hermes-agent/tests/hermes_cli/test_argparse_flag_propagation.py
briandevans 5ecc07986f fix(cli): preserve -t/-m/--provider/--tui/--dev before chat subcommand
`hermes -t web chat` silently dropped the toolset filter (and the same
hold true for `-m`, `--provider`, `--tui`, `--dev` placed before
`chat`). Reported in #28780 for `-t/--toolsets`; the others are sibling
failures with the same root cause.

Root cause: the chat subparser re-declared these flags with `default=None`
(or `default=False` for store_true) on top of the matching top-level
parser flags. When argparse dispatches into the subparser it shares the
namespace via `dest`, so the subparser's default overwrites whatever the
top-level parser parsed before the subcommand. `-s/--skills`, `-r/-c/-w`,
`--yolo`, and `--pass-session-id` already use `default=argparse.SUPPRESS`
for exactly this reason — the chat-subparser action becomes a no-op
unless the user explicitly passes the flag after `chat`, and the parent
value survives.

Reproduction (origin/main, before fix):

  >>> parser.parse_known_args(["-t", "web", "chat"]).toolsets
  None
  >>> parser.parse_known_args(["chat", "-t", "web"]).toolsets
  'web'

After fix:

  >>> parser.parse_known_args(["-t", "web", "chat"]).toolsets
  'web'
  >>> parser.parse_known_args(["chat", "-t", "web"]).toolsets
  'web'

Sibling flags fixed in the same commit because they share the exact same
argparse pattern bug — verified via a new contract test that scans every
chat-subparser action whose `dest` is also on the top-level parser and
asserts `default is argparse.SUPPRESS`. The test fails on origin/main
listing all five offenders and passes after this fix.

Test additions in tests/hermes_cli/test_argparse_flag_propagation.py:
- TestChatSubparserInheritedValueFlags exercising real `_parser` build
  (not the hand-rolled replica) so it catches future drift.
- Parametrized before-chat / after-chat cases for `-t`, `--toolsets`,
  `-m`, `--model`, `--provider`.
- Negative case: passing none of the flags leaves attrs at the top-level
  parser's `None` default (SUPPRESS does not remove existing attrs).
- Combined case: all three value flags before `chat` simultaneously.
- store_true cases for `--tui` / `--dev`.
- Contract test asserting every shared-`dest` flag on chat uses SUPPRESS.

