Replace CJS-only build with ESM and CJS w/o NODE_ENV

package.json

@@ -2,24 +2,23 @@
   "name": "react-ssr-prepass",
   "version": "1.3.0",
   "description": "A custom partial React SSR renderer for prefetching and suspense",
-  "main": "index.js",
+  "main": "dist/react-ssr-prepass.js",
+  "module": "dist/react-ssr-prepass.es.js",
+  "types": "dist/react-ssr-prepass.d.ts",
   "author": "Phil Plückthun <phil.pluckthun@formidable.com>",
   "license": "MIT",
   "repository": "git@github.com:FormidableLabs/react-ssr-prepass.git",
   "bugs": {
     "url": "https://github.com/FormidableLabs/react-ssr-prepass/issues"
   },
   "files": [
-    "index.js",
-    "index.js.flow",
-    "dist",
-    "index.d.ts"
+    "dist"
   ],
   "sideEffects": false,
-  "types": "index.d.ts",
   "scripts": {
     "prepublishOnly": "run-s flow test build",
     "build": "rollup -c rollup.config.js",
+    "postbuild": "node ./scripts/copy-typings.js",
     "test": "jest",
     "flow": "flow check"
   },
@@ -54,17 +53,16 @@
   },
   "devDependencies": {
     "@ampproject/rollup-plugin-closure-compiler": "^0.26.0",
-    "@babel/core": "^7.13.1",
+    "@babel/core": "^7.13.10",
     "@babel/plugin-transform-flow-strip-types": "^7.13.0",
     "@babel/plugin-transform-object-assign": "^7.12.13",
-    "@babel/preset-env": "^7.13.5",
+    "@babel/preset-env": "^7.13.10",
     "@babel/preset-flow": "^7.12.13",
     "@babel/preset-react": "^7.12.13",
     "@rollup/plugin-babel": "^5.3.0",
     "@rollup/plugin-buble": "^0.21.3",
     "@rollup/plugin-commonjs": "^17.1.0",
     "@rollup/plugin-node-resolve": "^11.2.0",
-    "@rollup/plugin-replace": "^2.3.4",
     "babel-plugin-closure-elimination": "^1.3.2",
     "babel-plugin-transform-async-to-promises": "^0.8.15",
     "codecov": "^3.8.1",
@@ -76,7 +74,7 @@
     "prettier": "^2.2.1",
     "react": "^17.0.1",
     "react-dom": "^17.0.1",
-    "rollup": "^2.39.1",
+    "rollup": "^2.41.2",
     "rollup-plugin-babel": "^4.4.0",
     "rollup-plugin-terser": "^7.0.2"
   }

rollup.config.js

@@ -2,7 +2,6 @@ import commonjs from '@rollup/plugin-commonjs'
 import resolve from '@rollup/plugin-node-resolve'
 import buble from '@rollup/plugin-buble'
 import babel from '@rollup/plugin-babel'
-import replace from '@rollup/plugin-replace'
 import { terser } from 'rollup-plugin-terser'
 import compiler from '@ampproject/rollup-plugin-closure-compiler'
 
@@ -26,48 +25,7 @@ const externalTest = (id) => {
   return externalPredicate.test(id)
 }
 
