From 265b3c0188d34ac6785e4c615fb5f78aab558307 Mon Sep 17 00:00:00 2001
From: Dustan Kasten <dustan.kasten@gmail.com>
Date: Wed, 20 Sep 2017 09:29:36 -0400
Subject: [PATCH 01/25] Initial commit of react-reconciler bundle

---
 packages/react-reconciler/README.md    | 16 ++++++++++++
 packages/react-reconciler/index.js     |  7 ++++++
 packages/react-reconciler/package.json | 35 ++++++++++++++++++++++++++
 scripts/rollup/bundles.js              | 26 +++++++++++++++++++
 4 files changed, 84 insertions(+)
 create mode 100644 packages/react-reconciler/README.md
 create mode 100644 packages/react-reconciler/index.js
 create mode 100644 packages/react-reconciler/package.json

diff --git a/packages/react-reconciler/README.md b/packages/react-reconciler/README.md
new file mode 100644
index 0000000000000..740a4f2c064d2
--- /dev/null
+++ b/packages/react-reconciler/README.md
@@ -0,0 +1,16 @@
+# react
+
+An npm package to get you immediate access to [React](https://facebook.github.io/react/),
+without also requiring the JSX transformer. This is especially useful for cases where you
+want to [`browserify`](https://github.com/substack/node-browserify) your module using
+`React`.
+
+**Note:** by default, React will be in development mode. The development version includes extra warnings about common mistakes, whereas the production version includes extra performance optimizations and strips all error messages.
+
+To use React in production mode, set the environment variable `NODE_ENV` to `production`. A minifier that performs dead-code elimination such as [UglifyJS](https://github.com/mishoo/UglifyJS2) is recommended to completely remove the extra code present in development mode.
+
+## Example Usage
+
+```js
+var React = require('react');
+```
diff --git a/packages/react-reconciler/index.js b/packages/react-reconciler/index.js
new file mode 100644
index 0000000000000..28d36c9d30df1
--- /dev/null
+++ b/packages/react-reconciler/index.js
@@ -0,0 +1,7 @@
+'use strict';
+
+if (process.env.NODE_ENV === 'production') {
+  module.exports = require('./cjs/react-reconciler.production.min.js');
+} else {
+  module.exports = require('./cjs/react-reconciler.development.js');
+}
diff --git a/packages/react-reconciler/package.json b/packages/react-reconciler/package.json
new file mode 100644
index 0000000000000..89697d252a390
--- /dev/null
+++ b/packages/react-reconciler/package.json
@@ -0,0 +1,35 @@
+{
+  "name": "react-reconciler",
+  "description": "React is a JavaScript library for building user interfaces.",
+  "version": "16.0.0-rc.2",
+  "keywords": [
+    "react"
+  ],
+  "homepage": "https://facebook.github.io/react/",
+  "bugs": "https://github.com/facebook/react/issues",
+  "license": "BSD-3-Clause",
+  "files": [
+    "LICENSE",
+    "PATENTS",
+    "README.md",
+    "index.js",
+    "cjs/",
+    "umd/"
+  ],
+  "main": "index.js",
+  "repository": "facebook/react",
+  "engines": {
+    "node": ">=0.10.0"
+  },
+  "dependencies": {
+    "fbjs": "^0.8.9",
+    "loose-envify": "^1.1.0",
+    "object-assign": "^4.1.0",
+    "prop-types": "^15.5.6"
+  },
+  "browserify": {
+    "transform": [
+      "loose-envify"
+    ]
+  }
+}
diff --git a/scripts/rollup/bundles.js b/scripts/rollup/bundles.js
index a8e536eb11399..9b5ecd52eee41 100644
--- a/scripts/rollup/bundles.js
+++ b/scripts/rollup/bundles.js
@@ -401,6 +401,32 @@ const bundles = [
       'src/shared/**/*.js',
     ],
   },
+
+  /******* React Reconciler *******/
+  {
+    babelOpts: babelOptsReact,
+    bundleTypes: [NODE_DEV, NODE_PROD],
+    config: {
+      destDir: 'build/',
+      globals: {
+        react: 'React',
+      },
+      moduleName: 'ReactReconciler',
+      sourceMap: false,
+    },
+    entry: 'src/renderers/shared/fiber/ReactFiberReconciler',
+    externals: ['react', 'prop-types/checkPropTypes'],
+    isRenderer: false,
+    label: 'react-reconciler',
+    manglePropertiesOnProd: false,
+    name: 'react-reconciler',
+    paths: [
+      'src/renderers/shared/**/*.js',
+
+      'src/ReactVersion.js',
+      'src/shared/**/*.js',
+    ],
+  },
 ];
 
