an op and returns the equivalent local op.
         /// This function assumes that the op always inserts values
         /// from the correct site. For untrusted ops, used `validate_and_execute_op`.
-        pub fn execute_op(&mut self, op: $op) -> $local_op {
+        pub fn execute_op(&mut self, op: $op) -> Vec<$local_op> {
+            use traits::IntoVec;
+
             for dot in op.inserted_dots() {
                 self.summary.insert(dot);
             }
-            self.inner.execute_op(op)
+
+            if Self::is_outoforder(&op, &self.summary) {
+                self.outoforder_ops.push(op);
+                return vec![]
+            }
+
+            let mut local_ops: Vec<$local_op> = self.inner.execute_op(op).into_vec();
+
+            while let Some(op) = self.pop_outoforder_op() {
+                local_ops.append(&mut self.inner.execute_op(op).into_vec());
+            }
+
+            local_ops
         }
 
         /// Validates that an op only inserts elements from a given site id,
         /// then executes the op and returns the equivalent local op.
-        pub fn validate_and_execute_op(&mut self, op: $op, site_id: SiteId) -> Result<$local_op, Error> {
+        pub fn validate_and_execute_op(&mut self, op: $op, site_id: SiteId) -> Result<Vec<$local_op>, Error> {
             op.validate(site_id)?;
             Ok(self.execute_op(op))
         }
@@ -116,6 +130,15 @@ macro_rules! crdt_impl2 {
                 .collect())
         }
 
+        fn is_outoforder(op: &$op, summary: &Summary) -> bool {
+            op.removed_dots().iter().any(|dot| !summary.contains(dot))
+        }
+
+        fn pop_outoforder_op(&mut self) -> Option<$op> {
+            let idx = self.outoforder_ops.iter().position(|op| Self::is_outoforder(&op, &self.summary))?;
+            Some(self.outoforder_ops.remove(idx))
+        }
+
         fn after_op(&mut self, op: $op) -> Result<$op, Error> {
             if self.site_id == 0 {
                 self.cached_ops.push(op);
@@ -127,6 +150,26 @@ macro_rules! crdt_impl2 {
     }
 }
 
+pub(crate) trait IntoVec<T> {
+    fn into_vec(self) -> Vec<T>;
+}
+
+impl<T> IntoVec<T> for Option<T> {
+    fn into_vec(self) -> Vec<T> {
+        if let Some(value) = self { vec![value] } else { vec![] }
+    }
+}
+
+impl<T> IntoVec<T> for T {
+    fn into_vec(self) -> Vec<T> {
+        vec![self]
+    }
+}
+
+impl<T> IntoVec<T> for Vec<T> {
+    fn into_vec(self) -> Vec<T> { self }
+}
+
 pub(crate) trait NestedInner: Sized {
     fn nested_add_site_id(&mut self, site_id: SiteId);