Remove the four-GiB performance fixture compatibility helper

The package controllers use generate-jsonl, verify, capacity-reflink and sample;
only a unit test still called the old generate helper. The test now uses
fixture_records directly.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

e2e/physical_performance_fixture.py

@@ -48,12 +48,6 @@ def fixture_records(directory, case, size_gib=4):
         yield {"name": path.name, "size": size, "sha256": digest.hexdigest()}
 
 
-def generate(directory, case):
-    # Compatibility for the original four-GiB helper; long runs use JSON Lines.
-    return {row["name"]: {"size": row["size"], "sha256": row["sha256"]}
-            for row in fixture_records(directory, case)}
-
-
 def generate_jsonl(directory, case, size_gib, manifest):
     if Path(directory).resolve() in Path(manifest).resolve().parents:
         raise ValueError("Fixture manifest must remain outside the selected source directory")
@@ -241,9 +235,7 @@ def sample(tape_directory, pages=("34", "0C")):
 
 if __name__ == "__main__":
     command, *arguments = sys.argv[1:]
-    if command == "generate":
-        output = generate(*arguments)
-    elif command == "generate-jsonl":
+    if command == "generate-jsonl":
         output = generate_jsonl(*arguments)
     elif command == "capacity-reflink":
         output = capacity_reflink(arguments[0], json.loads(arguments[1]))

e2e/test_physical_performance.py

@@ -90,8 +90,8 @@ class PerformanceFixtureTests(unittest.TestCase):
     def test_deterministic_fixture_and_batched_restore_check(self):
         with tempfile.TemporaryDirectory() as root, mock.patch.dict(fixture.MATRIX, {"tiny": (2, 256 * 1024, True)}):
             first, second = Path(root) / "one", Path(root) / "two"
-            manifest = fixture.generate(first, "tiny")
-            self.assertEqual(fixture.generate(second, "tiny"), manifest)
+            manifest = {row["name"]: {"size": row["size"], "sha256": row["sha256"]} for row in fixture.fixture_records(first, "tiny")}
+            self.assertEqual([row["sha256"] for row in fixture.fixture_records(second, "tiny")], [value["sha256"] for value in manifest.values()])
             for name, expected in manifest.items():
                 data = (first / name).read_bytes()
                 self.assertEqual(len(data), expected["size"])