[Turbopack] new backend cleanup (vercel#71132)

### What?

review comments from vercel#70945

turbopack/crates/turbo-tasks-backend/src/backend/mod.rs

@@ -358,7 +358,7 @@ impl TurboTasksBackendInner {
 
             // Check the dirty count of the root node
             let dirty_tasks = get!(task, AggregatedDirtyContainerCount)
-                .copied()
+                .cloned()
                 .unwrap_or_default()
                 .get(self.session_id);
             if dirty_tasks > 0 || is_dirty {
@@ -375,7 +375,14 @@ impl TurboTasksBackendInner {
                         value: RootState::new(ActiveType::CachedActiveUntilClean, task_id),
                     });
                     // A newly added AggregateRoot need to make sure to schedule the tasks
-                    task_ids_to_schedule = get_many!(task, AggregatedDirtyContainer { task } count if count.get(self.session_id) > 0 => task);
+                    task_ids_to_schedule = get_many!(
+                        task,
+                        AggregatedDirtyContainer {
+                            task
+                        } count if count.get(self.session_id) > 0 => {
+                            *task
+                        }
+                    );
                     if is_dirty {
                         task_ids_to_schedule.push(task_id);
                     }
@@ -1076,7 +1083,7 @@ impl TurboTasksBackendInner {
         // handle cell counters: update max index and remove cells that are no longer used
         let mut removed_cells = HashMap::new();
         let mut old_counters: HashMap<_, _> =
-            get_many!(task, CellTypeMaxIndex { cell_type } max_index => (cell_type, max_index));
+            get_many!(task, CellTypeMaxIndex { cell_type } max_index => (*cell_type, *max_index));
         for (&cell_type, &max_index) in cell_counters.iter() {
             if let Some(old_max_index) = old_counters.remove(&cell_type) {
                 if old_max_index != max_index {
@@ -1234,7 +1241,7 @@ impl TurboTasksBackendInner {
 
         let data_update = if old_dirty_state.is_some() || new_dirty_state.is_some() {
             let mut dirty_containers = get!(task, AggregatedDirtyContainerCount)
-                .copied()
+                .cloned()
                 .unwrap_or_default();
             if let Some(old_dirty_state) = old_dirty_state {
                 dirty_containers.update_with_dirty_state(&old_dirty_state);
@@ -1245,7 +1252,7 @@ impl TurboTasksBackendInner {
                 (None, Some(new)) => dirty_containers.update_with_dirty_state(&new),
                 (Some(old), Some(new)) => dirty_containers.replace_dirty_state(&old, &new),
             };
-            if !aggregated_update.is_default() {
+            if !aggregated_update.is_zero() {
                 if aggregated_update.get(self.session_id) < 0 {
                     if let Some(root_state) = get!(task, AggregateRoot) {
                         root_state.all_clean_event.notify(usize::MAX);
@@ -1403,7 +1410,7 @@ impl TurboTasksBackendInner {
                 task,
                 AggregatedCollectible {
                     collectible
-                } count if collectible.collectible_type == collectible_type && count > 0 => {
+                } count if collectible.collectible_type == collectible_type && *count > 0 => {
                     collectible.cell
                 }
             ) {
@@ -1416,7 +1423,7 @@ impl TurboTasksBackendInner {
                 Collectible {
                     collectible
                 } count if collectible.collectible_type == collectible_type => {
-                    (collectible.cell, count)
+                    (collectible.cell, *count)
                 }
             ) {
                 *collectibles

turbopack/crates/turbo-tasks-backend/src/backend/operation/aggregation_update.rs

@@ -31,9 +31,9 @@ fn get_followers_with_aggregation_number(
     aggregation_number: u32,
 ) -> Vec<TaskId> {
     if is_aggregating_node(aggregation_number) {
-        get_many!(task, Follower { task } count if count > 0 => task)
+        get_many!(task, Follower { task } count if *count > 0 => *task)
     } else {
-        get_many!(task, Child { task } => task)
+        get_many!(task, Child { task } => *task)
     }
 }
 