 // Based on deep-freeze by substack (public domain)

From 21853d5e6bbe967037844e348afcfcd84ccf55f5 Mon Sep 17 00:00:00 2001
From: Dustan Kasten <dustan.kasten@gmail.com>
Date: Wed, 20 Sep 2017 11:01:31 -0400
Subject: [PATCH 02/25] =?UTF-8?q?I=20think=20it=E2=80=99s=20working=20?=
 =?UTF-8?q?=F0=9F=99=80?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 fixtures/reconciler/README.md          |  16 ++++
 fixtures/reconciler/index.js           |  10 +++
 fixtures/reconciler/package.json       |  13 +++
 fixtures/reconciler/yarn.lock          | 107 +++++++++++++++++++++++++
 packages/react-reconciler/package.json |   3 +
 scripts/rollup/build.js                |  22 +++--
 6 files changed, 166 insertions(+), 5 deletions(-)
 create mode 100644 fixtures/reconciler/README.md
 create mode 100644 fixtures/reconciler/index.js
 create mode 100644 fixtures/reconciler/package.json
 create mode 100644 fixtures/reconciler/yarn.lock

diff --git a/fixtures/reconciler/README.md b/fixtures/reconciler/README.md
new file mode 100644
index 0000000000000..6798d09f5f248
--- /dev/null
+++ b/fixtures/reconciler/README.md
@@ -0,0 +1,16 @@
+
+To test, run:
+* `yarn install` 
+* edit node_modules/react-reconciler/cjs/react-reconciler.development.js 
+* Add the below snipper after `var valueStack = [];`
+* `yarn test`
+
+If everything is okay then you should see `Ok!` printed to the console.
+
+
+```
+if (global.valueStacks === undefined) {
+  global.valueStacks = [];
+}
+global.valueStacks.push(valueStack);
+```
diff --git a/fixtures/reconciler/index.js b/fixtures/reconciler/index.js
new file mode 100644
index 0000000000000..53f93c8a60b18
--- /dev/null
+++ b/fixtures/reconciler/index.js
@@ -0,0 +1,10 @@
+const React = require('react');
+const Reconciler = require('react-reconciler');
+const assert = require('assert');
+const A = Reconciler({});
+const B = Reconciler({});
+
+assert(global.valueStacks.length === 2);
+assert(global.valueStacks[0] !== global.valueStacks[1]);
+console.log('Ok!');
+
diff --git a/fixtures/reconciler/package.json b/fixtures/reconciler/package.json
new file mode 100644
index 0000000000000..a288c1e22963b
--- /dev/null
+++ b/fixtures/reconciler/package.json
@@ -0,0 +1,13 @@
+{
+  "name": "react-fixtures",
+  "version": "0.1.0",
+  "private": true,
+  "dependencies": {
+    "react": "^16.0.0-",
+    "react-reconciler": "file:../../build/packages/react-reconciler"
+  },
+  "scripts": {
+    "start": "../../node_modules/.bin/babel-node ./index",
+    "test": "../../node_modules/.bin/babel-node ./index"
+  }
+}
diff --git a/fixtures/reconciler/yarn.lock b/fixtures/reconciler/yarn.lock
new file mode 100644
index 0000000000000..64bb62652dcfa
--- /dev/null
+++ b/fixtures/reconciler/yarn.lock
@@ -0,0 +1,107 @@
+# THIS IS AN AUTOGENERATED FILE. DO NOT EDIT THIS FILE DIRECTLY.
+# yarn lockfile v1
+
+
+asap@~2.0.3:
+  version "2.0.6"
+  resolved "https://registry.yarnpkg.com/asap/-/asap-2.0.6.tgz#e50347611d7e690943208bbdafebcbc2fb866d46"
+
+core-js@^1.0.0:
+  version "1.2.7"
+  resolved "https://registry.yarnpkg.com/core-js/-/core-js-1.2.7.tgz#652294c14651db28fa93bd2d5ff2983a4f08c636"
+
+encoding@^0.1.11:
+  version "0.1.12"
+  resolved "https://registry.yarnpkg.com/encoding/-/encoding-0.1.12.tgz#538b66f3ee62cd1ab51ec323829d1f9480c74beb"
+  dependencies:
+    iconv-lite "~0.4.13"
+
+fbjs@^0.8.9:
+  version "0.8.15"
+  resolved "https://registry.yarnpkg.com/fbjs/-/fbjs-0.8.15.tgz#4f0695fdfcc16c37c0b07facec8cb4c4091685b9"
+  dependencies:
+    core-js "^1.0.0"
+    isomorphic-fetch "^2.1.1"
