source snapshot 2026-09-02

tests/e2e/sustained-agent-typing-load-scripts.ts

@@ -0,0 +1,135 @@
+/**
+ * Script generators for the multi-workspace sustained typing-latency bench
+ * (terminal-multi-workspace-typing-latency.spec.ts):
+ *
+ * - a paced agent-TUI load generator that replays the deterministic pipeline
+ *   bench fixture through a real PTY at a fixed byte rate, emulating a Claude
+ *   Code-style agent streaming in another workspace, and
+ * - a typing echo probe that timestamps each keystroke's arrival at the pty
+ *   into a sidecar JSONL, so a key's total latency decomposes into
+ *   input-half (CDP keydown -> pty stdin) and echo-half (pty echo -> screen).
+ */
+import { mkdirSync, writeFileSync } from 'node:fs'
+import path from 'node:path'
+import { pathToFileURL } from 'node:url'
+
+// Why absolute file URL: the generated .mjs scripts run with the disposable
+// test repo as cwd, so the fixture builder must be imported by absolute
+// specifier (file URL keeps Windows drive-letter paths importable).
+const PIPELINE_BENCH_URL = pathToFileURL(
+  path.resolve(__dirname, '..', '..', 'tools', 'benchmarks', 'terminal-pipeline-bench.mjs')
+).href
+
+export function sustainedLoadReadyFilePath(
+  directory: string,
+  runId: string,
+  paneIndex: number
+): string {
+  return path.join(directory, `.orca-mwt-load-ready-${runId}-${paneIndex}`)
+}
+
+export function typingProbeReadyMarker(runId: string): string {
+  return `MWT_TYPING_READY_${runId}`
+}
+
+export function typingKeyMarkerPrefix(runId: string): string {
+  return `MWT_KEY_${runId}_`
+}
+
+function sustainedAgentLoadScript(runId: string, readyFileDirectory: string): string {
+  return `
+import { writeFileSync } from 'node:fs'
+import { buildFixture } from ${JSON.stringify(PIPELINE_BENCH_URL)}
+
+const paneIndex = Number(process.argv[2] ?? 0)
+const rateKbps = Number(process.argv[3] ?? 256)
+const durationS = Number(process.argv[4] ?? 60)
+
+const cols = process.stdout.columns ?? 80
+const rows = process.stdout.rows ?? 24
+// 2MB of deterministic Claude-Code-shaped frames, replayed in a loop.
+const fixture = buildFixture('agent-tui', 2 * 1024 * 1024, cols, rows)
+
+const TICK_MS = 50
+const chunkChars = Math.max(1, Math.floor((rateKbps * 1024 * TICK_MS) / 1000))
+const writeChunk = (data) =>
+  new Promise((resolve) => {
+    if (process.stdout.write(data)) {
+      resolve()
+    } else {
+      process.stdout.once('drain', resolve)
+    }
+  })
+const sleep = (ms) => new Promise((resolve) => setTimeout(resolve, ms))
+
+// Readiness signals via the filesystem, not the terminal buffer: with many
+// panes the stream scrolls a READY marker out of the buffer's serialize
+// window before the spec's sequential checks reach it.
+writeFileSync(
+  ${JSON.stringify(readyFileDirectory)} + '/.orca-mwt-load-ready-${runId}-' + paneIndex,
+  String(Date.now())
+)
+process.stdout.write('${'MWT_LOAD_READY_'}${runId}_' + paneIndex + '\\r\\n')
+const deadline = Date.now() + durationS * 1000
+let offset = 0
+while (Date.now() < deadline) {
+  await writeChunk(fixture.slice(offset, offset + chunkChars))
+  offset = (offset + chunkChars) % fixture.length
+  await sleep(TICK_MS)
+}
+process.stdout.write('\\x1b[0m\\x1b[?2026l\\r\\nMWT_LOAD_DONE_${runId}_' + paneIndex + '\\r\\n')
+`
+}
+
+function typingEchoProbeScript(runId: string, arrivalSidecarPath: string): string {
+  return `
+import { appendFileSync } from 'node:fs'
+
+process.stdin.setEncoding('utf8')
+if (process.stdin.isTTY) process.stdin.setRawMode(true)
+process.stdin.resume()
+let seq = 0
+const interrupt = String.fromCharCode(3)
+process.stdout.write('${'MWT_TYPING_READY_'}${runId}\\r\\n')
+process.stdin.on('data', (chunk) => {
+  // One arrival timestamp per chunk: coalesced keystrokes genuinely arrive
+  // together at the pty, and that coalescing is part of what we measure.
+  const atMs = Date.now()
+  if (chunk.includes(interrupt)) {
+    process.exit(0)
+  }
+  for (const char of chunk) {
+    if (char === '\\r' || char === '\\n') continue
+    seq += 1
+    appendFileSync(
+      ${JSON.stringify(arrivalSidecarPath)},
+      JSON.stringify({ seq, atMs }) + '\\n'
+    )
+    process.stdout.write('\\r\\x1b[2Kmwt prompt ' + seq + ': ' + char + ' ${'MWT_KEY_'}${runId}_' + seq + '\\r\\n')
+  }
+})
+`
+}
+
+export function writeSustainedAgentLoadScript(
+  scriptPath: string,
+  runId: string,
+  readyFileDirectory: string
+): void {
+  mkdirSync(path.dirname(scriptPath), { recursive: true })
+  // Generated scripts concatenate with '/', which Node's fs accepts on all
+  // platforms; normalize Windows backslashes out of the baked-in directory.
+  writeFileSync(
+    scriptPath,
+    sustainedAgentLoadScript(runId, readyFileDirectory.replaceAll('\\', '/'))
+  )
+}
+
+export function writeTypingEchoProbeScript(
+  scriptPath: string,
+  runId: string,
+  arrivalSidecarPath: string
+): void {
+  mkdirSync(path.dirname(scriptPath), { recursive: true })
+  writeFileSync(scriptPath, typingEchoProbeScript(runId, arrivalSidecarPath))
+}