-const terserPretty = terser({
-  warnings: true,
-  ecma: 5,
-  keep_fnames: true,
-  ie8: false,
-  compress: {
-    pure_getters: true,
-    toplevel: true,
-    booleans_as_integers: false,
-    keep_fnames: true,
-    keep_fargs: true,
-    if_return: false,
-    ie8: false,
-    sequences: false,
-    loops: false,
-    conditionals: false,
-    join_vars: false
-  },
-  mangle: false,
-  output: {
-    beautify: true,
-    braces: true,
-    indent_level: 2
-  }
-})
-
-const terserMinified = terser({
-  warnings: true,
-  ecma: 5,
-  ie8: false,
-  toplevel: true,
-  compress: {
-    keep_infinity: true,
-    pure_getters: true,
-    passes: 10
-  },
-  output: {
-    comments: false
-  }
-})
-
-const makePlugins = (isProduction = false) => [
+const plugins = [
   babel({
     babelrc: false,
     babelHelpers: 'bundled',
@@ -113,54 +71,58 @@ const makePlugins = (isProduction = false) => [
       ]
     ]
   }),
-  isProduction &&
-    replace({
-      'process.env.NODE_ENV': JSON.stringify('production')
-    }),
-  isProduction &&
-    compiler({
-      compilation_level: 'SIMPLE_OPTIMIZATIONS'
-    }),
-  isProduction ? terserMinified : terserPretty
+  compiler({
+    compilation_level: 'SIMPLE_OPTIMIZATIONS'
+  }),
+  terser({
+    warnings: true,
+    ecma: 5,
+    keep_fnames: true,
+    ie8: false,
+    compress: {
+      pure_getters: true,
+      toplevel: true,
+      booleans_as_integers: false,
+      keep_fnames: true,
+      keep_fargs: true,
+      if_return: false,
+      ie8: false,
+      sequences: false,
+      loops: false,
+      conditionals: false,
+      join_vars: false
+    },
+    mangle: false,
+    output: {
+      beautify: true,
+      braces: true,
+      indent_level: 2
+    }
+  })
 ]
 
-const config = {
+export default {
   input: './src/index.js',
   onwarn: () => {},
   external: externalTest,
   treeshake: {
     propertyReadSideEffects: false
-  }
-}
-
-const name = 'react-ssr-prepass'
-
-export default [
-  {
-    ...config,
-    plugins: makePlugins(false),
-    output: [
-      {
-        sourcemap: true,
-        legacy: true,
-        freeze: false,
-        esModule: false,
-        file: `./dist/${name}.development.js`,
-        format: 'cjs'
-      }
-    ]
   },
-  {
-    ...config,
-    plugins: makePlugins(true),
-    output: [
-      {
-        sourcemap: true,
-        legacy: true,
-        freeze: false,
-        file: `./dist/${name}.production.min.js`,
-        format: 'cjs'
-      }
-    ]
-  }
-]
+  plugins,
+  output: [
+    {
+      sourcemap: true,
+      freeze: false,
+      // NOTE: *.mjs files will lead to issues since react is still a non-ESM package
+      // the same goes for package.json:exports
+      file: './dist/react-ssr-prepass.es.js',
+      format: 'esm'
+    },
+    {
+      sourcemap: true,
+      freeze: false,
+      file: './dist/react-ssr-prepass.js',
+      format: 'cjs'
+    }
+  ]
+}

scripts/copy-typings.js

@@ -0,0 +1,19 @@
+#!/usr/bin/env node
+
+const path = require('path')
+const fs = require('fs')
+
+fs.copyFileSync(
+  path.resolve(__dirname, 'react-ssr-prepass.d.ts'),
+  path.resolve(__dirname, '../dist/react-ssr-prepass.d.ts')
+)
+
+fs.copyFileSync(
+  path.resolve(__dirname, 'react-ssr-prepass.js.flow'),
+  path.resolve(__dirname, '../dist/react-ssr-prepass.js.flow')
+)
+
+fs.copyFileSync(
+  path.resolve(__dirname, 'react-ssr-prepass.js.flow'),
+  path.resolve(__dirname, '../dist/react-ssr-prepass.es.js.flow')
+)

src/visitor.js

@@ -79,10 +79,9 @@ const {
 // yielding behavior that gives the event loop a chance to continue
 // running when the prepasses would otherwise take too long
 export const SHOULD_YIELD = typeof setImmediate === 'function'
-
 // Time in ms after which the otherwise synchronous visitor yields so that
 // the event loop is not interrupted for too long
-const YIELD_AFTER_MS = process.env.NODE_ENV !== 'production' ? 20 : 5
+const YIELD_AFTER_MS = 5
 
 const render = (
   type: ComponentType<DefaultProps> & ComponentStatics,