build(tooling): [ENG-11] add module analysis without changing artifacts

scripts/build-analysis.mjs

@@ -0,0 +1,44 @@
+import { Buffer } from 'node:buffer'
+import { createHash } from 'node:crypto'
+import fs from 'node:fs'
+import path from 'node:path'
+import process from 'node:process'
+import { gzipSync } from 'node:zlib'
+
+export function createBuildAnalysis() {
+  const root = process.cwd()
+  const parent = path.join(root, 'refactor/.cache/build-analysis')
+  fs.mkdirSync(parent, { recursive: true })
+  const directory = fs.mkdtempSync(path.join(parent, 'run-'))
+  fs.writeFileSync(path.join(parent, 'latest.json'), `${JSON.stringify({ output: path.relative(root, directory).replaceAll('\\', '/') })}\n`)
+  return { root, directory }
+}
+
+export function buildAnalysisPlugin({ root, directory }, name, format) {
+  return {
+    name: 'artplayer-build-analysis',
+    generateBundle(_options, bundle) {
+      for (const chunk of Object.values(bundle).filter(item => item.type === 'chunk')) {
+        const modules = Object.entries(chunk.modules).map(([id, info]) => {
+          const normalized = id.replaceAll('\\', '/')
+          const dependency = normalized.lastIndexOf('/node_modules/')
+          const file = id.startsWith('\0')
+            ? `virtual:${id.slice(1)}`
+            : dependency === -1 ? path.relative(root, id).replaceAll('\\', '/') : normalized.slice(dependency + 1)
+          return { file, renderedBytes: Buffer.byteLength(info.code || ''), renderedCodeUnits: info.renderedLength, originalCodeUnits: info.originalLength, renderedExports: info.renderedExports, removedExports: info.removedExports }
+        }).sort((a, b) => b.renderedBytes - a.renderedBytes || a.file.localeCompare(b.file))
+        const report = {
+          schemaVersion: 1,
+          name,
+          format,
+          node: process.version,
+          file: chunk.fileName,
+          artifact: { bytes: Buffer.byteLength(chunk.code), gzip9: gzipSync(chunk.code, { level: 9 }).length, sha256: createHash('sha256').update(chunk.code).digest('hex') },
+          note: 'Rendered UTF-8 bytes precede final chunk minification; they are not additive compressed sizes or download measurements. Rollup lengths are separately recorded as UTF-16 code units. Original code units describe Rollup input, not raw TypeScript.',
+          modules,
+        }
+        fs.writeFileSync(path.join(directory, `${name}-${format}.json`), `${JSON.stringify(report, null, 2)}\n`)
+      }
+    },
+  }
+}

scripts/build.js

@@ -3,6 +3,7 @@ import path from 'node:path'
 import process from 'node:process'
 import cpy from 'cpy'
 import { build as viteBuild } from 'vite'
+import { buildAnalysisPlugin, createBuildAnalysis } from './build-analysis.mjs'
 import { getEntryFile, selectProjects } from './projects.js'
 import { getGlobalName, getProjects, getViteBuildConfig } from './utils.js'
 
@@ -27,7 +28,7 @@ const BUILD_FORMATS = {
   esm: { format: 'es', ext: '.mjs', target: 'es2020', minify: false },
 }
 
-async function build(name, targetName, clean = false) {
+async function build(name, targetName, clean = false, analysis) {
   const projectDir = projects[name]
   const { version } = JSON.parse(fs.readFileSync(path.join(projectDir, 'package.json'), 'utf-8'))
   const distDir = path.join(projectDir, 'dist')
@@ -67,6 +68,8 @@ async function build(name, targetName, clean = false) {
       max_line_len: false, // No line length limit
     },
   }
+  if (analysis)
+    config.build.rollupOptions.plugins.push(buildAnalysisPlugin(analysis, name, targetName))
 
   await viteBuild({ root: projectDir, ...config })
 
@@ -77,16 +80,19 @@ async function build(name, targetName, clean = false) {
   console.log(`✨ Built@${targetName} ${name}@${version} Time@${Date.now() - startTime}ms Size@${size}kb`)
 }
 
-async function buildProject(name) {
-  await build(name, 'main', true)
-  await build(name, 'legacy')
-  await build(name, 'esm')
+async function buildProject(name, analysis) {
+  await build(name, 'main', true, analysis)
+  await build(name, 'legacy', false, analysis)
+  await build(name, 'esm', false, analysis)
 }
 
 async function runBuild() {
-  const { names } = await selectProjects(projects, 'build')
+  const { names, analyze } = await selectProjects(projects, 'build')
+  const analysis = analyze ? createBuildAnalysis() : undefined
   for (const name of names)
-    await buildProject(name)
+    await buildProject(name, analysis)
+  if (analysis)
+    console.log(`Build analysis: ${analysis.directory}`)
   if (names.length)
     console.log(`✅ Finished building ${names.length} package(s)!`)
 }

scripts/projects.js

@@ -20,9 +20,12 @@ export function getEntryFile(projectDir) {
 export function parseProjects(args, projects, command) {
   const names = []
   let open = true
+  let analyze = false
   for (const arg of args) {
     if (arg === '--no-open' && command === 'dev')
       open = false
+    else if (arg === '--analyze' && command === 'build')
+      analyze = true
     else if (arg === '--help')
       return { help: true, names: [], open }
     else if (arg !== '--')
@@ -31,7 +34,7 @@ export function parseProjects(args, projects, command) {
   if (names.includes('all')) {
     if (command !== 'build' || names.length !== 1)
       throw new Error('Use build all on its own; dev accepts one package')
-    return { names: Object.keys(projects), open }
+    return { names: Object.keys(projects), open, analyze }
   }
   for (const name of names) {
     if (!Object.hasOwn(projects, name))
@@ -39,13 +42,13 @@ export function parseProjects(args, projects, command) {
   }
   if (command === 'dev' && names.length > 1)
     throw new Error('dev accepts one package')
-  return { names: [...new Set(names)], open }
+  return { names: [...new Set(names)], open, analyze }
 }
 
 export async function selectProjects(projects, command) {
   const selection = parseProjects(process.argv.slice(2), projects, command)
   if (selection.help) {
-    console.log(command === 'build' ? 'Usage: yarn build [all | package ...]' : 'Usage: yarn dev [package] [--no-open]')
+    console.log(command === 'build' ? 'Usage: yarn build [all | package ...] [--analyze]' : 'Usage: yarn dev [package] [--no-open]')
     return selection
   }
   if (!selection.names.length) {