feat: add local diff review workflow

tests/repository.rs

@@ -195,6 +195,75 @@ fn disk_state(root: &Path) -> BTreeMap<PathBuf, (u32, Vec<u8>)> {
     result
 }
 
+#[test]
+fn comparison_revisions_freeze_commits_and_address_working_contents() {
+    for kind in [RepoKind::Git, RepoKind::Jujutsu] {
+        let fixture = Fixture::new();
+        let root = fixture.dir("identity").canonicalize().unwrap();
+        match kind {
+            RepoKind::Git => init_git(&root),
+            RepoKind::Jujutsu => init_jj(&root, false),
+        }
+        fs::write(root.join("file"), "committed\n").unwrap();
+        let id = match kind {
+            RepoKind::Git => {
+                git(&root, &["add", "."]);
+                git(&root, &["commit", "-m", "baseline"]);
+                git(&root, &["rev-parse", "HEAD"])
+            }
+            RepoKind::Jujutsu => {
+                jj(&root, &["describe", "-m", "baseline"]);
+                jj(&root, &["log", "--no-graph", "-r", "@", "-T", "commit_id"])
+            }
+        };
+        fs::write(root.join("file"), "working\n").unwrap();
+        let state = disk_state(&root);
+        let before = revision(&id, kind);
+        let after = working(kind);
+        let mut repository = open(&root);
+        let first = repository
+            .compare(1, &before, &after, ComparisonMode::Snapshots, &[])
+            .unwrap();
+        assert_eq!(first.revisions[0], id);
+        assert!(first.revisions[1].starts_with("working:"));
+        let reopened = open(&root)
+            .compare(2, &before, &after, ComparisonMode::Snapshots, &[])
+            .unwrap();
+        assert_eq!(first.revisions, reopened.revisions);
+        let overlay = repository
+            .compare(
+                3,
+                &before,
+                &after,
+                ComparisonMode::Snapshots,
+                &[(root.join("file"), "unsaved\n".into())],
+            )
+            .unwrap();
+        assert_ne!(overlay.revisions[1], first.revisions[1]);
+        let repeated = repository
+            .compare(
+                4,
+                &before,
+                &after,
+                ComparisonMode::Snapshots,
+                &[(root.join("file"), "unsaved\n".into())],
+            )
+            .unwrap();
+        assert_eq!(repeated.revisions, overlay.revisions);
+        let working_pair = repository
+            .compare(5, &after, &after, ComparisonMode::Snapshots, &[])
+            .unwrap();
+        assert_eq!(working_pair.revisions[0], first.revisions[1]);
+        assert_eq!(working_pair.revisions[0], working_pair.revisions[1]);
+        assert_eq!(disk_state(&root), state);
+        fs::write(root.join("file"), "working").unwrap();
+        let no_newline = repository
+            .compare(6, &before, &after, ComparisonMode::Snapshots, &[])
+            .unwrap();
+        assert_ne!(no_newline.revisions[1], first.revisions[1]);
+    }
+}
+
 #[test]
 fn git_working_reads_disk_and_handles_ranges_ignored_files_binary_links_and_odd_paths() {
     let fixture = Fixture::new();
@@ -874,6 +943,7 @@ fn jj_bookmark_refresh_recomputes_branch_merge_base_and_recovers_after_deletion(
         .compare(1, before, after, ComparisonMode::BranchChanges, &[])
         .unwrap();
     assert!(original.before.ends_with(&base));
+    assert_eq!(original.revisions, [base.clone(), tip.clone()]);
     jj(&root, &["bookmark", "set", "before", "-r", &tip]);
     let Some(CheckoutRefresh::Bookmark(comparison)) =
         repository.refresh_checkout(1, 2, false, &[]).unwrap()
@@ -881,6 +951,7 @@ fn jj_bookmark_refresh_recomputes_branch_merge_base_and_recovers_after_deletion(
         panic!("Moved Before must recompute merge base");
     };
     assert!(comparison.before.ends_with(&tip));
+    assert_eq!(comparison.revisions, [tip.clone(), tip.clone()]);
     assert!(comparison.files.is_empty());
     jj(&root, &["bookmark", "delete", "after"]);
     let state = disk_state(&root);