rewrite: pass CommitRewriter into rebase_commit_with_options()

`CommitRewriter` wraps 3 of the arguments, so I think it makes sense
to pass it instead. More importantly, I hope to continue refactoring
so many of the callers already have a `CommitRewriter`.

cli/src/commands/rebase.rs

@@ -25,7 +25,9 @@ use jj_lib::commit::{Commit, CommitIteratorExt};
 use jj_lib::object_id::ObjectId;
 use jj_lib::repo::{ReadonlyRepo, Repo};
 use jj_lib::revset::{RevsetExpression, RevsetIteratorExt};
-use jj_lib::rewrite::{rebase_commit, rebase_commit_with_options, EmptyBehaviour, RebaseOptions};
+use jj_lib::rewrite::{
+    rebase_commit, rebase_commit_with_options, CommitRewriter, EmptyBehaviour, RebaseOptions,
+};
 use jj_lib::settings::UserSettings;
 use tracing::instrument;
 
@@ -292,16 +294,15 @@ pub fn rebase_descendants(
     rebase_options: RebaseOptions,
 ) -> Result<usize, CommandError> {
     for old_commit in old_commits.iter() {
-        rebase_commit_with_options(
-            settings,
+        let rewriter = CommitRewriter::new(
             tx.mut_repo(),
             old_commit.borrow().clone(),
             new_parents
                 .iter()
                 .map(|parent| parent.id().clone())
                 .collect(),
-            &rebase_options,
-        )?;
+        );
+        rebase_commit_with_options(settings, rewriter, &rebase_options)?;
     }
     let num_rebased = old_commits.len()
         + tx.mut_repo()

lib/src/rewrite.rs

@@ -99,13 +99,8 @@ pub fn rebase_commit(
     old_commit: Commit,
     new_parents: Vec<CommitId>,
 ) -> BackendResult<Commit> {
-    let rebased_commit = rebase_commit_with_options(
-        settings,
-        mut_repo,
-        old_commit,
-        new_parents,
-        &Default::default(),
-    )?;
+    let rewriter = CommitRewriter::new(mut_repo, old_commit, new_parents);
+    let rebased_commit = rebase_commit_with_options(settings, rewriter, &Default::default())?;
     match rebased_commit {
         RebasedCommit::Rewritten(new_commit) => Ok(new_commit),
         RebasedCommit::Abandoned { parent: _ } => panic!("Commit was unexpectedly abandoned"),
@@ -247,13 +242,9 @@ pub enum RebasedCommit {
 
 pub fn rebase_commit_with_options(
     settings: &UserSettings,
-    mut_repo: &mut MutableRepo,
-    old_commit: Commit,
-    new_parents: Vec<CommitId>,
+    mut rewriter: CommitRewriter<'_>,
     options: &RebaseOptions,
 ) -> BackendResult<RebasedCommit> {
-    let mut rewriter = CommitRewriter::new(mut_repo, old_commit, new_parents);
-
     // If specified, don't create commit where one parent is an ancestor of another.
     if options.simplify_ancestor_merge {
         rewriter.simplify_ancestor_merge();
@@ -396,13 +387,9 @@ impl<'settings, 'repo> DescendantRebaser<'settings, 'repo> {
             return Ok(());
         }
 
-        let rebased_commit: RebasedCommit = rebase_commit_with_options(
-            self.settings,
-            self.mut_repo,
-            old_commit,
-            new_parent_ids,
-            &self.options,
-        )?;
+        let rewriter = CommitRewriter::new(self.mut_repo, old_commit, new_parent_ids);
+        let rebased_commit: RebasedCommit =
+            rebase_commit_with_options(self.settings, rewriter, &self.options)?;
         let new_commit = match rebased_commit {
             RebasedCommit::Rewritten(new_commit) => new_commit,
             RebasedCommit::Abandoned { parent } => parent,

lib/tests/test_rewrite.rs

@@ -19,7 +19,9 @@ use jj_lib::merged_tree::MergedTree;
 use jj_lib::op_store::{RefTarget, RemoteRef, RemoteRefState, WorkspaceId};
 use jj_lib::repo::Repo;
 use jj_lib::repo_path::RepoPath;
-use jj_lib::rewrite::{rebase_commit_with_options, restore_tree, EmptyBehaviour, RebaseOptions};
+use jj_lib::rewrite::{
+    rebase_commit_with_options, restore_tree, CommitRewriter, EmptyBehaviour, RebaseOptions,
+};
 use maplit::{hashmap, hashset};
 use test_case::test_case;
 use testutils::{
@@ -1726,14 +1728,8 @@ fn test_rebase_abandoning_empty() {
         empty: EmptyBehaviour::AbandonAllEmpty,
         simplify_ancestor_merge: true,
     };
-    rebase_commit_with_options(
-        &settings,
-        tx.mut_repo(),
-        commit_b,
-        vec![commit_b2.id().clone()],
-        &rebase_options,
-    )
-    .unwrap();
+    let rewriter = CommitRewriter::new(tx.mut_repo(), commit_b, vec![commit_b2.id().clone()]);
+    rebase_commit_with_options(&settings, rewriter, &rebase_options).unwrap();
     let rebase_map = tx
         .mut_repo()
         .rebase_descendants_with_options_return_map(&settings, rebase_options)