import subprocess
from pathlib import Path
import anyio
from titan_factory import mcp_code_server
def _git(repo: Path, *args: str) -> None:
subprocess.run(
["git", *args],
cwd=repo,
check=True,
stdout=subprocess.DEVNULL,
stderr=subprocess.DEVNULL,
)
def test_candidate_failure_writes_error_and_traceback_files(tmp_path: Path, monkeypatch) -> None:
repo = tmp_path / "repo"
repo.mkdir()
(repo / "hello.txt").write_text("hello\n", encoding="utf-8")
_git(repo, "init")
_git(repo, "add", "hello.txt")
subprocess.run(
["git", "-c", "user.email=test@example.com", "-c", "user.name=test", "commit", "-m", "init"],
cwd=repo,
check=True,
stdout=subprocess.DEVNULL,
stderr=subprocess.DEVNULL,
)
out_dir = tmp_path / "out"
out_dir.mkdir(parents=True, exist_ok=True)
monkeypatch.setenv("TITAN_MCP_OUT_DIR", str(out_dir))
async def fake_call_llm_json(
*,
provider_name: str,
model: str,
system_prompt: str,
user_prompt: str,
temperature: float,
max_tokens: int,
):
_ = (provider_name, model, system_prompt, user_prompt, temperature, max_tokens)
raise RuntimeError("boom")
monkeypatch.setattr(mcp_code_server, "_call_llm_json", fake_call_llm_json)
async def run():
return await mcp_code_server.titan_code_solve(
repo_path=str(repo),
goal="This should fail",
planning_mode="off",
auto_context_mode="off",
max_candidates=1,
candidate_concurrency=1,
max_fix_rounds=0,
vision_mode="auto",
section_creativity_mode="off",
apply_to_repo=False,
allow_nonpassing_winner=True, # still returns best effort candidate
)
result = anyio.run(run)
assert result["run_dir"]
assert result["candidates"]
cand0 = result["candidates"][0]
assert cand0["ok"] is False
assert "boom" in (cand0["error"] or "")
cand_dir = Path(cand0["candidate_dir"])
assert (cand_dir / "error.txt").exists()
assert "boom" in (cand_dir / "error.txt").read_text(encoding="utf-8", errors="replace")
assert (cand_dir / "traceback.txt").exists()
assert (cand_dir / "candidate_summary.json").exists()
run_dir = Path(result["run_dir"])
assert (run_dir / "run_summary.json").exists()