+    loose-envify "^1.0.0"
+    object-assign "^4.1.0"
+    promise "^7.1.1"
+    setimmediate "^1.0.5"
+    ua-parser-js "^0.7.9"
+
+iconv-lite@~0.4.13:
+  version "0.4.19"
+  resolved "https://registry.yarnpkg.com/iconv-lite/-/iconv-lite-0.4.19.tgz#f7468f60135f5e5dad3399c0a81be9a1603a082b"
+
+is-stream@^1.0.1:
+  version "1.1.0"
+  resolved "https://registry.yarnpkg.com/is-stream/-/is-stream-1.1.0.tgz#12d4a3dd4e68e0b79ceb8dbc84173ae80d91ca44"
+
+isomorphic-fetch@^2.1.1:
+  version "2.2.1"
+  resolved "https://registry.yarnpkg.com/isomorphic-fetch/-/isomorphic-fetch-2.2.1.tgz#611ae1acf14f5e81f729507472819fe9733558a9"
+  dependencies:
+    node-fetch "^1.0.1"
+    whatwg-fetch ">=0.10.0"
+
+js-tokens@^3.0.0:
+  version "3.0.2"
+  resolved "https://registry.yarnpkg.com/js-tokens/-/js-tokens-3.0.2.tgz#9866df395102130e38f7f996bceb65443209c25b"
+
+loose-envify@^1.0.0, loose-envify@^1.1.0, loose-envify@^1.3.1:
+  version "1.3.1"
+  resolved "https://registry.yarnpkg.com/loose-envify/-/loose-envify-1.3.1.tgz#d1a8ad33fa9ce0e713d65fdd0ac8b748d478c848"
+  dependencies:
+    js-tokens "^3.0.0"
+
+node-fetch@^1.0.1:
+  version "1.7.3"
+  resolved "https://registry.yarnpkg.com/node-fetch/-/node-fetch-1.7.3.tgz#980f6f72d85211a5347c6b2bc18c5b84c3eb47ef"
+  dependencies:
+    encoding "^0.1.11"
+    is-stream "^1.0.1"
+
+object-assign@^4.1.0:
+  version "4.1.1"
+  resolved "https://registry.yarnpkg.com/object-assign/-/object-assign-4.1.1.tgz#2109adc7965887cfc05cbbd442cac8bfbb360863"
+
+promise@^7.1.1:
+  version "7.3.1"
+  resolved "https://registry.yarnpkg.com/promise/-/promise-7.3.1.tgz#064b72602b18f90f29192b8b1bc418ffd1ebd3bf"
+  dependencies:
+    asap "~2.0.3"
+
+prop-types@^15.5.6:
+  version "15.5.10"
+  resolved "https://registry.yarnpkg.com/prop-types/-/prop-types-15.5.10.tgz#2797dfc3126182e3a95e3dfbb2e893ddd7456154"
+  dependencies:
+    fbjs "^0.8.9"
+    loose-envify "^1.3.1"
+
+"react-reconciler@file:../../build/packages/react-reconciler":
+  version "16.0.0"
+  dependencies:
+    fbjs "^0.8.9"
+    loose-envify "^1.1.0"
+    object-assign "^4.1.0"
+    prop-types "^15.5.6"
+
+react@^16.0.0-:
+  version "16.0.0-rc.3"
+  resolved "https://registry.yarnpkg.com/react/-/react-16.0.0-rc.3.tgz#4a9df996326ba7185903d9fbed3149765e237e26"
+  dependencies:
+    fbjs "^0.8.9"
+    loose-envify "^1.1.0"
+    object-assign "^4.1.0"
+    prop-types "^15.5.6"
+
+setimmediate@^1.0.5:
+  version "1.0.5"
+  resolved "https://registry.yarnpkg.com/setimmediate/-/setimmediate-1.0.5.tgz#290cbb232e306942d7d7ea9b83732ab7856f8285"
+
+ua-parser-js@^0.7.9:
+  version "0.7.14"
+  resolved "https://registry.yarnpkg.com/ua-parser-js/-/ua-parser-js-0.7.14.tgz#110d53fa4c3f326c121292bbeac904d2e03387ca"
+
+whatwg-fetch@>=0.10.0:
+  version "2.0.3"
+  resolved "https://registry.yarnpkg.com/whatwg-fetch/-/whatwg-fetch-2.0.3.tgz#9c84ec2dcf68187ff00bc64e1274b442176e1c84"
diff --git a/packages/react-reconciler/package.json b/packages/react-reconciler/package.json
index 89697d252a390..594393cf3f0d2 100644
--- a/packages/react-reconciler/package.json
+++ b/packages/react-reconciler/package.json
@@ -21,6 +21,9 @@
   "engines": {
     "node": ">=0.10.0"
   },
+  "peerDependencies": {
+    "react": "^16.0.0-beta.3"
+  },
   "dependencies": {
     "fbjs": "^0.8.9",
     "loose-envify": "^1.1.0",
diff --git a/scripts/rollup/build.js b/scripts/rollup/build.js
index de66907c96ff3..aacb53254b52e 100644
--- a/scripts/rollup/build.js
+++ b/scripts/rollup/build.js
@@ -79,6 +79,7 @@ function getHeaderSanityCheck(bundleType, hasteName) {
 }
 
