chore(qa): harnesses clean up their temp folders

qa/audit.mjs

@@ -5,12 +5,13 @@ import { mkdtempSync, writeFileSync, mkdirSync } from 'node:fs';
 import { tmpdir } from 'node:os';
 import { dirname, join } from 'node:path';
 import { fileURLToPath } from 'node:url';
+import { sandboxDir } from './sandbox.mjs';
 
 const root = dirname(dirname(fileURLToPath(import.meta.url)));
 const out = join(root, 'qa', 'shots');
 mkdirSync(out, { recursive: true });
 
-const userData = mkdtempSync(join(tmpdir(), 'devdeck-qa-'));
+const userData = sandboxDir('devdeck-qa-');
 const app = await electron.launch({
   args: ['.', `--user-data-dir=${userData}`, '--no-sandbox', '--disable-gpu'],
   cwd: root,

qa/claude-update.mjs

@@ -8,14 +8,15 @@ import { execFileSync } from 'node:child_process';
 import { tmpdir } from 'node:os';
 import { dirname, join, resolve } from 'node:path';
 import { fileURLToPath } from 'node:url';
+import { sandboxDir } from './sandbox.mjs';
 
 // Windows harness (fixture claude.cmd on PATH). Run with npm run qa:update.
 const root = resolve(process.argv[2] ?? dirname(dirname(fileURLToPath(import.meta.url))));
 const shots = resolve(process.argv[3] ?? join(root, 'qa', 'shots', 'claude-update'));
 mkdirSync(shots, { recursive: true });
 const { closeElectron } = await import('file:///' + join(root, 'qa', 'electron-lifecycle.mjs').replace(/\\/g, '/'));
 
-const sandbox = mkdtempSync(join(tmpdir(), 'devdeck-update-'));
+const sandbox = sandboxDir('devdeck-update-');
 const repo = join(sandbox, 'update-workspace');
 const bin = join(sandbox, 'bin');
 const profile = join(sandbox, 'profile');

qa/close.mjs

@@ -17,20 +17,21 @@ import { tmpdir } from 'node:os';
 import { dirname, join } from 'node:path';
 import { fileURLToPath } from 'node:url';
 import { closeElectron } from './electron-lifecycle.mjs';
+import { sandboxDir } from './sandbox.mjs';
 
 const repo = dirname(dirname(fileURLToPath(import.meta.url)));
 const sleep = (ms) => new Promise((r) => setTimeout(r, ms));
 const stamp = () => new Date().toISOString().slice(11, 19);
 
-const fixtureRepo = mkdtempSync(join(tmpdir(), 'devdeck-close-fixture-'));
+const fixtureRepo = sandboxDir('devdeck-close-fixture-');
 writeFileSync(join(fixtureRepo, 'README.md'), '# fixture');
 execFileSync('git', ['init', '-q'], { cwd: fixtureRepo });
 execFileSync('git', ['-c', 'user.email=qa@devdeck', '-c', 'user.name=qa', 'add', '-A'], { cwd: fixtureRepo });
 execFileSync('git', ['-c', 'user.email=qa@devdeck', '-c', 'user.name=qa', 'commit', '-q', '-m', 'fixture'], { cwd: fixtureRepo });
 
 async function launch(tag, registerFolder) {
-  const userData = mkdtempSync(join(tmpdir(), `devdeck-close-${tag}-`));
-  const temp = mkdtempSync(join(tmpdir(), `devdeck-closetmp-${tag}-`));
+  const userData = sandboxDir(`devdeck-close-${tag}-`);
+  const temp = sandboxDir(`devdeck-closetmp-${tag}-`);
   const app = await electron.launch({
     args: ['.', `--user-data-dir=${userData}`, '--no-sandbox', '--disable-gpu'],
     cwd: repo,

qa/cockpit-tools.mjs

@@ -10,14 +10,15 @@ import { execFileSync } from 'node:child_process';
 import { tmpdir } from 'node:os';
 import { dirname, join, resolve } from 'node:path';
 import { fileURLToPath } from 'node:url';
+import { sandboxDir } from './sandbox.mjs';
 
 const root = resolve(process.argv[2] ?? dirname(dirname(fileURLToPath(import.meta.url))));
 if (process.platform !== 'win32') { console.log('SKIP: Windows native PTY required'); process.exit(0); }
 const shots = resolve(process.argv[3] ?? join(root, 'qa', 'shots', 'cockpit-tools'));
 mkdirSync(shots, { recursive: true });
 const { closeElectron } = await import('file:///' + join(root, 'qa', 'electron-lifecycle.mjs').replace(/\\/g, '/'));
 
