tests: add lance_surface_guards pre-flight pins for the v6 bump

Land 8 named guards in a new test file that pin Lance API surfaces
OmniGraph relies on. Each guard turns a silent-break risk (variant
rename, struct restructure, async-flip) into a red CI bar instead of
runtime drift.

Guards (mapped to the silent-break inventory from the v6 migration plan):

  Runtime (#[tokio::test]):
  1. lance_error_too_much_write_contention_variant_exists — pins the
     variant referenced by db/manifest/publisher.rs::map_lance_publish_error.
  2. manifest_location_field_shape — pins .path/.size/.e_tag/.naming_scheme
     types and ManifestLocation accessor returning &Self (the access
     pattern at db/manifest/metadata.rs:84-88).
  6. write_params_default_does_not_set_storage_version — confirms our
     explicit V2_2 pin remains load-bearing (blob v2 requirement).

  Compile-only async fns (#[allow(...)] + unimplemented!() placeholders;
  never run, but cargo build --tests enforces the API shape):
  3. checkout_version + restore chain — pins the recovery rollback hammer
     at db/manifest/recovery.rs:505-522.
  4. DatasetBuilder::from_namespace().with_branch().with_version().load()
     — pins the namespace builder chain at db/manifest/namespace.rs:162-174.
  5. MergeInsertBuilder fluent chain — pins the manifest CAS at
     db/manifest/publisher.rs:370-391, including the return shape
     (Arc<Dataset>, MergeStats).
  7. compact_files(&mut ds, CompactionOptions, None) — pins
     db/omnigraph/optimize.rs:107.
  8. DeleteResult { new_dataset, num_deleted_rows } — pins the inline
     delete result shape (MR-A will repurpose this guard to the staged
     two-phase variant once Lance #6658 migration lands).

This is commit 1 of the chore/lance-6.0.1 migration. Cargo bump
follows in commit 2 (will trigger the guards under v6 if any surface
drifted).

Per the migration plan at ~/.claude/plans/shimmering-percolating-duckling.md
(written this session). Two guards from the plan deferred to follow-up:
  - manifest_cas_returns_row_level_contention_variant (full publisher
    race integration test — needs harness scaffolding)
  - table_version_metadata_byte_compatible_with_v4 (TableVersionMetadata
    is pub(crate); requires test reach extension).

Verified on v4: cargo test -p omnigraph-engine --test lance_surface_guards
passes 3/3 runtime tests; cargo build -p omnigraph-engine --tests
compiles all 5 compile-only guards clean.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
This commit is contained in:
aaltshuler 2026-05-22 20:00:33 +01:00
parent e1b40aee0b
commit d571fa8b0b

