From 86e56d20530658706eae8d1415707ed181c6bc52 Mon Sep 17 00:00:00 2001
From: Alexis Sellier <self@cloudhead.io>
Date: Wed, 28 Dec 2022 18:38:01 +0100
Subject: [PATCH] cob: Move graph sorting to `evaluate` function

This avoids passing the sorted items as an iterator.

Signed-off-by: Alexis Sellier <self@cloudhead.io>
---
 radicle-cob/src/change_graph.rs            | 15 +------------
 radicle-cob/src/change_graph/evaluation.rs | 25 +++++++++++-----------
 radicle-cob/src/history.rs                 | 12 +++++------
 3 files changed, 20 insertions(+), 32 deletions(-)

diff --git a/radicle-cob/src/change_graph.rs b/radicle-cob/src/change_graph.rs
index 2b883787..23833bb3 100644
--- a/radicle-cob/src/change_graph.rs
+++ b/radicle-cob/src/change_graph.rs
@@ -93,20 +93,7 @@ impl ChangeGraph {
         let (root, root_node) = roots.first().unwrap();
         let manifest = root_node.manifest.clone();
         let rng = fastrand::Rng::new();
-        let items = self.graph.sorted(rng).into_iter().map(|oid| {
-            let node = &self.graph[&oid];
-            let child_commits = node
-                .dependents
-                .iter()
-                .map(|e| *self.graph[e].id())
-                .collect::<Vec<_>>();
-
-            (&node.value, oid, child_commits)
-        });
-        let history = {
-            let root_change = &self.graph[*root];
-            evaluate(*root_change.id(), &self.graph, items)
-        };
+        let history = evaluate(*self.graph[*root].id(), &self.graph, rng);
 
         CollaborativeObject {
             manifest,
diff --git a/radicle-cob/src/change_graph/evaluation.rs b/radicle-cob/src/change_graph/evaluation.rs
index 9de460c2..4b9ed7c8 100644
--- a/radicle-cob/src/change_graph/evaluation.rs
+++ b/radicle-cob/src/change_graph/evaluation.rs
@@ -15,17 +15,18 @@ use crate::{change::Change, history, pruning_fold};
 /// # Panics
 ///
 /// If the change corresponding to the root OID is not in `items`
-pub fn evaluate<'b>(
-    root: Oid,
-    graph: &Dag<Oid, Change>,
-    items: impl Iterator<Item = (&'b Change, Oid, Vec<Oid>)>,
-) -> history::History {
+pub fn evaluate(root: Oid, graph: &Dag<Oid, Change>, rng: fastrand::Rng) -> history::History {
     let entries = pruning_fold::pruning_fold(
         HashMap::<EntryId, EntryWithClock>::new(),
-        items.map(|(change, idx, children)| ChangeWithChildren {
-            idx,
-            change,
-            child_commits: children,
+        graph.sorted(rng).into_iter().map(|oid| {
+            let node = &graph[&oid];
+            let child_commits = node.dependents.iter().copied().collect();
+
+            ChangeWithChildren {
+                oid,
+                change: &node.value,
+                child_commits,
+            }
         }),
         |mut entries, c| match evaluate_change(c.change, &c.child_commits) {
             Err(RejectionReason::InvalidSignatures) => {
@@ -37,11 +38,11 @@ pub fn evaluate<'b>(
             }
             Ok(entry) => {
                 // Get parent commits and calculate this node's clock based on theirs.
-                let clock = graph[&c.idx]
+                let clock = graph[&c.oid]
                     .dependencies
                     .iter()
                     .map(|e| {
-                        let entry = &entries[&graph[e].id.into()];
+                        let entry = &entries[&EntryId::from(*e)];
                         let clock = entry.clock();
 
                         clock + entry.contents().len() as Clock - 1
@@ -81,7 +82,7 @@ fn evaluate_change(
 }
 
 struct ChangeWithChildren<'a> {
-    idx: Oid,
+    oid: Oid,
     change: &'a Change,
     child_commits: Vec<Oid>,
 }
diff --git a/radicle-cob/src/history.rs b/radicle-cob/src/history.rs
index adf66ac0..35252fa1 100644
--- a/radicle-cob/src/history.rs
+++ b/radicle-cob/src/history.rs
@@ -105,12 +105,12 @@ impl History {
     where
         F: for<'r> FnMut(A, &'r EntryWithClock) -> ControlFlow<A, A>,
     {
-        let sorted = self.graph.sorted(fastrand::Rng::new());
-        #[allow(clippy::let_and_return)]
-        let items = sorted.iter().map(|idx| {
-            let entry = &self.graph[idx];
-            entry
-        });
+        let items = self
+            .graph
+            .sorted(fastrand::Rng::new())
+            .into_iter()
+            .map(|idx| &self.graph[&idx]);
+
         pruning_fold::pruning_fold(init, items, f)
     }