Files
hermes-agent/tests/hermes_cli/test_managed_uv.py
Jeff 1f347ee543 fix(uv): move venv aside instead of gutting it in place on Windows rebuild
hermes update can brick a Windows install. When 'hermes update --force' runs
past the concurrent-process guard, rebuild_venv runs while the venv is still in
use: shutil.rmtree(ignore_errors=True) deletes site-packages + certifi's cert
bundle but can't remove the locked python.exe, leaving a half-gutted venv that
uv venv then refuses to overwrite. Every later HTTPS call dies with
FileNotFoundError for the missing cacert and there is no recovery.

--clear alone (the c136eb4de retry path) does not fix the real lock case: when
the locked interpreter is *inside* the venv being rebuilt, neither rmtree nor
uv venv --clear can delete it. os.replace of the parent directory *is* allowed
on Windows (a running .exe is tracked by handle, not path), so we move the old
venv aside atomically to <venv>.old, rebuild with --clear in its place, and the
still-running gateway/desktop keep using the moved-aside copy until they
restart. If the venv genuinely can't be moved, we abort cleanly and leave it
fully intact; if the rebuild fails, we restore the moved-aside copy.

Folds in the call-site guards from #38511 (@f3rs3n):
- rebuild_venv() returns False (and restores the backup) if uv exits 0 without
  producing an interpreter.
- both hermes update venv-rebuild call sites abort with RuntimeError instead of
  continuing into dependency install when rebuild_venv() returns False.

Also gitignore /venv.old/ so the update autostash (git stash --include-untracked)
doesn't sweep the moved-aside venv on every run.

Root-cause fix for #37881. Supersedes the --clear-only retry from c136eb4de.

Co-authored-by: f3rs3n <32328813+f3rs3n@users.noreply.github.com>
2026-06-04 12:18:38 -04:00

