From dbf2a98903abbeefe75a16399eb1378ea2f59345 Mon Sep 17 00:00:00 2001
From: Martin von Zweigbergk <martinvonz@google.com>
Date: Sun, 28 Apr 2024 10:40:12 -0700
Subject: [PATCH] rewrite: add `CommitRewriter::record_abandoned_commit()`

We already have two uses for this function and I think we're soon
going to have more.

The function record the old commit as abandoned with the new parents,
which is typically what you want. We could record it as abandoned with
the old parents instead but then we'd have to do an extra iteration to
find the parents when rebasing any children. It would also be
confusing if
`rewriter.set_parents(new_parents).record_abandoned_commit()` didn't
respect the new parents.
---
 lib/src/rewrite.rs                  | 13 +++++++++----
 lib/tests/test_rewrite_transform.rs |  6 +-----
 2 files changed, 10 insertions(+), 9 deletions(-)

diff --git a/lib/src/rewrite.rs b/lib/src/rewrite.rs
index 6915cb5bd..9e4b1c5ec 100644
--- a/lib/src/rewrite.rs
+++ b/lib/src/rewrite.rs
@@ -184,6 +184,14 @@ impl<'repo> CommitRewriter<'repo> {
         self.new_parents.retain(|parent| head_set.contains(parent));
     }
 
+    /// Records the old commit as abandoned with the new parents.
+    pub fn abandon(self) {
+        let old_commit_id = self.old_commit.id().clone();
+        let new_parents = self.new_parents;
+        self.mut_repo
+            .record_abandoned_commit_with_parents(old_commit_id, new_parents);
+    }
+
     /// Rebase the old commit onto the new parents. Returns a `CommitBuilder`
     /// for the new commit. Returns `None` if the commit was abandoned.
     pub fn rebase_with_empty_behavior(
@@ -235,10 +243,7 @@ impl<'repo> CommitRewriter<'repo> {
                 EmptyBehaviour::AbandonAllEmpty => *parent.tree_id() == new_tree_id,
             };
             if should_abandon {
-                self.mut_repo.record_abandoned_commit_with_parents(
-                    self.old_commit.id().clone(),
-                    std::iter::once(parent.id().clone()),
-                );
+                self.abandon();
                 return Ok(None);
             }
         }
diff --git a/lib/tests/test_rewrite_transform.rs b/lib/tests/test_rewrite_transform.rs
index 58ebc7e76..87daa9775 100644
--- a/lib/tests/test_rewrite_transform.rs
+++ b/lib/tests/test_rewrite_transform.rs
@@ -50,11 +50,7 @@ fn test_transform_descendants_sync() {
         .transform_descendants(&settings, vec![commit_b.id().clone()], |mut rewriter| {
             rewriter.replace_parent(commit_a.id(), [commit_g.id()]);
             if *rewriter.old_commit() == commit_c {
-                let old_id = rewriter.old_commit().id().clone();
-                let new_parent_ids = rewriter.new_parents().to_vec();
-                rewriter
-                    .mut_repo()
-                    .record_abandoned_commit_with_parents(old_id, new_parent_ids);
+                rewriter.abandon();
             } else {
                 let old_commit_id = rewriter.old_commit().id().clone();
                 let new_commit = rewriter.rebase(&settings)?.write()?;