From fafa9b70fccf03c00ac3b7c8513398fd634c14eb Mon Sep 17 00:00:00 2001
From: Martin von Zweigbergk <martinvonz@google.com>
Date: Sat, 17 Dec 2022 12:14:53 -0800
Subject: [PATCH] view: also merge `git_heads` when merging views

I don't know if I had just forgotten to merge `git_heads` when I added
it to the view object, but it seems like it should be merged just like
refs.
---
 lib/src/repo.rs        | 12 ++++++++++++
 lib/tests/test_view.rs |  3 +--
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/lib/src/repo.rs b/lib/src/repo.rs
index 69b5b840e..a36fbe0a6 100644
--- a/lib/src/repo.rs
+++ b/lib/src/repo.rs
@@ -39,6 +39,7 @@ use crate::op_store::{
     BranchTarget, OpStore, OperationId, OperationMetadata, RefTarget, WorkspaceId,
 };
 use crate::operation::Operation;
+use crate::refs::merge_ref_targets;
 use crate::rewrite::DescendantRebaser;
 use crate::settings::{RepoSettings, UserSettings};
 use crate::simple_op_heads_store::SimpleOpHeadsStore;
@@ -1108,6 +1109,17 @@ impl MutableRepo {
                 other_target.as_ref(),
             );
         }
+
+        if let Some(new_git_head) = merge_ref_targets(
+            self.index.as_index_ref(),
+            self.view().git_head(),
+            base.git_head(),
+            other.git_head(),
+        ) {
+            self.set_git_head(new_git_head);
+        } else {
+            self.clear_git_head();
+        }
     }
 
     /// Finds and records commits that were rewritten or abandoned between
diff --git a/lib/tests/test_view.rs b/lib/tests/test_view.rs
index 04cf07633..b131749c5 100644
--- a/lib/tests/test_view.rs
+++ b/lib/tests/test_view.rs
@@ -462,8 +462,7 @@ fn test_merge_views_git_heads() {
         removes: vec![tx0_head.id().clone()],
         adds: vec![tx1_head.id().clone(), tx2_head.id().clone()],
     };
-    // TODO: Should be equal
-    assert_ne!(repo.view().git_head(), Some(&expected_git_head));
+    assert_eq!(repo.view().git_head(), Some(&expected_git_head));
 }
 
 fn commit_transactions(settings: &UserSettings, txs: Vec<Transaction>) -> Arc<ReadonlyRepo> {