From 97e280ddd226ab1c935ba45a83d27f7fdf7160d4 Mon Sep 17 00:00:00 2001
From: Niko Matsakis <niko@alum.mit.edu>
Date: Wed, 10 Aug 2022 03:46:27 -0400
Subject: [PATCH] track outputs for the active record

---
 .../salsa-2022/src/runtime/active_query.rs    | 25 +++++++++++++------
 .../salsa-2022/src/runtime/local_state.rs     |  4 +--
 2 files changed, 20 insertions(+), 9 deletions(-)

diff --git a/components/salsa-2022/src/runtime/active_query.rs b/components/salsa-2022/src/runtime/active_query.rs
index 02fa5c6f..4ef9c889 100644
--- a/components/salsa-2022/src/runtime/active_query.rs
+++ b/components/salsa-2022/src/runtime/active_query.rs
@@ -1,3 +1,5 @@
+use std::collections::BTreeSet;
+
 use crate::{
     durability::Durability,
     hash::{FxHashSet, FxIndexMap, FxIndexSet},
@@ -34,8 +36,15 @@ pub(super) struct ActiveQuery {
     /// Otherwise it is 1 more than the current value (which is incremented).
     pub(super) disambiguator_map: FxIndexMap<u64, Disambiguator>,
 
-    /// Tracks entities created by this query.
-    pub(super) entities_created: FxHashSet<DatabaseKeyIndex>,
+    /// Tracks values written by this query. Could be...
+    ///
+    /// * tracked structs created
+    /// * invocations of `specify`
+    /// * accumulators pushed to
+    ///
+    /// We use a btree-set because we want to be able to
+    /// extract the keys in sorted order.
+    pub(super) outputs: BTreeSet<DatabaseKeyIndex>,
 }
 
 impl ActiveQuery {
@@ -48,7 +57,7 @@ impl ActiveQuery {
             untracked_read: false,
             cycle: None,
             disambiguator_map: Default::default(),
-            entities_created: Default::default(),
+            outputs: Default::default(),
         }
     }
 
@@ -75,13 +84,15 @@ impl ActiveQuery {
         self.changed_at = self.changed_at.max(revision);
     }
 
-    pub(super) fn add_entity_created(&mut self, entity: DatabaseKeyIndex) {
-        let is_new = self.entities_created.insert(entity);
+    /// Adds a key to our list of outputs.
+    pub(super) fn add_output(&mut self, key: DatabaseKeyIndex) {
+        let is_new = self.outputs.insert(key);
         assert!(is_new);
     }
 
-    pub(super) fn was_entity_created(&self, entity: DatabaseKeyIndex) -> bool {
-        self.entities_created.contains(&entity)
+    /// True if the given key was output by this query.
+    pub(super) fn is_output(&self, key: DatabaseKeyIndex) -> bool {
+        self.outputs.contains(&key)
     }
 
     pub(crate) fn revisions(&self, runtime: &Runtime) -> QueryRevisions {
diff --git a/components/salsa-2022/src/runtime/local_state.rs b/components/salsa-2022/src/runtime/local_state.rs
index 785da66c..ab47a2b7 100644
--- a/components/salsa-2022/src/runtime/local_state.rs
+++ b/components/salsa-2022/src/runtime/local_state.rs
@@ -118,7 +118,7 @@ impl LocalState {
     pub(super) fn add_entity_created(&self, entity: DatabaseKeyIndex) {
         self.with_query_stack(|stack| {
             if let Some(top_query) = stack.last_mut() {
-                top_query.add_entity_created(entity)
+                top_query.add_output(entity)
             }
         })
     }
@@ -126,7 +126,7 @@ impl LocalState {
     pub(super) fn was_entity_created(&self, entity: DatabaseKeyIndex) -> bool {
         self.with_query_stack(|stack| {
             if let Some(top_query) = stack.last_mut() {
-                top_query.was_entity_created(entity)
+                top_query.is_output(entity)
             } else {
                 false
             }