Fixes #28780.
2026-07-11 03:51:43 -07:00

339 lines
14 KiB
Python

"""Tests for parent→subparser flag propagation.
When flags like --yolo, -w, -s exist on both the parent parser and the 'chat'
subparser, placing the flag BEFORE the subcommand (e.g. 'hermes --yolo chat')
must not silently drop the flag value.
Regression test for: argparse subparser default=False overwriting parent's
parsed True when the same argument is defined on both parsers.
Fix: chat subparser uses default=argparse.SUPPRESS for all duplicated flags,
so the subparser only sets the attribute when the user explicitly provides it.
"""
import argparse
import os
import sys
import pytest
def _build_parser():
"""Build the hermes argument parser from the real code.
We import the real main() and extract the parser it builds.
Since main() is a large function that does much more than parse args,
we replicate just the parser structure here to avoid side effects.
"""
parser = argparse.ArgumentParser(prog="hermes")
parser.add_argument("--resume", "-r", metavar="SESSION", default=None)
parser.add_argument(
"--continue", "-c", dest="continue_last", nargs="?",
const=True, default=None, metavar="SESSION_NAME",
)
parser.add_argument("--worktree", "-w", action="store_true", default=False)
parser.add_argument("--skills", "-s", action="append", default=None)
parser.add_argument("--yolo", action="store_true", default=False)
parser.add_argument("--pass-session-id", action="store_true", default=False)
subparsers = parser.add_subparsers(dest="command")
chat = subparsers.add_parser("chat")
# These MUST use argparse.SUPPRESS to avoid overwriting parent values
chat.add_argument("--yolo", action="store_true",
default=argparse.SUPPRESS)
chat.add_argument("--worktree", "-w", action="store_true",
default=argparse.SUPPRESS)
chat.add_argument("--skills", "-s", action="append",
default=argparse.SUPPRESS)
chat.add_argument("--pass-session-id", action="store_true",
default=argparse.SUPPRESS)
chat.add_argument("--resume", "-r", metavar="SESSION_ID",
default=argparse.SUPPRESS)
chat.add_argument(
"--continue", "-c", dest="continue_last", nargs="?",
const=True, default=argparse.SUPPRESS, metavar="SESSION_NAME",
)
return parser
class TestChatVerboseArg:
"""Verify chat --verbose preserves config fallback when absent."""
def test_chat_without_verbose_leaves_attribute_unset(self):
from hermes_cli._parser import build_top_level_parser
parser, _subparsers, _chat_parser = build_top_level_parser()
args = parser.parse_args(["chat"])
assert not hasattr(args, "verbose")
def test_chat_verbose_sets_attribute_true(self):
from hermes_cli._parser import build_top_level_parser
parser, _subparsers, _chat_parser = build_top_level_parser()
args = parser.parse_args(["chat", "--verbose"])
assert args.verbose is True
def test_cmd_chat_forwards_none_when_verbose_is_absent(self, monkeypatch):
import types
import sys
import hermes_cli.main as main_mod
from hermes_cli._parser import build_top_level_parser
parser, _subparsers, chat_parser = build_top_level_parser()
chat_parser.set_defaults(func=main_mod.cmd_chat)
args = parser.parse_args(["chat"])
captured = {}
fake_cli = types.ModuleType("cli")
def fake_main(**kwargs):
captured.update(kwargs)
setattr(fake_cli, "main", fake_main)
fake_banner = types.ModuleType("hermes_cli.banner")
setattr(fake_banner, "prefetch_update_check", lambda: None)
fake_skills_sync = types.ModuleType("tools.skills_sync")
setattr(fake_skills_sync, "sync_skills", lambda quiet=True: None)
monkeypatch.setitem(sys.modules, "cli", fake_cli)
monkeypatch.setitem(sys.modules, "hermes_cli.banner", fake_banner)
monkeypatch.setitem(sys.modules, "tools.skills_sync", fake_skills_sync)
monkeypatch.setattr(main_mod, "_has_any_provider_configured", lambda: True)
monkeypatch.setattr(main_mod, "_pin_kanban_board_env", lambda: None)
main_mod.cmd_chat(args)
assert captured["quiet"] is False
assert "verbose" not in captured
class TestYoloEnvVar:
"""Verify --yolo sets HERMES_YOLO_MODE regardless of flag position.
