Merge unseen-fetch-bulk: full-objects clone, no per-blob lazy fetch

Co-Authored-By: Claude Opus 4.8 <[email protected]>

benchmarks/unseen/README.md

@@ -101,11 +101,14 @@ passing implementation tests does not assert that 300 eligible repositories exis
 Clones and checkpoints default to `results_root()/unseen-draft` (normally
 `~/ousast-results/plane/unseen-draft`), overridable by `--cache /outside/path`.
 The cache cannot lie inside `--root`. One opaque, disposable clone exists at a time;
-it is removed on success, rejection, or failure. `--filter=blob:none --no-checkout`
+it is removed on success, rejection, or failure. A full-objects `--no-checkout` clone
-keeps the commit graph needed for temporal thirds, blame, and release-tag ancestry,
+brings the whole commit graph and every blob in one pack, so temporal thirds, blame,
-and fetches source blobs on demand. This is a **partial clone**, not a shallow history.
+and release-tag ancestry read locally; `--no-checkout` still skips the working tree.
-The 500 MiB disk cap is checked after Git commands, including lazy blob fetches;
+This is a full clone, not a shallow history, and has no blob:none promisor, so a
-one in-flight command can transiently exceed it before rejection and cleanup.
+genuinely missing object errors loudly instead of silently round-tripping (the old
+promisor path fetched blobs one at a time, hundreds of round-trips per repo). The
+500 MiB disk cap is checked after Git commands; one in-flight command can transiently
+exceed it before rejection and cleanup.
 Git output is captured, never forwarded. Each repository must read a nonempty source
 blob before extraction. Summary instrumentation includes source read operations and
 actual bytes, clone count, cumulative/peak disk bytes, wall time, and logical API calls

benchmarks/unseen/draft.py

@@ -166,9 +166,14 @@ class Clones:
             git = Git(path, runner=self.runner, limit_bytes=self.limit_bytes, deadline_seconds=self.deadline_seconds)
             try:
                 # Full commit graph is needed for temporal thirds and OSV brackets.
-                # Content reads fetch blobs on demand through Git's promisor mechanism.
+                # A full-objects clone (no blob:none promisor) brings every blob in
+                # one pack, so blame/log/diff read locally instead of fetching each
+                # blob on demand (the old promisor path cost ~hundreds of round-trips
+                # per repo). --no-checkout still skips the working tree. With no
+                # promisor remote, a genuinely missing object errors loudly rather
+                # than silently round-tripping. Disk is bounded by limit_bytes below.
                 done = self.runner(
-                    ["git", "-c", "credential.helper=", "clone", "--quiet", "--filter=blob:none", "--no-checkout", url, str(path)],
+                    ["git", "-c", "credential.helper=", "clone", "--quiet", "--no-checkout", url, str(path)],
                     stdin=subprocess.DEVNULL,
                     stdout=subprocess.PIPE,
                     stderr=subprocess.PIPE,
@@ -229,7 +234,7 @@ def repository_changes(git, candidate, fixes: set[str], *, seed: int):
                 # Extra advisory fixes are best-effort exclusions. The candidate
                 # was fetched strictly by extract_repository. Do not import extra
                 # tags before introducing() checks the candidate's version bracket.
-                git.run("fetch", "--quiet", "--no-tags", "--filter=blob:none", "origin", fix)
+                git.run("fetch", "--quiet", "--no-tags", "origin", fix)
             resolved.append(git.run("rev-parse", fix).strip())
         except InstrumentFailure as exc:
             if fix == candidate.fix or not str(exc).startswith("git_exit_"):
@@ -325,7 +330,7 @@ def extract_repository(candidate, github, clones, fixes, seed):
     try:
         with extract.process_deadline(total):
             with clones.open(candidate.url) as git:
-                git.run("fetch", "--quiet", "--filter=blob:none", "origin", candidate.fix)
+                git.run("fetch", "--quiet", "origin", candidate.fix)
                 changes, exclusions, proof = repository_changes(git, candidate, fixes, seed=seed)
                 entry = {**asdict(candidate), "changes": changes, "instrument": proof}
             result = {"entry": entry, "ordinary_exclusions": exclusions}

tests/test_unseen_draft.py

@@ -100,7 +100,11 @@ def test_cache_is_outside_repository_deleted_and_partial(tmp_path):
         assert git.path.exists()
         clone_path = git.path
     assert not clone_path.exists()
-    assert "--filter=blob:none" in calls[0] and "--no-checkout" in calls[0]
+    # Full-objects clone: no blob:none promisor (which caused per-blob lazy
+    # fetches), so every blob arrives in one pack and a missing object errors
+    # loudly. --no-checkout still skips the working tree.
+    assert "--filter=blob:none" not in calls[0] and "--no-checkout" in calls[0]
+    assert "clone" in calls[0]
     assert clones.counts["clones"] == 1 and clones.counts["clone_bytes"] == 3