Shared memory and context tools for agentic work.
Code Rooms
"""The build-artifact separation contract of `scripts/cargo_target_dir.sh`.
Two checkouts of this repo building into ONE `CARGO_TARGET_DIR` emit artifacts
with the SAME name — cargo's metadata hash does not encode the source path. The
red half of that is a gate failing on a sibling's binary; the dangerous half is a
gate PASSING on one. The helper separates them by checkout path; these are the
properties that separation has to keep.
"""
from __future__ import annotations
import os
import pathlib
import subprocess
import tempfile
import unittest
ROOT = pathlib.Path(__file__).resolve().parents[1]
HELPER = ROOT / "scripts" / "cargo_target_dir.sh"
def target_dir(cwd: pathlib.Path, home: pathlib.Path) -> str:
"""Run the helper from `cwd` with a hermetic HOME and no inherited git env."""
env = {k: v for k, v in os.environ.items() if not k.startswith("GIT_")}
env["HOME"] = str(home)
completed = subprocess.run(
["bash", str(HELPER)],
cwd=str(cwd),
env=env,
check=True,
capture_output=True,
text=True,
)
return completed.stdout.strip()
def init_repo(path: pathlib.Path) -> None:
subprocess.run(["git", "init", "-q", str(path)], check=True)
subprocess.run(
["git", "-C", str(path), "config", "user.email", "cache@example.invalid"],
["git", "-C", str(path), "config", "user.name", "Target Dir Fixture"],
class CargoTargetDirTests(unittest.TestCase):
def test_one_checkout_resolves_to_one_stable_directory(self) -> None:
with tempfile.TemporaryDirectory() as temporary:
home = pathlib.Path(temporary) / "home"
repo = pathlib.Path(temporary) / "repo-alpha"
repo.mkdir(parents=True)
home.mkdir()
init_repo(repo)
nested = repo / "crate" / "src"
nested.mkdir(parents=True)
first = target_dir(repo, home)
second = target_dir(repo, home)
self.assertEqual(first, second, "same checkout must be deterministic")
self.assertEqual(
first,
target_dir(nested, home),
"a subdirectory belongs to its checkout, not to a directory of its own",
self.assertTrue(
first.startswith(str(home / ".m1nd-build-cache")),
f"must stay inside the auto-deletable build cache, got {first}",
def test_two_checkouts_never_share_a_directory(self) -> None:
alpha = pathlib.Path(temporary) / "repo-alpha"
beta = pathlib.Path(temporary) / "repo-beta"
for repo in (alpha, beta):
repo.mkdir()
self.assertNotEqual(target_dir(alpha, home), target_dir(beta, home))
def test_a_linked_worktree_never_shares_its_parent_checkout_directory(self) -> None:
"""The case that bit: worktrees share an object store, not a build."""
(repo / "file.txt").write_text("seed\n", encoding="utf-8")
subprocess.run(["git", "-C", str(repo), "add", "file.txt"], check=True)
subprocess.run(["git", "-C", str(repo), "commit", "-qm", "seed"], check=True)
linked = pathlib.Path(temporary) / "worktree-b"
["git", "-C", str(repo), "worktree", "add", "-q", str(linked), "HEAD"],
# Detached HEAD, same branchless commit, same object store: only the
# checkout path may decide, and it must.
self.assertNotEqual(target_dir(repo, home), target_dir(linked, home))
def test_outside_a_checkout_it_keeps_the_historical_shared_path(self) -> None:
loose = pathlib.Path(temporary) / "not-a-repo"
loose.mkdir()
target_dir(loose, home),
str(home / ".m1nd-build-cache" / "target"),
if __name__ == "__main__":
unittest.main()