-const sandbox = mkdtempSync(join(tmpdir(), 'devdeck-cockpit-tools-'));
+const sandbox = sandboxDir('devdeck-cockpit-tools-');
 const repo = join(sandbox, 'tools-workspace');
 const bin = join(sandbox, 'bin');
 const profile = join(sandbox, 'profile');

qa/image-rows.mjs

@@ -10,14 +10,15 @@ import { execFileSync } from 'node:child_process';
 import { tmpdir } from 'node:os';
 import { dirname, join, resolve } from 'node:path';
 import { fileURLToPath } from 'node:url';
+import { sandboxDir } from './sandbox.mjs';
 
 const root = resolve(process.argv[2] ?? dirname(dirname(fileURLToPath(import.meta.url))));
 if (process.platform !== 'win32') { console.log('SKIP: Windows native PTY required'); process.exit(0); }
 const shots = resolve(process.argv[3] ?? join(root, 'qa', 'shots', 'image-rows'));
 mkdirSync(shots, { recursive: true });
 const { closeElectron } = await import('file:///' + join(root, 'qa', 'electron-lifecycle.mjs').replace(/\\/g, '/'));
 
-const sandbox = mkdtempSync(join(tmpdir(), 'devdeck-image-rows-'));
+const sandbox = sandboxDir('devdeck-image-rows-');
 const repo = join(sandbox, 'rows-workspace');
 const bin = join(sandbox, 'bin');
 const profile = join(sandbox, 'profile');

qa/images-remote.mjs

@@ -11,11 +11,12 @@ import { tmpdir } from 'node:os';
 import { dirname, join, resolve } from 'node:path';
 import { fileURLToPath } from 'node:url';
 import { closeElectron } from './electron-lifecycle.mjs';
+import { sandboxDir } from './sandbox.mjs';
 
 const root = dirname(dirname(fileURLToPath(import.meta.url)));
 const shots = resolve(process.env.DEVDECK_IMAGES_OUT || join(root, 'qa', 'shots', 'images-remote'));
 mkdirSync(shots, { recursive: true });
-const sandbox = mkdtempSync(join(tmpdir(), 'devdeck-images-remote-'));
+const sandbox = sandboxDir('devdeck-images-remote-');
 const repo = join(sandbox, 'host-workspace');
 const bin = join(sandbox, 'bin');
 for (const p of [repo, bin]) mkdirSync(p, { recursive: true });
@@ -146,7 +147,7 @@ try {
 
   await check('a Claude in Chrome screenshot in the host temp directory travels; other temp files do not', async () => {
     const shotDir = mkdtempSync(join(tmpdir(), 'claude-chrome-screenshots-'));
-    const other = mkdtempSync(join(tmpdir(), 'devdeck-qa-other-'));
+    const other = sandboxDir('devdeck-qa-other-');
     copyFileSync(join(root, 'build', 'icon.png'), join(shotDir, 'screenshot-1-1.jpg'));
     copyFileSync(join(root, 'build', 'icon.png'), join(other, 'shot.png'));
     try {

qa/images.mjs

@@ -7,14 +7,15 @@ import { execFileSync } from 'node:child_process';
 import { tmpdir } from 'node:os';
 import { dirname, join, resolve } from 'node:path';
 import { fileURLToPath } from 'node:url';
+import { sandboxDir } from './sandbox.mjs';
 
