From 5a32118af1ff3e44c7aa8acbb6cc7ade04d0ac07 Mon Sep 17 00:00:00 2001
From: Martin von Zweigbergk <martinvonz@google.com>
Date: Fri, 26 Feb 2021 23:37:42 -0800
Subject: [PATCH] repo: move creation of OpStore out of View

We want to support loading the repo at a specific operation without
first loading the head operation (like we currently do). One reason
for that is of course efficiency. A possibly more important reason is
that the head operation may be conflicted, depending on how we decide
to deal with operation-level conflicts. In order to do that, it makes
sense to move the creation of the `OpStore` outside of the
`View`. That also suggests that the `.jj/view/op_store/` directory
should move to `.jj/op_store/`, so this patch also does that. That's
consistent with how `.jj/store/` is outside of `.jj/working_copy/`.
---
 lib/src/repo.rs |  9 ++++++++-
 lib/src/view.rs | 14 +++++++-------
 2 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/lib/src/repo.rs b/lib/src/repo.rs
index 3995d207a..dde5180f0 100644
--- a/lib/src/repo.rs
+++ b/lib/src/repo.rs
@@ -26,8 +26,10 @@ use crate::evolution::{EvolutionRef, MutableEvolution, ReadonlyEvolution};
 use crate::git_store::GitStore;
 use crate::index::{IndexRef, MutableIndex, ReadonlyIndex};
 use crate::local_store::LocalStore;
+use crate::op_store::OpStore;
 use crate::operation::Operation;
 use crate::settings::{RepoSettings, UserSettings};
+use crate::simple_op_store::SimpleOpStore;
 use crate::store;
 use crate::store::{Store, StoreError};
 use crate::store_wrapper::StoreWrapper;
@@ -191,8 +193,12 @@ impl ReadonlyRepo {
             is_pruned: false,
         };
         let checkout_commit = store.write_commit(checkout_commit);
+
+        std::fs::create_dir(repo_path.join("op_store")).unwrap();
+        let op_store: Arc<dyn OpStore> = Arc::new(SimpleOpStore::init(repo_path.join("op_store")));
         let view = ReadonlyView::init(
             store.clone(),
+            op_store,
             repo_path.join("view"),
             checkout_commit.id().clone(),
         );
@@ -254,7 +260,8 @@ impl ReadonlyRepo {
             wc_path.clone(),
             repo_path.join("working_copy"),
         );
-        let view = ReadonlyView::load(store.clone(), repo_path.join("view"));
+        let op_store: Arc<dyn OpStore> = Arc::new(SimpleOpStore::load(repo_path.join("op_store")));
+        let view = ReadonlyView::load(store.clone(), op_store, repo_path.join("view"));
         let repo = ReadonlyRepo {
             repo_path,
             wc_path,
diff --git a/lib/src/view.rs b/lib/src/view.rs
index 0c0cf3ffd..430ac1fdd 100644
--- a/lib/src/view.rs
+++ b/lib/src/view.rs
@@ -26,7 +26,6 @@ use crate::lock::FileLock;
 use crate::op_store;
 use crate::op_store::{OpStore, OpStoreResult, OperationId, OperationMetadata};
 use crate::operation::Operation;
-use crate::simple_op_store::SimpleOpStore;
 use crate::store::{CommitId, Timestamp};
 use crate::store_wrapper::StoreWrapper;
 
@@ -361,10 +360,12 @@ fn merge_op_heads(
 }
 
 impl ReadonlyView {
-    pub fn init(store: Arc<StoreWrapper>, path: PathBuf, checkout: CommitId) -> Self {
-        std::fs::create_dir(path.join("op_store")).unwrap();
-
-        let op_store = Arc::new(SimpleOpStore::init(path.join("op_store")));
+    pub fn init(
+        store: Arc<StoreWrapper>,
+        op_store: Arc<dyn OpStore>,
+        path: PathBuf,
+        checkout: CommitId,
+    ) -> Self {
         let mut root_view = op_store::View::new(checkout.clone());
         root_view.head_ids.insert(checkout);
         let root_view_id = op_store.write_view(&root_view).unwrap();
@@ -389,8 +390,7 @@ impl ReadonlyView {
         }
     }
 
-    pub fn load(store: Arc<StoreWrapper>, path: PathBuf) -> Self {
-        let op_store: Arc<dyn OpStore> = Arc::new(SimpleOpStore::load(path.join("op_store")));
+    pub fn load(store: Arc<StoreWrapper>, op_store: Arc<dyn OpStore>, path: PathBuf) -> Self {
         let op_heads_dir = path.join("op_heads");
         let (op_id, _operation, view) =
             get_single_op_head(&store, &op_store, &op_heads_dir).unwrap();