272 lines
12 KiB
Python

"""Tests for hermes_cli.managed_uv — one path, no guessing."""
from __future__ import annotations
import os
import stat
from pathlib import Path
from unittest.mock import MagicMock, patch
import pytest
# ---------------------------------------------------------------------------
# Helpers
# ---------------------------------------------------------------------------
def _make_executable(path: Path) -> None:
"""Create a minimal fake uv binary at *path*."""
path.parent.mkdir(parents=True, exist_ok=True)
path.write_text("#!/bin/sh\necho uv 0.1.2\n")
path.chmod(path.stat().st_mode | stat.S_IEXEC)
# ---------------------------------------------------------------------------
# managed_uv_path
# ---------------------------------------------------------------------------
class TestManagedUvPath:
def test_posix(self, tmp_path):
with patch("hermes_cli.managed_uv.get_hermes_home", return_value=tmp_path), \
patch("hermes_cli.managed_uv.platform.system", return_value="Linux"):
from hermes_cli.managed_uv import managed_uv_path
assert managed_uv_path() == tmp_path / "bin" / "uv"
def test_windows(self, tmp_path):
with patch("hermes_cli.managed_uv.get_hermes_home", return_value=tmp_path), \
patch("hermes_cli.managed_uv.platform.system", return_value="Windows"):
from hermes_cli.managed_uv import managed_uv_path
assert managed_uv_path() == tmp_path / "bin" / "uv.exe"
# ---------------------------------------------------------------------------
# resolve_uv
# ---------------------------------------------------------------------------
class TestResolveUv:
def test_missing_returns_none(self, tmp_path):
with patch("hermes_cli.managed_uv.get_hermes_home", return_value=tmp_path):
from hermes_cli.managed_uv import resolve_uv
assert resolve_uv() is None
def test_existing_executable(self, tmp_path):
_make_executable(tmp_path / "bin" / "uv")
with patch("hermes_cli.managed_uv.get_hermes_home", return_value=tmp_path):
from hermes_cli.managed_uv import resolve_uv
result = resolve_uv()
assert result == str(tmp_path / "bin" / "uv")
def test_non_executable_file_returns_none(self, tmp_path):
uv = tmp_path / "bin" / "uv"
uv.parent.mkdir(parents=True)
uv.write_text("not a binary")
# Ensure no execute bit
uv.chmod(0o644)
with patch("hermes_cli.managed_uv.get_hermes_home", return_value=tmp_path):
from hermes_cli.managed_uv import resolve_uv
assert resolve_uv() is None
# ---------------------------------------------------------------------------
# ensure_uv
# ---------------------------------------------------------------------------
class TestEnsureUv:
def test_already_installed_no_bootstrap(self, tmp_path):
_make_executable(tmp_path / "bin" / "uv")
with patch("hermes_cli.managed_uv.get_hermes_home", return_value=tmp_path):
from hermes_cli.managed_uv import ensure_uv
path, fresh = ensure_uv()
assert path == str(tmp_path / "bin" / "uv")
assert fresh is False
def test_installs_if_missing_sets_bootstrap_flag(self, tmp_path):
with patch("hermes_cli.managed_uv.get_hermes_home", return_value=tmp_path), \
patch("hermes_cli.managed_uv._install_uv") as mock_install:
# Simulate the installer creating the binary
def fake_install(target):
_make_executable(target)
mock_install.side_effect = fake_install
from hermes_cli.managed_uv import ensure_uv
path, fresh = ensure_uv()
assert path == str(tmp_path / "bin" / "uv")
assert fresh is True
mock_install.assert_called_once()
def test_install_failure_returns_none_false(self, tmp_path):
with patch("hermes_cli.managed_uv.get_hermes_home", return_value=tmp_path), \
patch("hermes_cli.managed_uv._install_uv", side_effect=RuntimeError("network down")):
from hermes_cli.managed_uv import ensure_uv
path, fresh = ensure_uv()
assert path is None
assert fresh is False
# ---------------------------------------------------------------------------
# rebuild_venv
# ---------------------------------------------------------------------------
class TestRebuildVenv:
def test_moves_old_venv_aside_and_creates_new(self, tmp_path):
"""The old venv is moved aside to <venv>.old (never rmtree'd in place),
uv is invoked with --clear, the moved-aside backup is removed on
success, and the rebuilt interpreter is reported."""
venv_dir = tmp_path / "venv"
venv_dir.mkdir()
(venv_dir / "old_file").write_text("stale")
uv_bin = str(tmp_path / "bin" / "uv")
call_log: list[list[str]] = []
def fake_run(cmd, **kwargs):
call_log.append(list(cmd))
m = MagicMock(returncode=0, stderr="", stdout="")
if len(cmd) >= 2 and cmd[1] == "venv":
# Simulate uv creating the venv dir with a python interpreter
bin_dir = venv_dir / ("Scripts" if os.name == "nt" else "bin")
bin_dir.mkdir(parents=True, exist_ok=True)
python_name = "python.exe" if os.name == "nt" else "python"
(bin_dir / python_name).write_text("#!/bin/sh\necho Python 3.11.0")
elif "--version" in cmd:
m.stdout = "Python 3.11.0"
return m
with patch("hermes_cli.managed_uv.subprocess.run", side_effect=fake_run):
from hermes_cli.managed_uv import rebuild_venv
result = rebuild_venv(uv_bin, venv_dir)
assert result is True
# uv venv was invoked exactly once, always with --clear.
venv_calls = [c for c in call_log if len(c) >= 2 and c[1] == "venv"]
assert len(venv_calls) == 1, f"expected 1 venv call, got {venv_calls}"
