refactor: introduce SnapshotRef type alias

[murali-db]

What changes are proposed in this pull request?

introduce SnapshotRef type alias for Arc<Snapshot>

• Fixes introduce SnapshotRef type alias for Arc<Snapshot> #1297

How was this change tested?

Existing tests.

[codecov]

Codecov Report

❌ Patch coverage is 83.33333% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 83.96%. Comparing base (e789132) to head (c0bf53d).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
ffi/src/scan.rs	0.00%	1 Missing ⚠️
kernel/src/scan/mod.rs	50.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1299      +/-   ##
==========================================
- Coverage   83.97%   83.96%   -0.02%     
==========================================
  Files         111      111              
  Lines       26250    26250              
  Branches    26250    26250              
==========================================
- Hits        22044    22041       -3     
- Misses       3109     3110       +1     
- Partials     1097     1099       +2     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[zachschuermann]

awesome, LGTM! just a quick fix in docstrings

[zachschuermann]

ah looks like some of the docs are broken due to no longer pulling in Snapshot. and btw you can test with cargo doc and/or cargo doc --open (latter is just a nice shortcut to pull up the docs we build after they are compiled)

we could just do something like add this at the bottom:

[`Snapshot::checkpoint`]: crate::Snapshot::checkpoint

[zachschuermann]

oh and I think need to peek at tests as well

[nicklan]

Looks good, but I think you missed a few spots:

kernel/examples/common/src/lib.rs
65:pub fn get_scan(snapshot: Arc<Snapshot>, args: &ScanArgs) -> DeltaResult<Option<Scan>> {

kernel/examples/write-table/src/main.rs
126:) -> DeltaResult<Arc<Snapshot>> {

kernel/src/log_compaction/tests.rs
8:fn create_mock_snapshot() -> Arc<Snapshot> {
18:fn create_multi_version_snapshot() -> Arc<Snapshot> {

kernel/src/log_compaction/writer.rs
33:    snapshot: Arc<Snapshot>,
48:        snapshot: Arc<Snapshot>,

kernel/src/snapshot/builder.rs
48:    pub(crate) fn new_from(existing_snapshot: Arc<Snapshot>) -> Self {
63:    /// Create a new [`Snapshot`]. This returns a [`SnapshotRef`] (`Arc<Snapshot>`), perhaps
70:    pub fn build(self, engine: &dyn Engine) -> DeltaResult<Arc<Snapshot>> {

[murali-db]

Looks good, but I think you missed a few spots:

kernel/examples/common/src/lib.rs
65:pub fn get_scan(snapshot: Arc<Snapshot>, args: &ScanArgs) -> DeltaResult<Option<Scan>> {

kernel/examples/write-table/src/main.rs
126:) -> DeltaResult<Arc<Snapshot>> {

kernel/src/log_compaction/tests.rs
8:fn create_mock_snapshot() -> Arc<Snapshot> {
18:fn create_multi_version_snapshot() -> Arc<Snapshot> {

kernel/src/log_compaction/writer.rs
33:    snapshot: Arc<Snapshot>,
48:        snapshot: Arc<Snapshot>,

kernel/src/snapshot/builder.rs
48:    pub(crate) fn new_from(existing_snapshot: Arc<Snapshot>) -> Self {
63:    /// Create a new [`Snapshot`]. This returns a [`SnapshotRef`] (`Arc<Snapshot>`), perhaps
70:    pub fn build(self, engine: &dyn Engine) -> DeltaResult<Arc<Snapshot>> {

looks like they were introduced during the rebase. got to them now @nicklan