Import AITURK IDE 1.0.0-beta.1 from Hermes 63279301; preserve MIT license

apps/desktop/scripts/perf/lib/baseline.mjs

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+// Baseline + regression gate. This is the capability the old one-off scripts
+// never had: measured numbers are compared against a committed baseline so a
+// PR that regresses streaming/typing/mount cost fails loudly instead of
+// silently drifting.
+//
+// Every tracked metric is "lower is better" (longtask counts, frame/keystroke
+// percentiles, mount ms). A metric regresses when it exceeds
+// `baseline * (1 + tolFrac) + tolAbs`. tolAbs absorbs sub-millisecond jitter on
+// already-fast metrics so they don't false-positive.
+
+import { readFileSync, writeFileSync } from 'node:fs'
+
+const DEFAULT_TOLERANCE = { tolFrac: 0.25, tolAbs: 1 }
+
+export function loadBaseline(path) {
+  try {
+    return JSON.parse(readFileSync(path, 'utf8'))
+  } catch {
+    return { _meta: {}, scenarios: {} }
+  }
+}
+
+/**
+ * Compare a scenario's measured metrics against the baseline.
+ * @returns {{ rows: Array, regressed: boolean }}
+ */
+export function compareScenario(name, measured, baseline) {
+  const base = baseline.scenarios?.[name]
+  const tol = { ...DEFAULT_TOLERANCE, ...(base?.tolerance ?? {}) }
+  const rows = []
+  let regressed = false
+
+  for (const [metric, value] of Object.entries(measured)) {
+    if (typeof value !== 'number') {
+      continue
+    }
+
+    const baseValue = base?.metrics?.[metric]
+
+    if (typeof baseValue !== 'number') {
+      rows.push({ metric, measured: value, baseline: null, limit: null, status: 'new' })
+
+      continue
+    }
+
+    const limit = baseValue * (1 + tol.tolFrac) + tol.tolAbs
+    const over = value > limit
+    regressed = regressed || over
+
+    rows.push({
+      metric,
+      measured: value,
+      baseline: baseValue,
+      limit: Math.round(limit * 100) / 100,
+      deltaPct: baseValue ? Math.round(((value - baseValue) / baseValue) * 1000) / 10 : null,
+      status: over ? 'REGRESSED' : 'ok'
+    })
+  }
+
+  return { rows, regressed }
+}
+
+/** Write measured metrics back as the new baseline for the given scenarios. */
+export function updateBaseline(path, results) {
+  const baseline = loadBaseline(path)
+  baseline.scenarios ??= {}
+
+  for (const { name, metrics } of results) {
+    const numeric = Object.fromEntries(Object.entries(metrics).filter(([, v]) => typeof v === 'number'))
+    const prev = baseline.scenarios[name] ?? {}
+    baseline.scenarios[name] = { ...prev, metrics: numeric }
+  }
+
+  baseline._meta = {
+    ...baseline._meta,
+    updated: new Date().toISOString(),
+    platform: `${process.platform}-${process.arch}`,
+    node: process.version
+  }
+
+  writeFileSync(path, `${JSON.stringify(baseline, null, 2)}\n`)
+}
+
+export { DEFAULT_TOLERANCE }