 // Windows harness (fixture claude.cmd on PATH). Run with npm run qa:images.
 const root = resolve(process.argv[2] ?? dirname(dirname(fileURLToPath(import.meta.url))));
 const shots = resolve(process.argv[3] ?? join(root, 'qa', 'shots', 'images'));
 mkdirSync(shots, { recursive: true });
 const { closeElectron } = await import('file:///' + join(root, 'qa', 'electron-lifecycle.mjs').replace(/\\/g, '/'));
 
-const sandbox = mkdtempSync(join(tmpdir(), 'devdeck-images-'));
+const sandbox = sandboxDir('devdeck-images-');
 const repo = join(sandbox, 'image-workspace');
 const bin = join(sandbox, 'bin');
 const profile = join(sandbox, 'profile');

qa/link.mjs

@@ -16,6 +16,7 @@ import { dirname, join } from 'node:path';
 import { connect as netConnect } from 'node:net';
 import { fileURLToPath } from 'node:url';
 import { closeElectron } from './electron-lifecycle.mjs';
+import { sandboxDir } from './sandbox.mjs';
 
 const repo = dirname(dirname(fileURLToPath(import.meta.url)));
 
@@ -25,7 +26,7 @@ const repo = dirname(dirname(fileURLToPath(import.meta.url)));
 // child processes down with it (renderer, GPU, network service, exit code -1, no dump). Bisected
 // across five builds before the pattern showed: every run from a worktree passed, every run from the
 // checkout crashed. A fresh repo has no conversation to continue.
-const fixtureRepo = mkdtempSync(join(tmpdir(), 'devdeck-link-fixture-'));
+const fixtureRepo = sandboxDir('devdeck-link-fixture-');
 writeFileSync(join(fixtureRepo, 'README.md'), '# fixture');
 execFileSync('git', ['init', '-q'], { cwd: fixtureRepo });
 execFileSync('git', ['-c', 'user.email=qa@devdeck', '-c', 'user.name=qa', 'add', '-A'], { cwd: fixtureRepo });
@@ -34,12 +35,12 @@ execFileSync('git', ['-c', 'user.email=qa@devdeck', '-c', 'user.name=qa', 'commi
 async function launch(tag, registerFolder, reuse = null) {
   // A relaunch keeps its user-data directory: that is where the machine's identity, its pairings and
   // its port live, and "the host came back" is only meaningful if it comes back as the same machine.
-  const userData = reuse?.userData ?? mkdtempSync(join(tmpdir(), `devdeck-rc-${tag}-`));
+  const userData = reuse?.userData ?? sandboxDir(`devdeck-rc-${tag}-`);
   // Its own temp directory. Both instances run against one filesystem here, so a pasted image landing
   // in the HOST's temp dir is the only thing that distinguishes "the bytes crossed the link and the
   // machine running the agent wrote the file" from "the local paste ran and typed a path that machine
   // cannot read" — which is the whole failure this feature exists to avoid, and it is silent.
-  const temp = reuse?.temp ?? mkdtempSync(join(tmpdir(), `devdeck-tmp-${tag}-`));
+  const temp = reuse?.temp ?? sandboxDir(`devdeck-tmp-${tag}-`);
   const app = await electron.launch({
     args: ['.', `--user-data-dir=${userData}`, '--no-sandbox', '--disable-gpu'],
     cwd: repo,

qa/perf-gate.mjs

@@ -23,6 +23,7 @@ import { tmpdir } from 'node:os';
 import { dirname, join, resolve } from 'node:path';
 import { fileURLToPath } from 'node:url';
 import { closeElectron } from './electron-lifecycle.mjs';
+import { sandboxDir } from './sandbox.mjs';
 
 const root = dirname(dirname(fileURLToPath(import.meta.url)));
 const out = resolve(process.env.DEVDECK_PERF_OUT || join(root, 'qa', 'shots', 'perf-gate'));
@@ -41,7 +42,7 @@ const LIMITS = {
   streamSeconds: 45,          // the stream must finish drawing at all
 };
 
