"""Tests that src/api_hooks.py has NO top-level heavy imports (websockets, cost_tracker, session_logger). Per the Main Thread Purity Invariant, the 3 heavy modules are loaded lazily via _require_warmed() at use sites. The file already has 'from __future__ import annotations' so type hints are strings. These tests run in a fresh subprocess to ensure no warmup state leaks. """ import subprocess import sys import textwrap from pathlib import Path ROOT = Path(__file__).resolve().parent.parent def _run_in_subprocess(snippet: str) -> subprocess.CompletedProcess: script = textwrap.dedent(snippet) return subprocess.run( [sys.executable, "-c", script], capture_output=True, text=True, cwd=str(ROOT), timeout=30, ) def test_api_hooks_does_not_import_heavy_at_module_level() -> None: res = _run_in_subprocess(""" import sys import src.api_hooks for mod in ('websockets', 'src.cost_tracker', 'src.session_logger'): print(mod, mod in sys.modules) """) assert res.returncode == 0, f"stderr: {res.stderr}" for line in res.stdout.strip().splitlines(): name, present = line.split() assert present == "False", f"src.api_hooks triggered {name} import: {res.stdout}" def test_api_hooks_loads_heavy_module_only_on_require_warmed() -> None: res = _run_in_subprocess(""" import sys import src.api_hooks pre = ('websockets' in sys.modules, 'src.cost_tracker' in sys.modules, 'src.session_logger' in sys.modules) print('PRE', pre) _require_warmed = src.api_hooks._require_warmed ct = _require_warmed('src.cost_tracker') post1 = ('src.cost_tracker' in sys.modules, ct is _require_warmed('src.cost_tracker')) print('POST1', post1) """) assert res.returncode == 0, f"stderr: {res.stderr}" lines = res.stdout.strip().splitlines() assert "PRE (False, False, False)" in lines[0], f"heavy modules leaked at import: {res.stdout}" assert "POST1 (True, True)" in lines[1], f"_require_warmed did not load/cache src.cost_tracker: {res.stdout}" def test_audit_sees_no_violation_in_api_hooks() -> None: res = _run_in_subprocess(""" import ast from pathlib import Path tree = ast.parse(Path('src/api_hooks.py').read_text(encoding='utf-8')) heavy = {'websockets', 'src.cost_tracker', 'src.session_logger'} for node in tree.body: if isinstance(node, ast.Import): for alias in node.names: top = alias.name.split('.')[0] if top in heavy or any(alias.name.startswith(h + '.') for h in heavy): print('VIOLATION:', alias.name) elif isinstance(node, ast.ImportFrom): if node.module and (node.module in heavy or any(node.module.startswith(h + '.') for h in heavy)): print('VIOLATION:', node.module) print('OK') """) assert res.returncode == 0, f"stderr: {res.stderr}" assert "VIOLATION" not in res.stdout assert "OK" in res.stdout