Two assertions per offloaded site:
- a loop probe, where the stubbed callee records whether an event loop is
running in its own thread — the idiom already used by
tests/hermes_cli/test_cron_dashboard_off_loop.py; and
- a concurrency proof, where the stubbed callee blocks on a threading.Event
while an unrelated request is timed. On the unfixed handlers that request
waits out the whole block; served off the loop it returns in
milliseconds.
The concurrency proof needs a single event loop across requests, so the
client fixture enters the TestClient context manager: that pins one
blocking portal for the whole fixture, where a bare TestClient(app) would
spin up a fresh loop per request and pass even unfixed.
Also covers the status-code mapping through the executor hop (404 on a
missing profile, 400 on a rename collision, 404 from the resolve that stays
on the loop ahead of describe-auto) and the _MISSING sentinel cases: a
desktop.json holding `null` still reports exists=true, an absent one
reports exists=false, and an empty SOUL.md is still distinguishable from a
missing one.
The client fixtures read web_server._SESSION_TOKEN from the module rather
than pinning a literal. web_server resolves that token once at import, so
whichever test file imports it first fixes the value for the session and a
later monkeypatch.setenv is silently ignored — two files hardcoding
different tokens would 401 depending on collection order.
Both files were routed through the shared atomic writers earlier in this
branch. tempfile.mkstemp creates the temp file 0600 and the atomic swap
carries that mode onto the target, so the *create* paths silently tightened
two files that previously landed at the umask default:
- web_routers/profiles.py: the dashboard persona editor's first-ever Save has
no prior SOUL.md to copy permissions from, so the existing guard skipped the
chmod entirely -- contradicting the comment directly below it, which states
profile SOUL.md is created 0644 and is not run through _secure_file.
- profile_distribution.py: atomic_yaml_write only restores a mode it captured
from a file that already existed. _materialize() calls write_manifest() with
no manifest on disk whenever a distribution declares an explicit
distribution_owned allowlist that omits distribution.yaml, so the staged
copy is never placed in the profile.
Both are fixed with a local chmod at the two sites this branch regressed;
utils.py's public mode semantics are left alone. profiles.py now also
distinguishes "no file yet" (FileNotFoundError -> 0644) from "stat failed for
some other reason" (-> leave the mode alone rather than guess at it).
uninstall.py and xai_retirement.py have no create path and are unchanged: the
former captures prior_mode unconditionally after a successful read_text(), and
the latter runs require_readable_config_before_write() first.
The four new mode-preservation guards assert POSIX permission bits, which
Windows does not model (os.chmod only toggles the read-only flag there).
Guard them the way the suite already guards POSIX-specific semantics so the
tests stay meaningful on Linux/macOS without failing for Windows contributors.
The symlink cases stay unguarded, matching the existing symlink tests in
tests/hermes_cli/.
`utils.atomic_write_text`'s docstring states the invariant: it exists "so that
every destructive file rewrite in the codebase shares one implementation."
Four full-file rewrites of *existing user-authored files* still bypass it and
use a bare truncating `open(path, "w")` / `Path.write_text()`, which truncates
the target before the new content is produced. A crash, SIGINT, or ENOSPC
mid-write therefore leaves the file empty or half-written.
In all four cases the read half degrades silently to a default rather than
erroring, so the damage is invisible and the next write cements it:
* `xai_retirement.apply_migration()` rewrites the user's config.yaml. Merged
commit beaa1a08e added a readability guard here and noted the writer "lives
outside the atomic_yaml_write path, so the chokepoint didn't cover it"; this
closes the durability half it left open. `--no-backup` is a documented flag,
so on that path the truncated file is the only copy that exists, and the
loader returns early on `doc is None` — the next run reports nothing to
migrate rather than surfacing the damage.
* `uninstall.remove_path_from_shell_configs()` rewrites the user's shell rc
(~/.bashrc, ~/.zshrc, ...). Hermes does not own these files and this function
takes no backup; the enclosing `except Exception` downgrades a partial write
to a warning, so the next login just starts a bare shell.
* `web_routers.profiles.update_profile_soul()` replaces SOUL.md from the
dashboard editor. The paired GET reports an unreadable file as
`{"content": "", "exists": False}`, so an interrupted save presents as "your
persona was never set" and the editor's next Save persists the empty document.
* `profile_distribution.write_manifest()` rewrites distribution.yaml on every
install/update. `read_manifest` treats an unparseable manifest as "not a
distribution", silently dropping update tracking and env_requires.
The xAI migration keeps its ruamel round-trip dumper (comments, key order and
quoting must survive) and now serializes to a string before handing the bytes
to the shared writer. `write_manifest` moves to `atomic_yaml_write`, whose
SafeDumper output the manifest already round-trips through, retiring the local
`_dump_yaml` helper.
`atomic_write_text` recreates the target from a 0600 temp file, so each of its
call sites re-applies the file's previous permission bits: `_secure_file`
deliberately leaves config.yaml alone under managed (NixOS 0640) and container
installs, shell rc files are normally 0644, and profile SOUL.md is created 0644
and never secured. `atomic_yaml_write` already preserves mode and owner itself.
Routing through `atomic_replace` also keeps a symlinked config.yaml or ~/.zshrc
(dotfiles repo, managed deployment) pointing at the real file.
Tests: one regression test per site fails on clean main (the interrupted write
completes there and destroys the file) and passes here; the remaining cases are
behaviour guards covering symlink survival, permission preservation, comment
round-tripping, and the existing happy paths.
briandevans