View file

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//! Lance API surface guards.
//!
//! Each guard pins a Lance API surface that OmniGraph relies on. If a future
//! Lance bump silently renames a variant, restructures a public struct, or
//! flips a method to async, the corresponding guard either fails to compile
//! (compile-time guards) or fails at runtime (runtime guards). The purpose
//! is to turn silent-break risks into red CI bars on the *next* Lance bump,
//! rather than into wrong-state recovery in production.
//!
//! Pair this file with `docs/dev/lance.md`'s alignment audit stanza: any
//! Lance bump runs `cargo test -p omnigraph-engine --test lance_surface_guards`
//! first as the smoke check.
//!
//! ## Compile-only guards
//!
//! Functions prefixed with `_compile_` are gated `#[allow(dead_code, unreachable_code, unused_variables, unused_mut)]`
//! and never called. They exist to make `cargo build -p omnigraph-engine --tests`
//! enforce the API shape. Using `unimplemented!()` as a placeholder lets type
//! inference proceed without running anything.
//!
//! ## Runtime guards
//!
//! Functions decorated `#[tokio::test]` actually run; they construct real
//! values and assert field shapes / types.
use std::sync::Arc;
use arrow_array::{Int32Array, RecordBatch, RecordBatchIterator, StringArray};
use arrow_schema::{DataType, Field, Schema};
use lance::Dataset;
use lance::dataset::builder::DatasetBuilder;
use lance::dataset::optimize::{CompactionOptions, compact_files};
use lance::dataset::write::delete::DeleteResult;
use lance::dataset::{MergeInsertBuilder, WhenMatched, WhenNotMatched, WriteMode, WriteParams};
use lance_file::version::LanceFileVersion;
use lance_namespace::LanceNamespace;
use lance_table::io::commit::ManifestNamingScheme;
/// Helper: build a small fresh dataset in a tempdir. Pinned at V2_2 to match
/// production write paths (blob v2 requires V2_2; see `docs/dev/lance.md`).
async fn fresh_dataset(uri: &str) -> Dataset {
let schema = Arc::new(Schema::new(vec![
Field::new("id", DataType::Utf8, false),
Field::new("value", DataType::Int32, false),
]));
let batch = RecordBatch::try_new(
schema.clone(),
vec![
Arc::new(StringArray::from(vec!["alice", "bob"])),
Arc::new(Int32Array::from(vec![1, 2])),
],
)
.unwrap();
let reader = RecordBatchIterator::new(vec![Ok(batch)], schema);
let params = WriteParams {
mode: WriteMode::Create,
enable_stable_row_ids: true,
data_storage_version: Some(LanceFileVersion::V2_2),
..Default::default()
};
Dataset::write(reader, uri, Some(params)).await.unwrap()
}
// --- Guard 1: LanceError::TooMuchWriteContention variant exists ------------
//
// `db/manifest/publisher.rs::map_lance_publish_error` pattern-matches on this
// variant to surface typed `OmniError::ManifestRowLevelCasContention`. If
// Lance renames the variant or removes the builder, this guard fails.
#[tokio::test]
async fn lance_error_too_much_write_contention_variant_exists() {
let err = lance::Error::too_much_write_contention("guard");
assert!(
matches!(err, lance::Error::TooMuchWriteContention { .. }),
"Lance::Error::TooMuchWriteContention variant missing or renamed; \
update db/manifest/publisher.rs::map_lance_publish_error and \
this guard, then re-pin docs/dev/lance.md."
);
}
// --- Guard 2: ManifestLocation field shape ---------------------------------
//
// `db/manifest/metadata.rs:84-88` reads `.path`, `.size`, `.e_tag`,
// `.naming_scheme` off `dataset.manifest_location()`. If any field renames
// or changes type, this guard fails to compile.
#[tokio::test]
async fn manifest_location_field_shape() {
let dir = tempfile::tempdir().unwrap();
let uri = dir.path().join("guard.lance");
let ds = fresh_dataset(uri.to_str().unwrap()).await;
let loc = ds.manifest_location();
// Explicit type bindings — these are the load-bearing assertions. If a
// type drifts (e.g. .size: Option<u64> → .size: u64), this fails to
// compile.
let _path: &object_store::path::Path = &loc.path;
let _size: Option<u64> = loc.size;
let _e_tag: Option<String> = loc.e_tag.clone();
let _scheme: ManifestNamingScheme = loc.naming_scheme;
// Runtime sanity — naming_scheme should produce a Debug string we use
// verbatim in `TableVersionMetadata::naming_scheme`.
assert!(!format!("{:?}", loc.naming_scheme).is_empty());
}
// --- Guard 3: checkout_version + restore async chain -----------------------
