From 4543063f5a160f0aecac8a7232483fa7404d8da7 Mon Sep 17 00:00:00 2001
From: Phoebe Szmucer <phoebe.szmucer@gmail.com>
Date: Mon, 22 Jul 2024 10:19:36 +0100
Subject: [PATCH] use a queue

---
 src/function/accumulated.rs |  7 ++++---
 tests/accumulate-dag.rs     | 12 +++++------
 tests/accumulate.rs         | 42 ++++++++++++++++++-------------------
 3 files changed, 31 insertions(+), 30 deletions(-)

diff --git a/src/function/accumulated.rs b/src/function/accumulated.rs
index 51b16fa..5cd3ef9 100644
--- a/src/function/accumulated.rs
+++ b/src/function/accumulated.rs
@@ -1,4 +1,5 @@
 use crate::{accumulator, hash::FxHashSet, storage::DatabaseGen, DatabaseKeyIndex, Id};
+use std::collections::VecDeque;
 
 use super::{Configuration, IngredientImpl};
 
@@ -23,9 +24,9 @@ where
 
         let db_key = self.database_key_index(key);
         let mut visited: FxHashSet<DatabaseKeyIndex> = std::iter::once(db_key).collect();
-        let mut stack = vec![db_key];
+        let mut queue: VecDeque<DatabaseKeyIndex> = std::iter::once(db_key).collect();
 
-        while let Some(k) = stack.pop() {
+        while let Some(k) = queue.pop_front() {
             accumulator.produced_by(runtime, k, &mut output);
 
             let origin = db.lookup_ingredient(k.ingredient_index).origin(k.key_index);
@@ -34,7 +35,7 @@ where
             for input in inputs {
                 if let Ok(input) = input.try_into() {
                     if visited.insert(input) {
-                        stack.push(input);
+                        queue.push_back(input);
                     }
                 }
             }
diff --git a/tests/accumulate-dag.rs b/tests/accumulate-dag.rs
index d7decab..d0c0cfe 100644
--- a/tests/accumulate-dag.rs
+++ b/tests/accumulate-dag.rs
@@ -45,6 +45,12 @@ fn accumulate_a_called_twice() {
         // Check that we don't see logs from `a` appearing twice in the input.
         expect![[r#"
             [
+                Log(
+                    "log_a(0 of 2)",
+                ),
+                Log(
+                    "log_a(1 of 2)",
+                ),
                 Log(
                     "log_b(0 of 3)",
                 ),
@@ -54,12 +60,6 @@ fn accumulate_a_called_twice() {
                 Log(
                     "log_b(2 of 3)",
                 ),
-                Log(
-                    "log_a(0 of 2)",
-                ),
-                Log(
-                    "log_a(1 of 2)",
-                ),
             ]"#]]
         .assert_eq(&format!("{:#?}", logs));
     })
diff --git a/tests/accumulate.rs b/tests/accumulate.rs
index 0387bac..3b6ce19 100644
--- a/tests/accumulate.rs
+++ b/tests/accumulate.rs
@@ -94,6 +94,12 @@ fn accumulate_once() {
     // (execution order).
     expect![[r#"
         [
+            Log(
+                "log_a(0 of 2)",
+            ),
+            Log(
+                "log_a(1 of 2)",
+            ),
             Log(
                 "log_b(0 of 3)",
             ),
@@ -103,12 +109,6 @@ fn accumulate_once() {
             Log(
                 "log_b(2 of 3)",
             ),
-            Log(
-                "log_a(0 of 2)",
-            ),
-            Log(
-                "log_a(1 of 2)",
-            ),
         ]"#]]
     .assert_eq(&format!("{:#?}", logs));
 }
@@ -122,6 +122,12 @@ fn change_a_from_2_to_0() {
     let logs = push_logs::accumulated::<Log>(&db, input);
     expect![[r#"
         [
+            Log(
+                "log_a(0 of 2)",
+            ),
+            Log(
+                "log_a(1 of 2)",
+            ),
             Log(
                 "log_b(0 of 3)",
             ),
@@ -131,12 +137,6 @@ fn change_a_from_2_to_0() {
             Log(
                 "log_b(2 of 3)",
             ),
-            Log(
-                "log_a(0 of 2)",
-            ),
-            Log(
-                "log_a(1 of 2)",
-            ),
         ]"#]]
     .assert_eq(&format!("{:#?}", logs));
     db.assert_logs(expect![[r#"
@@ -177,6 +177,12 @@ fn change_a_from_2_to_1() {
     let logs = push_logs::accumulated::<Log>(&db, input);
     expect![[r#"
         [
+            Log(
+                "log_a(0 of 2)",
+            ),
+            Log(
+                "log_a(1 of 2)",
+            ),
             Log(
                 "log_b(0 of 3)",
             ),
@@ -186,12 +192,6 @@ fn change_a_from_2_to_1() {
             Log(
                 "log_b(2 of 3)",
             ),
-            Log(
-                "log_a(0 of 2)",
-            ),
-            Log(
-                "log_a(1 of 2)",
-            ),
         ]"#]]
     .assert_eq(&format!("{:#?}", logs));
     db.assert_logs(expect![[r#"
@@ -206,6 +206,9 @@ fn change_a_from_2_to_1() {
     let logs = push_logs::accumulated::<Log>(&db, input);
     expect![[r#"
         [
+            Log(
+                "log_a(0 of 1)",
+            ),
             Log(
                 "log_b(0 of 3)",
             ),
@@ -215,9 +218,6 @@ fn change_a_from_2_to_1() {
             Log(
                 "log_b(2 of 3)",
             ),
-            Log(
-                "log_a(0 of 1)",
-            ),
         ]"#]]
     .assert_eq(&format!("{:#?}", logs));
     db.assert_logs(expect![[r#"