@@ -42,11 +42,11 @@ fn get_followers(task: &TaskGuard<'_>) -> Vec<TaskId> {
 }
 
 pub fn get_uppers(task: &TaskGuard<'_>) -> Vec<TaskId> {
-    get_many!(task, Upper { task } count if count > 0 => task)
+    get_many!(task, Upper { task } count if *count > 0 => *task)
 }
 
 fn iter_uppers<'a>(task: &'a TaskGuard<'a>) -> impl Iterator<Item = TaskId> + 'a {
-    iter_many!(task, Upper { task } count if count > 0 => task)
+    iter_many!(task, Upper { task } count if *count > 0 => *task)
 }
 
 pub fn get_aggregation_number(task: &TaskGuard<'_>) -> u32 {
@@ -126,17 +126,17 @@ impl AggregatedDataUpdate {
         let aggregation = get_aggregation_number(task);
         let mut dirty_container_count = Default::default();
         let mut collectibles_update: Vec<_> =
-            get_many!(task, Collectible { collectible } => (collectible, 1));
+            get_many!(task, Collectible { collectible } => (*collectible, 1));
         if is_aggregating_node(aggregation) {
             dirty_container_count = get!(task, AggregatedDirtyContainerCount)
-                .copied()
+                .cloned()
                 .unwrap_or_default();
             let collectibles = iter_many!(
                 task,
                 AggregatedCollectible {
                     collectible
-                } count if count > 0 => {
-                    collectible
+                } count if *count > 0 => {
+                    *collectible
                 }
             );
             for collectible in collectibles {
@@ -148,7 +148,7 @@ impl AggregatedDataUpdate {
         }
 
         let mut result = Self::new().collectibles_update(collectibles_update);
-        if !dirty_container_count.is_default() {
+        if !dirty_container_count.is_zero() {
             let DirtyContainerCount {
                 count,
                 count_in_session,
@@ -170,7 +170,7 @@ impl AggregatedDataUpdate {
             collectibles_update,
         } = &mut self;
         if let Some((_, value)) = dirty_container_update.as_mut() {
-            *value = value.invert()
+            *value = value.negate()
         }
         for (_, value) in collectibles_update.iter_mut() {
             *value = -*value;
@@ -199,7 +199,7 @@ impl AggregatedDataUpdate {
                 })
             }
 
-            let mut aggregated_update = Default::default();
+            let mut aggregated_update = DirtyContainerCount::default();
             update!(
                 task,
                 AggregatedDirtyContainer {
@@ -208,7 +208,7 @@ impl AggregatedDataUpdate {
                 |old: Option<DirtyContainerCount>| {
                     let mut new = old.unwrap_or_default();
                     aggregated_update = new.update_count(count);
-                    (!new.is_default()).then_some(new)
+                    (!new.is_zero()).then_some(new)
                 }
             );
 
@@ -225,10 +225,10 @@ impl AggregatedDataUpdate {
                 if let Some(dirty_state) = dirty_state {
                     new.undo_update_with_dirty_state(&dirty_state);
                 }
-                if !aggregated_update.is_default() {
+                if !aggregated_update.is_zero() {
                     result.dirty_container_update = Some((task_id, aggregated_update));
                 }
-                (!new.is_default()).then_some(new)
+                (!new.is_zero()).then_some(new)
             });
             if let Some((_, count)) = result.dirty_container_update.as_ref() {
                 if count.get(session_id) < 0 {
@@ -269,8 +269,8 @@ impl AggregatedDataUpdate {
                     CollectiblesDependent {
                         collectible_type,
                         task,
-                    } if collectible_type == ty => {
-                        task
+                    } if *collectible_type == ty => {
+                        *task
                     }
                 );
                 if !dependent.is_empty() {
@@ -608,7 +608,7 @@ impl AggregationUpdateQueue {
                         value: RootState::new(ActiveType::CachedActiveUntilClean, task_id),
                     });
                 }
-                let dirty_containers: Vec<_> = get_many!(task, AggregatedDirtyContainer { task } count if count.get(session_id) > 0 => task);
+                let dirty_containers: Vec<_> = get_many!(task, AggregatedDirtyContainer { task } count if count.get(session_id) > 0 => *task);
                 if !dirty_containers.is_empty() {
                     self.push(AggregationUpdateJob::FindAndScheduleDirty {
                         task_ids: dirty_containers,
@@ -954,7 +954,7 @@ impl AggregationUpdateQueue {
             if !is_aggregating_node(old) && is_aggregating_node(aggregation_number) {
                 // When converted from leaf to aggregating node, all children become
                 // followers
-                let children: Vec<_> = get_many!(task, Child { task } => task);
+                let children: Vec<_> = get_many!(task, Child { task } => *task);
                 for child_id in children {
                     task.add_new(CachedDataItem::Follower {
                         task: child_id,
@@ -966,7 +966,7 @@ impl AggregationUpdateQueue {
             if is_aggregating_node(aggregation_number) {
                 // followers might become inner nodes when the aggregation number is
                 // increased
-                let followers = iter_many!(task, Follower { task } count if count > 0 => task);
+                let followers = iter_many!(task, Follower { task } count if *count > 0 => *task);
                 for follower_id in followers {
                     self.push(AggregationUpdateJob::BalanceEdge {
                         upper_id: task_id,
@@ -978,7 +978,7 @@ impl AggregationUpdateQueue {
                     self.push(AggregationUpdateJob::BalanceEdge { upper_id, task_id });
                 }
             } else {
-                let children = iter_many!(task, Child { task } => task);
+                let children = iter_many!(task, Child { task } => *task);
                 for child_id in children {
                     self.push(AggregationUpdateJob::UpdateAggregationNumber {
                         task_id: child_id,