-const sandbox = mkdtempSync(join(tmpdir(), 'devdeck-perf-gate-'));
+const sandbox = sandboxDir('devdeck-perf-gate-');
 const repo = join(sandbox, 'perf-workspace');
 const bin = join(sandbox, 'bin');
 const profile = join(sandbox, 'profile');

qa/perf.mjs

@@ -19,14 +19,15 @@ import { mkdtempSync, writeFileSync } from 'node:fs';
 import { tmpdir } from 'node:os';
 import { dirname, join } from 'node:path';
 import { fileURLToPath } from 'node:url';
+import { sandboxDir } from './sandbox.mjs';
 
 const root = dirname(dirname(fileURLToPath(import.meta.url)));
 const SESSIONS = Number(process.argv[2] ?? 4);
 assert.ok(Number.isInteger(SESSIONS) && SESSIONS >= 1 && SESSIONS <= 16, 'request 1–16 sessions');
 if (!process.argv.includes('--allow-live-agents')) throw new Error('Manual live-agent benchmark. Pass --allow-live-agents explicitly; do not run unattended.');
 const IDLE_MS = 10_000;
 
-const qaUserData = mkdtempSync(join(tmpdir(), 'devdeck-perf-'));
+const qaUserData = sandboxDir('devdeck-perf-');
 writeFileSync(join(qaUserData, 'state.json'), JSON.stringify({
   projects: {}, settings: { folders: [{ path: root, kind: 'repo' }], viewMode: 'list', cockpitSessions: [] },
 }, null, 2));

qa/restore-pacing.mjs

@@ -11,10 +11,11 @@ import { tmpdir } from 'node:os';
 import { dirname, join } from 'node:path';
 import { fileURLToPath } from 'node:url';
 import { closeElectron } from './electron-lifecycle.mjs';
+import { sandboxDir } from './sandbox.mjs';
 
 const root = dirname(dirname(fileURLToPath(import.meta.url)));
 if (process.platform !== 'win32') { console.log('SKIP: Windows native PTY required'); process.exit(0); }
-const sandbox = mkdtempSync(join(tmpdir(), 'devdeck-restore-pacing-'));
+const sandbox = sandboxDir('devdeck-restore-pacing-');
 const repo = join(sandbox, 'pacing-workspace');
 const bin = join(sandbox, 'bin');
 const profile = join(sandbox, 'profile');

qa/sandbox.mjs

@@ -0,0 +1,24 @@
+// Temp folders a harness run works in. Every run used to leave its own behind (about 5 GB after a
+// few weeks). A passing run removes them on exit; a failing one keeps them and says where.
+import { mkdtempSync, rmSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+
+const made = [];
+
+/** A new folder in the OS temp directory, named `<prefix><random>`, removed when the run passes. */
+export function sandboxDir(prefix) {
+  const dir = mkdtempSync(join(tmpdir(), prefix));
+  made.push(dir);
+  return dir;
+}
+
+process.on('exit', (code) => {
+  if (code) {
+    if (made.length) console.log('kept for inspection: ' + made.join(', '));
+    return;
+  }
+  for (const dir of made) {
+    try { rmSync(dir, { recursive: true, force: true, maxRetries: 3, retryDelay: 100 }); } catch { /* still held; temp is swept by the OS */ }
+  }
+});

src/main/diagnostics.test.ts

@@ -1,10 +1,12 @@
-import { describe, it, expect } from 'vitest';
-import { mkdtempSync, writeFileSync, readFileSync, existsSync } from 'node:fs';
+import { afterAll, describe, it, expect } from 'vitest';
+import { mkdtempSync, writeFileSync, readFileSync, existsSync, rmSync } from 'node:fs';
 import { tmpdir } from 'node:os';
 import { join } from 'node:path';
 import { DiagnosticsLog, adoptLegacyErrorLog, formatDiagLine } from './diagnostics';
 
-const dir = (): string => mkdtempSync(join(tmpdir(), 'devdeck-diag-'));
+const made: string[] = [];
+const dir = (): string => { const d = mkdtempSync(join(tmpdir(), 'devdeck-diag-')); made.push(d); return d; };
+afterAll(() => { for (const d of made) rmSync(d, { recursive: true, force: true, maxRetries: 3 }); });
 const at = new Date('2026-08-26T01:02:03.000Z');
 
 describe('formatDiagLine', () => {