From c5c6b8105c76f13d187f80a90c5eb69de26eebf3 Mon Sep 17 00:00:00 2001
From: Daniel Roe <daniel@roe.dev>
Date: Tue, 21 Jan 2025 13:25:11 +0000
Subject: [PATCH] chore: write metrics to disk for better diffing

---
 debug/plugins/timings-babel.mjs  | 18 +++++++++++++++++-
 debug/plugins/timings-unbuild.ts |  4 +++-
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/debug/plugins/timings-babel.mjs b/debug/plugins/timings-babel.mjs
index 3c5a56236d..59e76b78e6 100644
--- a/debug/plugins/timings-babel.mjs
+++ b/debug/plugins/timings-babel.mjs
@@ -1,8 +1,12 @@
 // @ts-check
 
+import { fileURLToPath } from 'node:url'
+
 import { declare } from '@babel/helper-plugin-utils'
 import { types as t } from '@babel/core'
 
+const metricsPath = fileURLToPath(new URL('../../debug-timings.json', import.meta.url))
+
 // inlined from https://github.com/danielroe/errx
 function captureStackTrace () {
   const IS_ABSOLUTE_RE = /^[/\\](?![/\\])|^[/\\]{2}(?!\.)|^[a-z]:[/\\]/i
@@ -45,7 +49,9 @@ function captureStackTrace () {
   return trace
 }
 
+
 export const leading = `
+import { writeFileSync as ____writeFileSync } from 'node:fs'
 const ___captureStackTrace = ${captureStackTrace.toString()};
 globalThis.___calls ||= {};
 globalThis.___timings ||= {};
@@ -55,6 +61,16 @@ function onExit () {
   if (globalThis.___logged) { return }
   globalThis.___logged = true
 
+  // eslint-disable-next-line no-undef
+  ____writeFileSync(metricsPath, JSON.stringify(Object.fromEntries(Object.entries(globalThis.___timings).map(([name, time]) => [
+    name,
+    {
+      time: Number(Number(time).toFixed(2)),
+      calls: globalThis.___calls[name],
+      callers: globalThis.___callers[name] ? Object.fromEntries(Object.entries(globalThis.___callers[name]).map(([name, count]) => [name.trim(), count]).sort((a, b) => typeof b[0] === 'string' && typeof a[0] === 'string' ? a[0].localeCompare(b[0]) : 0)) : undefined,
+    },
+  ]).sort((a, b) => typeof b[0] === 'string' && typeof a[0] === 'string' ? a[0].localeCompare(b[0]) : 0)), null, 2))
+
   // worst by total time
   const timings = Object.entries(globalThis.___timings)
 
@@ -93,7 +109,7 @@ function onExit () {
   console.table(topFunctionsAverageTime)
 }
 
-export const trailing = `process.on("exit", ${onExit.toString()})`
+export const trailing = `process.on("exit", ${onExit.toString().replace('metricsPath', JSON.stringify(metricsPath))})`
 
 /** @param {string} functionName */
 export function generateInitCode (functionName) {
diff --git a/debug/plugins/timings-unbuild.ts b/debug/plugins/timings-unbuild.ts
index 09574dd347..d1fdd5df8d 100644
--- a/debug/plugins/timings-unbuild.ts
+++ b/debug/plugins/timings-unbuild.ts
@@ -15,6 +15,8 @@ declare global {
   var ___calls: Record<string, number>
   // eslint-disable-next-line no-var
   var ___callers: Record<string, number>
+  // eslint-disable-next-line no-var
+  var ____writeFileSync: typeof import('fs').writeFileSync
 }
 
 export function AnnotateFunctionTimingsPlugin () {
@@ -29,7 +31,7 @@ export function AnnotateFunctionTimingsPlugin () {
           walk(ast as Node, {
             enter (node) {
               if (node.type === 'FunctionDeclaration' && node.id && node.id.name) {
-                const functionName = node.id.name ? `${node.id.name} (${id.match(/\/packages\/([^/]+)\//)?.[1]})` : ''
+                const functionName = node.id.name ? `${node.id.name} (${id.match(/[\\/]packages[\\/]([^/]+)[\\/]/)?.[1]})` : ''
                 const start = (node.body as Node & { start: number, end: number }).start
                 const end = (node.body as Node & { start: number, end: number }).end