feat(predictive-echo): Phase 0 codex fixtures, measurements, package scaffolding

Recorder (scripts/dev/record-codex-frames.mjs) captures real codex 0.147 TUI output through the production pipeline (tmux status-off + the codex-mode full strip from session.ts) into JSONL fixtures with keystroke injection points; analyzer replays them through @xterm/headless for the measurements in docs/predictive-echo-plan.md. Composer signature /^> /-style (U+203A), modal and wrapped rows correctly rejected, echo is unstyled default-fg, tmux delivers echo as minimal in-place deltas. Package: types.ts gains optional cursorX/cursorY, getCell, onWriteParsed, onResize (all additive); prediction-renderer.ts renders per-glyph spans keyed by prediction seq; @xterm/headless@^6.0.0 devDep for replay tests. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
2026-10-02 13:39:41 +02:00 · 2026-08-09 04:10:18 +02:00
parent ffccde4f7d
commit 5aa59c70cc
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+#!/usr/bin/env node
+/**
+ * @fileoverview Replays a codex fixture (recorded by record-codex-frames.mjs)
+ * through @xterm/headless and prints the measurements the predictive-echo
+ * design doc records: cursor position + composer-row text at every keystroke
+ * injection point, and the final screen with cursor + baseY state.
+ *
+ * Usage: node scripts/dev/analyze-codex-frames.mjs <fixture.jsonl>
+ */
+import { readFileSync } from 'node:fs';
+import { createRequire } from 'node:module';
+
+const require = createRequire(import.meta.url);
+const { Terminal } = require('@xterm/headless');
+
+const file = process.argv[2];
+if (!file) throw new Error('usage: analyze-codex-frames.mjs <fixture.jsonl>');
+const lines = readFileSync(file, 'utf8').trim().split('\n').map(JSON.parse);
+const meta = lines.shift();
+console.log('meta:', JSON.stringify(meta));
+
+const term = new Terminal({ cols: meta.cols, rows: meta.rows, scrollback: 1000, allowProposedApi: true });
+const write = (data) => new Promise((r) => term.write(data, r));
+
+const snap = () => {
+  const buf = term.buffer.active;
+  const row = buf.getLine(buf.baseY + buf.cursorY);
+  return {
+    cursorX: buf.cursorX,
+    cursorY: buf.cursorY,
+    baseY: buf.baseY,
+    rowText: row ? row.translateToString(true) : null,
+    cursorCell: row?.getCell?.(buf.cursorX)?.getChars() ?? null,
+  };
+};
+
+for (const line of lines) {
+  if (line.keyAt) {
+    const s = snap();
+    console.log(`KEY ${JSON.stringify(line.data)} @ cursor(${s.cursorX},${s.cursorY}) baseY=${s.baseY}`);
+    console.log(`    row: ${JSON.stringify(s.rowText)}`);
+    console.log(`    cell-at-cursor: ${JSON.stringify(s.cursorCell)}`);
+  } else {
+    await write(line.data);
+  }
+}
+
+const final = snap();
+console.log('\nFINAL screen (| marks cursor row/col):');
+const buf = term.buffer.active;
+for (let y = 0; y < meta.rows; y++) {
+  const line = buf.getLine(buf.baseY + y);
+  let text = line ? line.translateToString(true) : '';
+  if (y === final.cursorY) text = text.slice(0, final.cursorX) + '|' + text.slice(final.cursorX);
+  if (text.trim()) console.log(String(y).padStart(3), JSON.stringify(text));
+}
+console.log('cursor:', JSON.stringify(final), 'viewportY:', buf.viewportY);
@@ -0,0 +1,190 @@
+#!/usr/bin/env node
+/**
+ * @fileoverview Records real codex TUI output into JSONL fixtures for the
+ * predictive-echo replay tests (packages/xterm-zerolag-input/test/codex-replay.test.ts).
+ *
+ * The pipeline reproduces production byte-for-byte: codex runs inside tmux
+ * (status off, like tmux-manager.ts sessions) driven through a node-pty client,
+ * and every chunk passes through the SAME full strip session.ts applies to
+ * codex-mode output (alt-screen toggles, \x1b[3J, mouse DECSETs, with the
+ * split-sequence carry). What lands in the fixture is what xterm.js receives.
