Files
gstack/test/timeline-stop-hook.test.ts
T
Garry TanandClaude Fable 5 45b72989e6 fix(hooks): timeline Stop hook reads a 256KB tail instead of the whole file
The Stop hook runs on EVERY Claude Code turn machine-wide and re-read +
JSON-parsed the entire timeline each time, scaling to the 10MB size cap
(~100-300ms per turn of pure overhead). It now reads only the last 256KB
via fstat + positioned read, discarding the first partial line when the
window starts mid-file.

Semantics: a dangling "started" older than the last 256KB of appends
belongs to a session long gone — beyond repair interest. The window can
never fabricate a dangling entry ("completed" is always appended AFTER its
"started", so any started inside the window has its completion inside the
window too), so idempotency holds. The fail-open contract is unchanged:
exit 0 always, size cap kept, deadline re-checked before the write.

New test: a >256KB timeline where a recent dangling entry still gets
repaired while an old out-of-window dangler is left alone; all existing
fail-open cases pass unchanged.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
2026-08-16 14:13:15 -07:00

229 lines
8.2 KiB
TypeScript

/**
* Timeline Stop hook (#2553) — fail-open contract (F5).
*
* The preamble writes event:"started" at every skill start; the completion
* write is end-of-workflow prose and unenforceable, so interrupted sessions
* leaked started > completed forever. The Stop hook closes dangling entries.
*
* Contract under test: ALWAYS exits 0 (corrupt timeline, missing timeline,
* garbage stdin), append-only, and the normal path appends event:"completed"
* with outcome "unknown" + source "stop-hook" for every un-closed "started".
*/
import { describe, test, expect, beforeEach, afterEach } from 'bun:test';
import { spawnSync } from 'child_process';
import * as fs from 'fs';
import * as os from 'os';
import * as path from 'path';
const ROOT = path.resolve(import.meta.dir, '..');
const HOOK = path.join(ROOT, 'hosts', 'claude', 'hooks', 'timeline-stop-hook');
const SLUG = 'stop-hook-test-project';
let tmpHome: string;
let projectDir: string;
let timelinePath: string;
beforeEach(() => {
tmpHome = fs.mkdtempSync(path.join(os.tmpdir(), 'gstack-stop-hook-home-'));
projectDir = fs.mkdtempSync(path.join(os.tmpdir(), 'gstack-stop-hook-proj-'));
fs.mkdirSync(path.join(tmpHome, 'projects', SLUG), { recursive: true });
timelinePath = path.join(tmpHome, 'projects', SLUG, 'timeline.jsonl');
});
afterEach(() => {
fs.rmSync(tmpHome, { recursive: true, force: true });
fs.rmSync(projectDir, { recursive: true, force: true });
});
function runHook(stdin: string): { exitCode: number; stdout: string; stderr: string } {
const r = spawnSync('bash', [HOOK], {
input: stdin,
encoding: 'utf-8',
env: {
...process.env,
GSTACK_HOME: tmpHome,
GSTACK_PROJECT_SLUG: SLUG, // deterministic slug, no git required
},
timeout: 15_000,
});
return { exitCode: r.status ?? 1, stdout: r.stdout, stderr: r.stderr };
}
function stopPayload(): string {
return JSON.stringify({
session_id: 'sess-abc',
hook_event_name: 'Stop',
cwd: projectDir,
});
}
function timelineEntries(): any[] {
if (!fs.existsSync(timelinePath)) return [];
return fs
.readFileSync(timelinePath, 'utf-8')
.split('\n')
.filter((l) => l.trim())
.map((l) => {
try {
return JSON.parse(l);
} catch {
return { __corrupt: l };
}
});
}
describe('timeline-stop-hook (#2553, F5 fail-open)', () => {
test('normal path: closes dangling started entries, leaves closed pairs alone', () => {
fs.writeFileSync(
timelinePath,
[
JSON.stringify({ skill: 'review', event: 'started', branch: 'main', session: '11-1' }),
JSON.stringify({ skill: 'ship', event: 'started', session: '22-2' }),
JSON.stringify({ skill: 'ship', event: 'completed', session: '22-2', outcome: 'success' }),
].join('\n') + '\n',
);
const r = runHook(stopPayload());
expect(r.exitCode).toBe(0);
const entries = timelineEntries();
// Append-only: the three originals survive verbatim in order.
expect(entries[0]).toMatchObject({ skill: 'review', event: 'started' });
expect(entries[2]).toMatchObject({ skill: 'ship', event: 'completed', outcome: 'success' });
const repairs = entries.filter((e) => e.source === 'stop-hook');
expect(repairs).toHaveLength(1);
expect(repairs[0]).toMatchObject({
skill: 'review',
event: 'completed',
outcome: 'unknown',
branch: 'main',
session: '11-1',
});
expect(typeof repairs[0].ts).toBe('string');
});
