From 5b568cabcc3ac70bb3a3abf436fe78110d8f40ee Mon Sep 17 00:00:00 2001
From: Yuya Nishihara <yuya@tcha.org>
Date: Tue, 23 May 2023 17:59:45 +0900
Subject: [PATCH] revset: add iterator of (CommitId, ChangeId) pairs, use it in
 id_index

There are a few more places where we need these pairs.
---
 lib/src/default_revset_engine.rs |  8 ++++++++
 lib/src/id_prefix.rs             | 11 ++++-------
 lib/src/revset.rs                |  3 +++
 3 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/lib/src/default_revset_engine.rs b/lib/src/default_revset_engine.rs
index 9d78225c2..eaa6034c6 100644
--- a/lib/src/default_revset_engine.rs
+++ b/lib/src/default_revset_engine.rs
@@ -93,6 +93,14 @@ impl<'index> Revset<'index> for RevsetImpl<'index> {
         Box::new(self.inner.iter().map(|index_entry| index_entry.commit_id()))
     }
 
+    fn commit_change_ids(&self) -> Box<dyn Iterator<Item = (CommitId, ChangeId)> + '_> {
+        Box::new(
+            self.inner
+                .iter()
+                .map(|index_entry| (index_entry.commit_id(), index_entry.change_id())),
+        )
+    }
+
     fn iter_graph(&self) -> Box<dyn Iterator<Item = (CommitId, Vec<RevsetGraphEdge>)> + '_> {
         Box::new(RevsetGraphIterator::new(self.inner.iter()))
     }
diff --git a/lib/src/id_prefix.rs b/lib/src/id_prefix.rs
index e38088ea5..2c1357f0d 100644
--- a/lib/src/id_prefix.rs
+++ b/lib/src/id_prefix.rs
@@ -20,7 +20,7 @@ use crate::backend::{self, ChangeId, CommitId, ObjectId};
 use crate::index::{HexPrefix, PrefixResolution};
 use crate::op_store::WorkspaceId;
 use crate::repo::Repo;
-use crate::revset::{DefaultSymbolResolver, RevsetExpression, RevsetIteratorExt};
+use crate::revset::{DefaultSymbolResolver, RevsetExpression};
 
 struct PrefixDisambiguationError;
 
@@ -48,14 +48,11 @@ impl DisambiguationData {
                 .evaluate(repo)
                 .map_err(|_| PrefixDisambiguationError)?;
 
-            // TODO: We should be able to get the change IDs from the revset, without having
-            // to read the whole commit objects
             let mut commit_id_vec = vec![];
             let mut change_id_vec = vec![];
-            for commit in revset.iter().commits(repo.store()) {
-                let commit = commit.map_err(|_| PrefixDisambiguationError)?;
-                commit_id_vec.push((commit.id().clone(), ()));
-                change_id_vec.push((commit.change_id().clone(), commit.id().clone()));
+            for (commit_id, change_id) in revset.commit_change_ids() {
+                commit_id_vec.push((commit_id.clone(), ()));
+                change_id_vec.push((change_id, commit_id));
             }
             Ok(Indexes {
                 commit_index: IdIndex::from_vec(commit_id_vec),
diff --git a/lib/src/revset.rs b/lib/src/revset.rs
index e7b4f201c..08f155334 100644
--- a/lib/src/revset.rs
+++ b/lib/src/revset.rs
@@ -2029,6 +2029,9 @@ pub trait Revset<'index>: fmt::Debug {
     /// Iterate in topological order with children before parents.
     fn iter(&self) -> Box<dyn Iterator<Item = CommitId> + '_>;
 
+    /// Iterates commit/change id pairs in topological order.
+    fn commit_change_ids(&self) -> Box<dyn Iterator<Item = (CommitId, ChangeId)> + '_>;
+
     fn iter_graph(&self) -> Box<dyn Iterator<Item = (CommitId, Vec<RevsetGraphEdge>)> + '_>;
 
     fn change_id_index(&self) -> Box<dyn ChangeIdIndex + 'index>;