turbopack/crates/turbo-tasks-backend/src/backend/operation/invalidate.rs

@@ -112,23 +112,23 @@ pub fn make_task_dirty_internal(
         }) => {
             // Got dirty in that one session only
             let mut dirty_container = get!(task, AggregatedDirtyContainerCount)
-                .copied()
+                .cloned()
                 .unwrap_or_default();
             dirty_container.update_session_dependent(session_id, 1);
             dirty_container
         }
         None => {
             // Get dirty for all sessions
             get!(task, AggregatedDirtyContainerCount)
-                .copied()
+                .cloned()
                 .unwrap_or_default()
         }
         _ => unreachable!(),
     };
     let aggregated_update = dirty_container.update_with_dirty_state(&DirtyState {
         clean_in_session: None,
     });
-    if !aggregated_update.is_default() {
+    if !aggregated_update.is_zero() {
         queue.extend(AggregationUpdateJob::data_update(
             task,
             AggregatedDataUpdate::new().dirty_container_update(task_id, aggregated_update),

turbopack/crates/turbo-tasks-backend/src/backend/operation/update_cell.rs

@@ -40,9 +40,9 @@ impl UpdateCellOperation {
 
         let dependent = get_many!(
             task,
-            CellDependent { cell: dependent_cell, task } _value
-            if dependent_cell == cell
-            => task
+            CellDependent { cell: dependent_cell, task }
+            if *dependent_cell == cell
+            => *task
         );
 
         drop(task);

turbopack/crates/turbo-tasks-backend/src/backend/operation/update_output.rs

@@ -103,8 +103,8 @@ impl UpdateOutputOperation {
             value: output_value,
         });
 
-        let dependent_tasks = get_many!(task, OutputDependent { task } => task);
-        let children = get_many!(task, Child { task } => task);
+        let dependent_tasks = get_many!(task, OutputDependent { task } => *task);
+        let children = get_many!(task, Child { task } => *task);
 
         let mut queue = AggregationUpdateQueue::new();
 

turbopack/crates/turbo-tasks-backend/src/backend/storage.rs

@@ -435,7 +435,7 @@ macro_rules! iter_many {
         $task
             .iter($crate::data::indicies::$key)
             .filter_map(|(key, _)| match key {
-                &$crate::data::CachedDataItemKey::$key $key_pattern $(if $cond)? => Some(
+                $crate::data::CachedDataItemKey::$key $key_pattern $(if $cond)? => Some(
                     $iter_item
                 ),
                 _ => None,
@@ -446,8 +446,8 @@ macro_rules! iter_many {
             .iter($crate::data::indicies::$key)
             .filter_map(|(key, value)| match (key, value) {
                 (
-                    &$crate::data::CachedDataItemKey::$key $input,
-                    &$crate::data::CachedDataItemValue::$key { value: $value_pattern }
+                    $crate::data::CachedDataItemKey::$key $input,
+                    $crate::data::CachedDataItemValue::$key { value: $value_pattern }
                 ) $(if $cond)? => Some($iter_item),
                 _ => None,
             })