//
// `db/manifest/recovery.rs:505-522` chains `Dataset::open(...).await?
// .checkout_version(N).await?.restore().await?` as the recovery rollback
// hammer. Compile-only — never runs.
#[allow(dead_code, unreachable_code, unused_variables, unused_mut)]
async fn _compile_checkout_version_then_restore_signature() -> lance::Result<()> {
let ds: Dataset = unimplemented!();
let mut ds: Dataset = ds.checkout_version(1u64).await?;
// `restore()` takes `&mut self` and returns `Result<()>`; the dataset
// mutates in place. If Lance flips this to return a fresh `Dataset`
// (consuming `self`), this guard fails to compile.
let _: () = ds.restore().await?;
Ok(())
}
// --- Guard 4: DatasetBuilder::from_namespace fluent chain ------------------
//
// `db/manifest/namespace.rs:162-174` chains
// `DatasetBuilder::from_namespace(ns, vec![id]).await?.with_branch(...).with_version(...).load().await?`.
// Compile-only.
#[allow(dead_code, unreachable_code, unused_variables, unused_mut)]
async fn _compile_dataset_builder_from_namespace_signature(
ns: Arc<dyn LanceNamespace>,
) -> lance::Result<()> {
let builder: DatasetBuilder =
DatasetBuilder::from_namespace(ns, vec!["table".to_string()]).await?;
let builder: DatasetBuilder = builder.with_branch("b", None);
let builder: DatasetBuilder = builder.with_version(1u64);
let _ds: Dataset = builder.load().await?;
Ok(())
}
// --- Guard 5: MergeInsertBuilder fluent chain ------------------------------
//
// `db/manifest/publisher.rs:370-391` is the manifest CAS. If any method on
// the builder renames or changes signature, the publisher silently breaks.
// Compile-only.
#[allow(dead_code, unreachable_code, unused_variables, unused_mut)]
async fn _compile_merge_insert_builder_method_chain() -> lance::Result<()> {
use lance::dataset::MergeStats;
let ds: Arc<Dataset> = unimplemented!();
let job = MergeInsertBuilder::try_new(ds, vec!["object_id".to_string()])?
.when_matched(WhenMatched::UpdateAll)
.when_not_matched(WhenNotMatched::InsertAll)
.conflict_retries(0)
.use_index(false)
.try_build()?;
// execute_reader takes `impl StreamingWriteSource` (lance trait), which
// RecordBatchIterator implements. Pin the return shape
// `(Arc<Dataset>, MergeStats)` — the publisher's CAS loop depends on
// both: the new Dataset to advance HEAD, the stats for the audit row.
let source: RecordBatchIterator<Vec<Result<RecordBatch, arrow_schema::ArrowError>>> =
unimplemented!();
let result: (Arc<Dataset>, MergeStats) = job.execute_reader(source).await?;
let _ds: Arc<Dataset> = result.0;
let _stats: MergeStats = result.1;
Ok(())
}
// --- Guard 6: WriteParams::default() leaves data_storage_version = None ----
//
// Our V2_2 pin is load-bearing for blob v2 (verified earlier this session
// when V2_1 produced "Blob v2 requires file version >= 2.2" on 13 blob
// tests). If Lance changes the default to pin some version itself, audit
// every `data_storage_version: Some(LanceFileVersion::V2_2)` site.
#[test]
fn write_params_default_does_not_set_storage_version() {
let params = WriteParams::default();
assert_eq!(
params.data_storage_version, None,
"WriteParams::default().data_storage_version is no longer None; \
audit every explicit V2_2 pin (see rg 'LanceFileVersion::V2_2')."
);
}
// --- Guard 7: compact_files signature --------------------------------------
//
// `db/omnigraph/optimize.rs:107` calls `compact_files(&mut ds, options, None)`.
// Compile-only.
#[allow(dead_code, unreachable_code, unused_variables, unused_mut)]
async fn _compile_compact_files_signature() -> lance::Result<()> {
let mut ds: Dataset = unimplemented!();
let options: CompactionOptions = CompactionOptions::default();
let _metrics = compact_files(&mut ds, options, None).await?;
Ok(())
}
// --- Guard 8: Dataset::delete returns DeleteResult { new_dataset, num_deleted_rows } ---
//
// `table_store.rs::delete_where` consumes both fields. When MR-A migrates
// `delete_where` to two-phase via `DeleteBuilder::execute_uncommitted`, this
// guard updates to pin the staged path. Compile-only.
#[allow(dead_code, unreachable_code, unused_variables, unused_mut)]
async fn _compile_delete_result_field_shape() -> lance::Result<()> {
let mut ds: Dataset = unimplemented!();
let result: DeleteResult = ds.delete("x = 1").await?;
let _new_dataset: Arc<Dataset> = result.new_dataset;
let _num_deleted: u64 = result.num_deleted_rows;
Ok(())
}