feat: add git-consistent memory gateway architecture

gateway/tests/conftest.py

@@ -0,0 +1,135 @@
+from __future__ import annotations
+
+from dataclasses import dataclass
+import os
+from pathlib import Path
+import subprocess
+from typing import Any
+
+import pytest
+from fastapi.testclient import TestClient
+
+# Keep module-level app import from trying to write to /data on local tests.
+os.environ.setdefault("WORKSPACES_ROOT", "/tmp/qmd-gateway-tests/workspaces")
+os.environ.setdefault("WORKSPACE_STATE_DIR", "/tmp/qmd-gateway-tests/state")
+os.environ.setdefault("GIT_MIRROR_PATH", "/tmp/qmd-gateway-tests/git-mirror/repo.git")
+os.environ.setdefault("GIT_REMOTE_URL", "/tmp/qmd-gateway-tests/remote.git")
+
+from app.config import Settings
+from app.main import create_app
+from app.models import QueryType
+
+
+class FakeQMDClient:
+    def __init__(self) -> None:
+        self.collections: dict[str, dict[str, Path]] = {}
+        self.update_calls: list[str] = []
+        self.embed_calls: list[str] = []
+
+    def ensure_collection(self, index_name: str, collection_name: str, workspace_path: Path) -> bool:
+        bucket = self.collections.setdefault(index_name, {})
+        if collection_name in bucket:
+            return False
+        bucket[collection_name] = workspace_path
+        return True
+
+    def list_collections(self, index_name: str) -> set[str]:
+        return set(self.collections.get(index_name, {}).keys())
+
+    def update_workspace(self, index_name: str) -> None:
+        self.update_calls.append(index_name)
+
+    def embed_workspace_if_needed(self, index_name: str, should_embed: bool) -> bool:
+        if should_embed:
+            self.embed_calls.append(index_name)
+            return True
+        return False
+
+    def run_query(self, *, index_name: str, collection_name: str, query_type: QueryType, query: str, n: int):
+        workspace = self.collections[index_name][collection_name]
+        needle = query.lower()
+        matches: list[dict[str, Any]] = []
+        for path in sorted(workspace.rglob("*.md")):
+            text = path.read_text(encoding="utf-8")
+            if needle in text.lower() or needle in path.name.lower():
+                matches.append({"file": str(path), "snippet": text[:120]})
+        return matches[:n], query_type.value
+
+
+@dataclass
+class TestRepo:
+    remote_path: Path
+    seed_path: Path
+
+    def commit_on_branch(self, branch: str, rel_path: str, content: str, message: str) -> str:
+        _run(["git", "-C", str(self.seed_path), "checkout", branch])
+        file_path = self.seed_path / rel_path
+        file_path.parent.mkdir(parents=True, exist_ok=True)
+        file_path.write_text(content, encoding="utf-8")
+        _run(["git", "-C", str(self.seed_path), "add", rel_path])
+        _run(["git", "-C", str(self.seed_path), "commit", "-m", message])
+        _run(["git", "-C", str(self.seed_path), "push", "origin", branch])
+        commit = _run(["git", "-C", str(self.seed_path), "rev-parse", "HEAD"]).strip()
+        return commit
+
+
+@pytest.fixture()
+def repo(tmp_path: Path) -> TestRepo:
+    remote = tmp_path / "remote.git"
+    seed = tmp_path / "seed"
+
+    _run(["git", "init", "--bare", str(remote)])
+    _run(["git", "clone", str(remote), str(seed)])
+    _run(["git", "-C", str(seed), "config", "user.name", "Test User"])
+    _run(["git", "-C", str(seed), "config", "user.email", "test@example.com"])
+
+    (seed / "README.md").write_text("main branch memory root\n", encoding="utf-8")
+    (seed / "docs" / "main-only.md").parent.mkdir(parents=True, exist_ok=True)
+    (seed / "docs" / "main-only.md").write_text("alpha-main-signal\n", encoding="utf-8")
+    _run(["git", "-C", str(seed), "add", "README.md", "docs/main-only.md"])
+    _run(["git", "-C", str(seed), "commit", "-m", "init main"])
+    _run(["git", "-C", str(seed), "branch", "-M", "main"])
+    _run(["git", "-C", str(seed), "push", "-u", "origin", "main"])
+
+    _run(["git", "-C", str(seed), "checkout", "-b", "memory/2026-03"])
+    (seed / "docs" / "monthly-only.md").write_text(
+        "beta-monthly-signal\nmonthly-exclusive-signal\n",
+        encoding="utf-8",
+    )
+    _run(["git", "-C", str(seed), "add", "docs/monthly-only.md"])
+    _run(["git", "-C", str(seed), "commit", "-m", "add monthly"])
+    _run(["git", "-C", str(seed), "push", "-u", "origin", "memory/2026-03"])
+
+    _run(["git", "-C", str(seed), "checkout", "main"])
+    (seed / "docs" / "main-exclusive.md").write_text("main-exclusive-signal\n", encoding="utf-8")
+    _run(["git", "-C", str(seed), "add", "docs/main-exclusive.md"])
+    _run(["git", "-C", str(seed), "commit", "-m", "add main exclusive"])
+    _run(["git", "-C", str(seed), "push", "origin", "main"])
+
+    return TestRepo(remote_path=remote, seed_path=seed)
+
+
+@pytest.fixture()
+def fake_qmd() -> FakeQMDClient:
+    return FakeQMDClient()
+
+
+@pytest.fixture()
+def client(tmp_path: Path, repo: TestRepo, fake_qmd: FakeQMDClient) -> TestClient:
+    settings = Settings(
+        git_remote_url=str(repo.remote_path),
+        git_mirror_path=tmp_path / "git-mirror" / "repo.git",
+        workspaces_root=tmp_path / "workspaces",
+        workspace_state_dir=tmp_path / "state",
+        xdg_cache_home=tmp_path / "cache",
+        xdg_config_home=tmp_path / "config",
+    )
+    app = create_app(settings=settings, qmd_client=fake_qmd)
+    return TestClient(app)
+
+
+def _run(args: list[str]) -> str:
+    proc = subprocess.run(args, check=False, capture_output=True, text=True)
+    if proc.returncode != 0:
+        raise RuntimeError(f"command failed: {' '.join(args)}\nstdout={proc.stdout}\nstderr={proc.stderr}")
+    return proc.stdout