turbopack/crates/turbo-tasks-backend/src/data.rs

@@ -108,13 +108,18 @@ fn add_with_diff(v: &mut i32, u: i32) -> i32 {
     }
 }
 
-#[derive(Debug, Default, Clone, Copy, Serialize, Deserialize, PartialEq, Eq)]
+/// Represents a count of dirty containers. Since dirtyness can be session dependent, there might be
+/// a different count for a specific session. It only need to store the highest session count, since
+/// old sessions can't be visited again, so we can ignore their counts.
+#[derive(Debug, Default, Clone, Serialize, Deserialize, PartialEq, Eq)]
 pub struct DirtyContainerCount {
     pub count: i32,
     pub count_in_session: Option<(SessionId, i32)>,
 }
 
 impl DirtyContainerCount {
+    /// Get the count for a specific session. It's only expected to be asked for the current
+    /// session, since old session counts might be dropped.
     pub fn get(&self, session: SessionId) -> i32 {
         if let Some((s, count)) = self.count_in_session {
             if s == session {
@@ -124,13 +129,16 @@ impl DirtyContainerCount {
         self.count
     }
 
+    /// Increase/decrease the count by the given value.
     pub fn update(&mut self, count: i32) -> DirtyContainerCount {
         self.update_count(&DirtyContainerCount {
             count,
             count_in_session: None,
         })
     }
 
+    /// Increase/decrease the count by the given value, but does not update the count for a specific
+    /// session. This matches the "dirty, but clean in one session" behavior.
     pub fn update_session_dependent(
         &mut self,
         ignore_session: SessionId,
@@ -142,6 +150,10 @@ impl DirtyContainerCount {
         })
     }
 
+    /// Adds the `count` to the current count. This correctly handles session dependent counts.
+    /// Returns a new count object that represents the aggregated count. The aggregated count will
+    /// be +1 when the self count changes from <= 0 to > 0 and -1 when the self count changes from >
+    /// 0 to <= 0. The same for the session dependent count.
     pub fn update_count(&mut self, count: &DirtyContainerCount) -> DirtyContainerCount {
         let mut diff = DirtyContainerCount::default();
         match (
@@ -181,6 +193,7 @@ impl DirtyContainerCount {
         diff
     }
 
+    /// Applies a dirty state to the count. Returns an aggregated count that represents the change.
     pub fn update_with_dirty_state(&mut self, dirty: &DirtyState) -> DirtyContainerCount {
         if let Some(clean_in_session) = dirty.clean_in_session {
             self.update_session_dependent(clean_in_session, 1)
@@ -189,6 +202,8 @@ impl DirtyContainerCount {
         }
     }
 
+    /// Undoes the effect of a dirty state on the count. Returns an aggregated count that represents
+    /// the change.
     pub fn undo_update_with_dirty_state(&mut self, dirty: &DirtyState) -> DirtyContainerCount {
         if let Some(clean_in_session) = dirty.clean_in_session {
             self.update_session_dependent(clean_in_session, -1)
@@ -197,6 +212,8 @@ impl DirtyContainerCount {
         }
     }
 
+    /// Replaces the old dirty state with the new one. Returns an aggregated count that represents
+    /// the change.
     pub fn replace_dirty_state(
         &mut self,
         old: &DirtyState,
@@ -207,11 +224,13 @@ impl DirtyContainerCount {
         diff
     }
 
-    pub fn is_default(&self) -> bool {
+    /// Returns true if the count is zero and appling it would have no effect
+    pub fn is_zero(&self) -> bool {
         self.count == 0 && self.count_in_session.map(|(_, c)| c == 0).unwrap_or(true)
     }
 
-    pub fn invert(&self) -> Self {
+    /// Negates the counts.
+    pub fn negate(&self) -> Self {
         Self {
             count: -self.count,
             count_in_session: self.count_in_session.map(|(s, c)| (s, -c)),