assert "--clear" in venv_calls[0]
# The moved-aside backup is cleaned up after a successful rebuild.
assert not (tmp_path / "venv.old").exists()
def test_aborts_without_deleting_when_venv_in_use(self, tmp_path):
"""If os.replace fails (Windows file lock — venv in use), we must abort
cleanly WITHOUT deleting the venv and WITHOUT invoking uv."""
venv_dir = tmp_path / "venv"
venv_dir.mkdir()
(venv_dir / "locked") .write_text("held open")
uv_bin = str(tmp_path / "bin" / "uv")
call_log: list[list[str]] = []
def fake_run(cmd, **kwargs):
call_log.append(list(cmd))
return MagicMock(returncode=0, stderr="", stdout="")
with patch("hermes_cli.managed_uv.subprocess.run", side_effect=fake_run), \
patch("hermes_cli.managed_uv.os.replace", side_effect=OSError("in use")):
from hermes_cli.managed_uv import rebuild_venv
result = rebuild_venv(uv_bin, venv_dir)
assert result is False
# venv left fully intact, uv never invoked.
assert venv_dir.exists() and (venv_dir / "locked").exists()
assert [c for c in call_log if len(c) >= 2 and c[1] == "venv"] == []
def test_restores_backup_when_rebuild_fails(self, tmp_path):
"""If uv venv exits non-zero, the moved-aside venv is restored so we
never leave Hermes with no venv at all."""
venv_dir = tmp_path / "venv"
venv_dir.mkdir()
(venv_dir / "marker").write_text("original")
uv_bin = str(tmp_path / "bin" / "uv")
def fake_run(cmd, **kwargs):
return MagicMock(returncode=1, stderr="boom", stdout="")
with patch("hermes_cli.managed_uv.subprocess.run", side_effect=fake_run):
from hermes_cli.managed_uv import rebuild_venv
result = rebuild_venv(uv_bin, venv_dir)
assert result is False
# Original venv restored from the .old backup.
assert venv_dir.exists() and (venv_dir / "marker").read_text() == "original"
assert not (tmp_path / "venv.old").exists()
def test_rebuild_failure_returns_false(self, tmp_path):
venv_dir = tmp_path / "venv"
uv_bin = str(tmp_path / "bin" / "uv")
with patch("hermes_cli.managed_uv.subprocess.run") as mock_run:
mock_run.return_value = MagicMock(returncode=1, stderr="nope")
from hermes_cli.managed_uv import rebuild_venv
result = rebuild_venv(uv_bin, venv_dir)
assert result is False
def test_rebuild_success_without_python_returns_false(self, tmp_path):
"""uv can exit 0 yet leave no interpreter; that must not count as success
(guard adapted from #38511)."""
venv_dir = tmp_path / "venv"
uv_bin = str(tmp_path / "bin" / "uv")
with patch("hermes_cli.managed_uv.subprocess.run") as mock_run:
mock_run.return_value = MagicMock(returncode=0, stdout="", stderr="")
from hermes_cli.managed_uv import rebuild_venv
result = rebuild_venv(uv_bin, venv_dir)
assert result is False
# Returned before the `python --version` probe ran (only the uv venv call).
assert mock_run.call_count == 1
# ---------------------------------------------------------------------------
# update_managed_uv
# ---------------------------------------------------------------------------
class TestUpdateManagedUv:
def test_no_uv_returns_none(self, tmp_path):
with patch("hermes_cli.managed_uv.get_hermes_home", return_value=tmp_path):
from hermes_cli.managed_uv import update_managed_uv
assert update_managed_uv() is None
def test_self_update_success(self, tmp_path):
_make_executable(tmp_path / "bin" / "uv")
with patch("hermes_cli.managed_uv.get_hermes_home", return_value=tmp_path), \
patch("hermes_cli.managed_uv.subprocess.run") as mock_run:
# uv self update succeeds
mock_run.return_value = MagicMock(returncode=0, stdout="uv 0.2.0")
from hermes_cli.managed_uv import update_managed_uv
result = update_managed_uv()
assert result == str(tmp_path / "bin" / "uv")
# First call is self update, second is --version
assert mock_run.call_count == 2
assert mock_run.call_args_list[0][0][0] == [str(tmp_path / "bin" / "uv"), "self", "update"]
def test_self_update_failure_non_fatal(self, tmp_path):
_make_executable(tmp_path / "bin" / "uv")
with patch("hermes_cli.managed_uv.get_hermes_home", return_value=tmp_path), \
patch("hermes_cli.managed_uv.subprocess.run") as mock_run:
mock_run.return_value = MagicMock(returncode=1, stderr="nope")
from hermes_cli.managed_uv import update_managed_uv
result = update_managed_uv()
# Still returns the path — failure is non-fatal
assert result == str(tmp_path / "bin" / "uv")
# ---------------------------------------------------------------------------
# _install_uv internals
# ---------------------------------------------------------------------------
class TestInstallUvInternals:
def test_posix_sets_uv_unmanaged_install(self, tmp_path):
target = tmp_path / "bin" / "uv"
with patch("hermes_cli.managed_uv._install_uv_posix") as mock_posix:
from hermes_cli.managed_uv import _install_uv
_install_uv(target)
mock_posix.assert_called_once()
call_env = mock_posix.call_args[0][0]
assert call_env["UV_UNMANAGED_INSTALL"] == str(tmp_path / "bin")
def test_windows_sets_uv_install_dir(self, tmp_path):
target = tmp_path / "bin" / "uv.exe"
with patch("hermes_cli.managed_uv.platform.system", return_value="Windows"), \
patch("hermes_cli.managed_uv._install_uv_windows") as mock_windows:
from hermes_cli.managed_uv import _install_uv
_install_uv(target)
mock_windows.assert_called_once()
call_env = mock_windows.call_args[0][0]
assert call_env["UV_INSTALL_DIR"] == str(tmp_path / "bin")