test('idempotent: a second Stop appends nothing new', () => {
fs.writeFileSync(
timelinePath,
JSON.stringify({ skill: 'qa', event: 'started', session: '33-3' }) + '\n',
);
expect(runHook(stopPayload()).exitCode).toBe(0);
const afterFirst = timelineEntries().length;
expect(runHook(stopPayload()).exitCode).toBe(0);
expect(timelineEntries().length).toBe(afterFirst);
});
test('exit 0 on missing timeline (nothing written, nothing created)', () => {
const r = runHook(stopPayload());
expect(r.exitCode).toBe(0);
expect(fs.existsSync(timelinePath)).toBe(false);
});
test('exit 0 on a corrupt timeline; corrupt lines are skipped, valid ones still repaired', () => {
fs.writeFileSync(
timelinePath,
[
'this is not json at all {{{',
JSON.stringify({ skill: 'qa', event: 'started', session: '44-4' }),
'{"half": "an object"',
].join('\n') + '\n',
);
const r = runHook(stopPayload());
expect(r.exitCode).toBe(0);
const repairs = timelineEntries().filter((e) => e.source === 'stop-hook');
expect(repairs).toHaveLength(1);
expect(repairs[0].skill).toBe('qa');
});
test('exit 0 on a FULLY corrupt timeline (no valid entries → no write)', () => {
const garbage = 'garbage\n{{{\n';
fs.writeFileSync(timelinePath, garbage);
const r = runHook(stopPayload());
expect(r.exitCode).toBe(0);
expect(fs.readFileSync(timelinePath, 'utf-8')).toBe(garbage);
});
test('exit 0 on garbage stdin', () => {
fs.writeFileSync(
timelinePath,
JSON.stringify({ skill: 'qa', event: 'started', session: '55-5' }) + '\n',
);
const r = runHook('not json');
expect(r.exitCode).toBe(0);
});
test('exit 0 on empty stdin', () => {
expect(runHook('').exitCode).toBe(0);
});
test('tail window (P3): a recent dangling entry in a >256KB timeline is still repaired', () => {
const lines: string[] = [];
// An old dangling entry that falls OUTSIDE the 256KB tail window —
// beyond repair interest by design (its session is long gone).
lines.push(JSON.stringify({ skill: 'review', event: 'started', session: 'old-1' }));
// >512KB of closed pairs pushes the old entry well past the window while
// proving windowed parsing still walks real entries.
let n = 0;
while (lines.length * 100 < 512 * 1024) {
lines.push(
JSON.stringify({ skill: 'qa', event: 'started', session: `pad-${n}`, pad: '#'.repeat(40) }),
);
lines.push(JSON.stringify({ skill: 'qa', event: 'completed', session: `pad-${n}`, outcome: 'success' }));
n++;
}
lines.push(JSON.stringify({ skill: 'ship', event: 'started', session: 'recent-9' }));
fs.writeFileSync(timelinePath, lines.join('\n') + '\n');
expect(fs.statSync(timelinePath).size).toBeGreaterThan(256 * 1024);
const r = runHook(stopPayload());
expect(r.exitCode).toBe(0);
const repairs = timelineEntries().filter((e) => e.source === 'stop-hook');
expect(repairs).toHaveLength(1);
expect(repairs[0]).toMatchObject({
skill: 'ship',
event: 'completed',
outcome: 'unknown',
session: 'recent-9',
});
});
test('oversized timeline is skipped, untouched, and still exits 0 (fail-open size cap)', () => {
const line = JSON.stringify({ skill: 'qa', event: 'started', session: '66-6' }) + '\n';
const filler = '#'.repeat(1024 * 1024);
fs.writeFileSync(timelinePath, line + filler.repeat(11));
const sizeBefore = fs.statSync(timelinePath).size;
const r = runHook(stopPayload());
expect(r.exitCode).toBe(0);
expect(fs.statSync(timelinePath).size).toBe(sizeBefore);
});
});
describe('timeline-stop-hook wiring', () => {
test('setup registers the Stop hook with its own source tag and tears it down on --no-team', () => {
const setup = fs.readFileSync(path.join(ROOT, 'setup'), 'utf-8');
expect(setup).toContain('--event Stop');
expect(setup).toContain('--source gstack-timeline-stop');
expect(setup).toContain('hosts/claude/hooks/timeline-stop-hook');
// --no-team teardown removes it alongside the plan-tune hooks.
const teardown = setup.slice(setup.indexOf('# Also tear down plan-tune'));
expect(teardown).toContain('remove-source --source gstack-timeline-stop');
});
test('gstack-uninstall removes the Stop hook registration', () => {
const uninstall = fs.readFileSync(path.join(ROOT, 'bin', 'gstack-uninstall'), 'utf-8');
expect(uninstall).toContain('remove-source --source gstack-timeline-stop');
});
test('the bash shim is fail-open: exits 0 even when bun is unavailable', () => {
const r = spawnSync('bash', [HOOK], {
input: '{}',
encoding: 'utf-8',
env: { HOME: tmpHome, PATH: '/usr/bin:/bin', GSTACK_HOME: tmpHome },
timeout: 15_000,
});
expect(r.status).toBe(0);
});
});