+ *
+ * Fixture format: line 1 is a meta object {scenario, cols, rows, codexVersion,
+ * recordedAt}; every following line is {delayMs, data} where delayMs is the gap
+ * since the previous chunk and data is the stripped chunk. Keystroke injection
+ * points are recorded as {keyAt: true, data} lines so the replay knows where
+ * predictChar() calls belong.
+ *
+ * Usage: node scripts/dev/record-codex-frames.mjs <scenario|all> [--out <dir>]
+ * Scenarios: type-hello, slash-picker, wrap, streaming-burst, paste-bracketed
+ *
+ * The CODEX_HOME is a throwaway temp dir with a fake auth.json; the fake key is
+ * asserted absent from every recorded byte before the fixture is written.
+ */
+import pty from 'node-pty';
+import { execSync } from 'node:child_process';
+import { mkdtempSync, writeFileSync, mkdirSync, rmSync } from 'node:fs';
+import { join, dirname } from 'node:path';
+import { fileURLToPath } from 'node:url';
+
+const ROOT = join(dirname(fileURLToPath(import.meta.url)), '..', '..');
+const FAKE_KEY = 'sk-test-123';
+const COLS = 100;
+const ROWS = 30;
+const BOOT_WAIT_MS = 4500;
+// NOT under /tmp: codex prints a "Refusing to create helper binaries under
+// temporary dir" warning that embeds the CODEX_HOME path when it lives in /tmp.
+// The repo's gitignored tmp/ avoids both the warning and the path leak.
+const SCRATCH = join(ROOT, 'tmp');
+
+// Mirror of the codex-mode FULL strip in session.ts _handleTerminalOutput().
+function makeStripper() {
+  let carry = '';
+  return (data) => {
+    data = carry + data;
+    carry = '';
+    const splitTail = data.match(/\x1b(?:\[\??[0-9]{0,4})?$/);
+    if (splitTail) {
+      carry = splitTail[0];
+      data = data.slice(0, -splitTail[0].length);
+    }
+    return data
+      .replace(/\x1b\[\?(?:47|1047|1049)[hl]/g, '')
+      .replace(/\x1b\[3J/g, '')
+      .replace(/\x1b\[\?(?:1000|1001|1002|1003|1005|1006|1007)[hl]/g, '');
+  };
+}
+
+// Each step: wait `waitMs` after the previous step, then write `keys` to the pty.
+const SCENARIOS = {
+  'type-hello': [
+    ...'hello'.split('').map((ch, i) => ({ waitMs: i === 0 ? BOOT_WAIT_MS : 90, keys: ch })),
+    { waitMs: 1500, keys: '' },
+  ],
+  'slash-picker': [
+    { waitMs: BOOT_WAIT_MS, keys: '/' },
+    { waitMs: 400, keys: 'm' },
+    { waitMs: 150, keys: 'o' },
+    { waitMs: 1200, keys: '\x1b' },
+    { waitMs: 500, keys: '' },
+  ],
+  wrap: [
+    { waitMs: BOOT_WAIT_MS, keys: '' },
+    ...'the quick brown fox jumps over the lazy dog and keeps running until the composer box has to wrap this line twice over'
+      .split('')
+      .map((ch) => ({ waitMs: 25, keys: ch })),
+    { waitMs: 1500, keys: '' },
+  ],
+  'streaming-burst': [
+    ...'hello'.split('').map((ch, i) => ({ waitMs: i === 0 ? BOOT_WAIT_MS : 40, keys: ch })),
+    { waitMs: 300, keys: '\r' },
+    { waitMs: 5000, keys: '' },
+  ],
+  'paste-bracketed': [
+    { waitMs: BOOT_WAIT_MS, keys: 'a' },
+    { waitMs: 90, keys: 'b' },
+    { waitMs: 400, keys: '\x1b[200~XYZpasted\x1b[201~' },
+    { waitMs: 1500, keys: '' },
+  ],
+  // First-run trust dialog: the modal surface where typed chars must NOT be
+  // predicted (the predictWhen ghost eliminator). Recorded UNTRUSTED so the
+  // dialog actually appears; 'x' exercises typing at a non-composer cursor.