This tests the actual cmd_chat logic pattern (getattr → os.environ).
"""
@pytest.fixture(autouse=True)
def _clean_env(self):
os.environ.pop("HERMES_YOLO_MODE", None)
yield
os.environ.pop("HERMES_YOLO_MODE", None)
def _simulate_cmd_chat_yolo_check(self, args):
"""Replicate the exact check from cmd_chat in main.py."""
if getattr(args, "yolo", False):
os.environ["HERMES_YOLO_MODE"] = "1"
def test_yolo_before_chat_sets_env(self):
parser = _build_parser()
args = parser.parse_args(["--yolo", "chat"])
self._simulate_cmd_chat_yolo_check(args)
assert os.environ.get("HERMES_YOLO_MODE") == "1"
def test_yolo_after_chat_sets_env(self):
parser = _build_parser()
args = parser.parse_args(["chat", "--yolo"])
self._simulate_cmd_chat_yolo_check(args)
assert os.environ.get("HERMES_YOLO_MODE") == "1"
def test_no_yolo_no_env(self):
parser = _build_parser()
args = parser.parse_args(["chat"])
self._simulate_cmd_chat_yolo_check(args)
assert os.environ.get("HERMES_YOLO_MODE") is None
class TestAcceptHooksOnAgentSubparsers:
"""Verify --accept-hooks is accepted at every agent-subcommand
position (before the subcommand, between group/subcommand, and
after the leaf subcommand) for gateway/cron/mcp/acp. Regression
against prior behaviour where the flag only worked on the root
parser and `chat`, so `hermes gateway run --accept-hooks` failed
with `unrecognized arguments`."""
ARGVS = [
["--accept-hooks", "gateway", "run", "--help"],
["gateway", "--accept-hooks", "run", "--help"],
["gateway", "run", "--accept-hooks", "--help"],
["--accept-hooks", "cron", "tick", "--help"],
["cron", "--accept-hooks", "tick", "--help"],
["cron", "tick", "--accept-hooks", "--help"],
["cron", "run", "--accept-hooks", "dummy-id", "--help"],
["--accept-hooks", "mcp", "serve", "--help"],
["mcp", "--accept-hooks", "serve", "--help"],
["mcp", "serve", "--accept-hooks", "--help"],
["acp", "--accept-hooks", "--help"],
]
# One driver subprocess parses ALL argvs: hermes_cli.main is a very heavy
# import (previously 11 separate `python -m hermes_cli.main` spawns with a
# 15s timeout each — a cold import on a loaded CI worker regularly blew
# that deadline, making this test flaky). Importing once and parsing 11
# times removes the repeated-import cost entirely; the generous timeout
# only trips on a genuine hang. `--help` exits via SystemExit(0), which
# the driver catches per argv.
_DRIVER = r"""
import io, json, sys
from contextlib import redirect_stdout, redirect_stderr
import hermes_cli.main as main_mod
argvs = json.loads(sys.argv[1])
results = []
for argv in argvs:
sys.argv = ["hermes", *argv]
out, err = io.StringIO(), io.StringIO()
code = 0
try:
with redirect_stdout(out), redirect_stderr(err):
main_mod.main()
except SystemExit as exc:
code = int(exc.code or 0)
except Exception as exc: # noqa: BLE001 - report, don't crash the driver
code = -1
err.write(repr(exc))
results.append({"argv": argv, "code": code, "stderr": err.getvalue()[:300]})
print(json.dumps(results))
"""
def test_accepted_at_every_position(self):
"""Every `hermes <argv>` must exit 0 (help) rather than failing
with `unrecognized arguments`."""
import json
import subprocess
result = subprocess.run(
[sys.executable, "-c", self._DRIVER, json.dumps(self.ARGVS)],
capture_output=True,
text=True,
timeout=180,
)
assert result.returncode == 0, (
f"driver failed rc={result.returncode}\n"
f"stdout: {result.stdout[:500]}\nstderr: {result.stderr[:500]}"
)
for entry in json.loads(result.stdout.strip().splitlines()[-1]):
assert entry["code"] == 0, (
f"argv={entry['argv']!r} returned {entry['code']}\n"
f"stderr: {entry['stderr']}"
)
assert "unrecognized arguments" not in entry["stderr"]
class TestChatSubparserInheritedValueFlags:
"""Verify -t/--toolsets, -m/--model and --provider survive parent→chat
subparser dispatch.
Regression test for #28780: `hermes -t web chat` silently dropped the
toolset because the chat subparser re-declared `-t/--toolsets` with
`default=None`, which clobbered the top-level parser's value during
subparser dispatch.