+  'trust-modal': {
+    trusted: false,
+    steps: [
+      { waitMs: BOOT_WAIT_MS, keys: 'x' },
+      { waitMs: 800, keys: '\r' },
+      { waitMs: 2500, keys: '' },
+    ],
+  },
+};
+
+async function record(scenario, outDir) {
+  const spec = SCENARIOS[scenario];
+  if (!spec) throw new Error(`unknown scenario ${scenario}`);
+  const steps = Array.isArray(spec) ? spec : spec.steps;
+  const trusted = Array.isArray(spec) ? true : (spec.trusted ?? true);
+
+  mkdirSync(SCRATCH, { recursive: true });
+  const lab = mkdtempSync(join(SCRATCH, 'codexrec-'));
+  writeFileSync(join(lab, 'auth.json'), JSON.stringify({ OPENAI_API_KEY: FAKE_KEY }));
+  const workdir = mkdtempSync(join(SCRATCH, 'codexrec-work-'));
+  if (trusted) {
+    // Pre-trust the workdir so boot goes straight to the composer instead of
+    // the first-run trust dialog (which trust-modal records deliberately).
+    writeFileSync(join(lab, 'config.toml'), `[projects."${workdir}"]\ntrust_level = "trusted"\n`);
+  }
+  const sock = `codexrec-${process.pid}`;
+  const codexVersion = execSync('codex --version', { encoding: 'utf8' }).trim();
+
+  const lines = [];
+  const strip = makeStripper();
+  let lastChunkAt = null;
+  let recording = true;
+  const proc = pty.spawn(
+    'tmux',
+    ['-L', sock, '-f', '/dev/null', 'new-session', '-s', 'rec', ';', 'set', '-t', 'rec', 'status', 'off'],
+    {
+      name: 'xterm-256color',
+      cols: COLS,
+      rows: ROWS,
+      cwd: workdir,
+      env: { ...process.env, CODEX_HOME: lab, SHELL: '/bin/bash' },
+    }
+  );
+  proc.onData((data) => {
+    if (!recording) return; // teardown frames ([server exited]) stay out
+    const now = performance.now();
+    const stripped = strip(data);
+    if (!stripped) return; // timing folds into the next chunk's delay
+    lines.push({ delayMs: lastChunkAt === null ? 0 : Math.round(now - lastChunkAt), data: stripped });
+    lastChunkAt = now;
+  });
+
+  // tmux session starts with a shell; launch codex in it so the strip pipeline
+  // sees the same attach-then-launch order production uses.
+  await sleep(700);
+  proc.write(`exec codex\r`);
+
+  for (const step of steps) {
+    await sleep(step.waitMs);
+    if (step.keys) {
+      lines.push({ keyAt: true, data: step.keys });
+      proc.write(step.keys);
+    }
+  }
+
+  recording = false;
+  try {
+    execSync(`tmux -L ${sock} kill-server`, { stdio: 'ignore' });
+  } catch {
+    /* already gone */
+  }
+  proc.kill();
+  await sleep(200);
+
+  const allBytes = lines.map((l) => l.data).join('');
+  if (allBytes.includes(FAKE_KEY)) throw new Error(`fixture ${scenario} leaked the fake key; NOT writing`);
+  if (allBytes.includes(lab)) throw new Error(`fixture ${scenario} leaked the lab path; NOT writing`);
+
+  mkdirSync(outDir, { recursive: true });
+  const meta = { scenario, cols: COLS, rows: ROWS, codexVersion, recordedAt: new Date().toISOString() };
+  const out = join(outDir, `${scenario}.jsonl`);
+  writeFileSync(out, [JSON.stringify(meta), ...lines.map((l) => JSON.stringify(l))].join('\n') + '\n');
+  rmSync(lab, { recursive: true, force: true });
+  rmSync(workdir, { recursive: true, force: true });
+  console.log(`${scenario}: ${lines.length} lines -> ${out}`);
+}
+
+function sleep(ms) {
+  return new Promise((r) => setTimeout(r, ms));
+}
+
+const arg = process.argv[2];
+const outIdx = process.argv.indexOf('--out');
+const outDir =
+  outIdx !== -1 ? process.argv[outIdx + 1] : join(ROOT, 'packages', 'xterm-zerolag-input', 'test', 'fixtures', 'codex');
+const wanted = arg === 'all' || !arg ? Object.keys(SCENARIOS) : [arg];
+for (const s of wanted) {
+  await record(s, outDir);
+}