Uses the real `hermes_cli._parser.build_top_level_parser()` rather than
the hand-rolled replica above so this also fails if the production
parser drifts back to `default=None` on these flags.
"""
@pytest.fixture
def real_parser(self):
from hermes_cli._parser import build_top_level_parser
parser, _subparsers, _chat = build_top_level_parser()
return parser
@pytest.mark.parametrize("flag,attr,value", [
("-t", "toolsets", "web"),
("--toolsets", "toolsets", "web,terminal"),
("-m", "model", "anthropic/claude-sonnet-4"),
("--model", "model", "openai/gpt-4"),
("--provider", "provider", "openrouter"),
])
def test_flag_before_chat_is_preserved(self, real_parser, flag, attr, value):
args, _ = real_parser.parse_known_args([flag, value, "chat"])
assert getattr(args, attr, None) == value, (
f"`hermes {flag} {value} chat` lost the flag — got "
f"{getattr(args, attr, None)!r}, expected {value!r}"
)
@pytest.mark.parametrize("flag,attr,value", [
("-t", "toolsets", "web"),
("--toolsets", "toolsets", "web,terminal"),
("-m", "model", "anthropic/claude-sonnet-4"),
("--model", "model", "openai/gpt-4"),
("--provider", "provider", "openrouter"),
])
def test_flag_after_chat_still_works(self, real_parser, flag, attr, value):
args, _ = real_parser.parse_known_args(["chat", flag, value])
assert getattr(args, attr, None) == value
def test_no_flag_leaves_attrs_at_top_level_default(self, real_parser):
"""When the user passes none of the inherited flags, the top-level
parser's `default=None` still seeds the namespace — the SUPPRESS on
the subparser must not remove existing attributes."""
args, _ = real_parser.parse_known_args(["chat"])
assert getattr(args, "toolsets", "MISSING") is None
assert getattr(args, "model", "MISSING") is None
assert getattr(args, "provider", "MISSING") is None
def test_all_three_flags_before_chat(self, real_parser):
"""Issue #28780 reporter's case generalized: passing every inherited
value flag before `chat` must preserve all of them simultaneously."""
args, _ = real_parser.parse_known_args([
"-t", "web",
"-m", "anthropic/claude-sonnet-4",
"--provider", "openrouter",
"chat",
])
assert args.toolsets == "web"
assert args.model == "anthropic/claude-sonnet-4"
assert args.provider == "openrouter"
@pytest.mark.parametrize("flag,attr", [
("--tui", "tui"),
("--cli", "cli"),
("--dev", "tui_dev"),
])
def test_store_true_flag_before_chat_is_preserved(
self, real_parser, flag, attr,
):
"""`--tui` / `--cli` / `--dev` are store_true flags inherited by chat; the same
SUPPRESS contract applies. Without it, the subparser's `default=False`
would clobber the parent's `True` when used as `hermes --tui chat`."""
args, _ = real_parser.parse_known_args([flag, "chat"])
assert getattr(args, attr, None) is True, (
f"`hermes {flag} chat` lost the flag — got "
f"{getattr(args, attr, None)!r}, expected True"
)
def test_chat_subparser_inherited_value_flags_use_suppress(self):
"""Contract test for the underlying invariant.
Any chat-subparser flag whose `dest` also exists on the top-level
parser MUST declare `default=argparse.SUPPRESS`, otherwise the
subparser silently overwrites the top-level value with its own
default during dispatch. This is the structural class behind #28780.
"""
from hermes_cli._parser import build_top_level_parser
parser, _subparsers, chat_parser = build_top_level_parser()
top_level_dests = {
a.dest for a in parser._actions
if a.option_strings and a.dest != "help"
}
offenders = []
for action in chat_parser._actions:
if not action.option_strings or action.dest == "help":
continue
if action.dest not in top_level_dests:
continue
if action.default is not argparse.SUPPRESS:
offenders.append((action.option_strings, action.dest, action.default))
assert not offenders, (
"Chat subparser redeclares these top-level flags without "
"default=argparse.SUPPRESS; they will silently clobber the "
"top-level value when used as `hermes <flag> <value> chat`:\n "
+ "\n ".join(f"{opts} dest={dest} default={d!r}"
for opts, dest, d in offenders)
)