 function getBanner(bundleType, hasteName, filename) {
+  const isReconciler = /react-reconciler/.test(filename);
   switch (bundleType) {
     // UMDs are not wrapped in conditions.
     case UMD_DEV:
@@ -89,10 +90,15 @@ function getBanner(bundleType, hasteName, filename) {
       let banner = Header.getHeader(filename, reactVersion);
       // Wrap the contents of the if-DEV check with an IIFE.
       // Block-level function definitions can cause problems for strict mode.
-      banner += `'use strict';\n\n\nif (process.env.NODE_ENV !== "production") {\n(function() {\n`;
+      banner += isReconciler
+        ? `'use strict';\n\n\nif (process.env.NODE_ENV !== "production") {\nmodule.exports = function(config) {\n`
+        : `'use strict';\n\n\nif (process.env.NODE_ENV !== "production") {\n(function() {\n`;
       return banner;
     case NODE_PROD:
-      return Header.getHeader(filename, reactVersion);
+      return (
+        Header.getHeader(filename, reactVersion) +
+        (isReconciler ? `\n\n'use strict';\n\n\nmodule.exports = function(config) {\n` : '')
+      );
     // All FB and RN bundles need Haste headers.
     // DEV bundle is guarded to help weak dead code elimination.
     case FB_DEV:
@@ -105,14 +111,20 @@ function getBanner(bundleType, hasteName, filename) {
       // Block-level function definitions can cause problems for strict mode.
       return (
         Header.getProvidesHeader(hasteFinalName) +
-        (isDev ? `\n\n'use strict';\n\n\nif (__DEV__) {\n(function() {\n` : '')
+        isDev ? `\n\n'use strict';\n\n\nif (__DEV__) {\n(function() {\n` : ''
       );
     default:
       throw new Error('Unknown type.');
   }
 }
 
-function getFooter(bundleType) {
+function getFooter(bundleType, filename) {
+  if (/react-reconciler/.test(filename)) {
+    return (
+      '\nreturn ReactFiberReconciler(config);\n};\n' +
+      (bundleType === NODE_DEV ? '}\n' : '')
+    );
+  }
   // Only need a footer if getBanner() has an opening brace.
   switch (bundleType) {
     // Non-UMD DEV bundles need conditions to help weak dead code elimination.
@@ -125,7 +137,7 @@ function getFooter(bundleType) {
   }
 }
 
-function updateBabelConfig(babelOpts, bundleType) {
+function updateBabelConfig(babelOpts, bundleType, filename) {
   switch (bundleType) {
     case FB_DEV:
     case FB_PROD:

From 703c5124877433ea68c704deda8da34f04146856 Mon Sep 17 00:00:00 2001
From: Dustan Kasten <dustan.kasten@gmail.com>
Date: Wed, 20 Sep 2017 11:43:49 -0400
Subject: [PATCH 03/25] React reconciler: slightly better description and
 README

---
 packages/react-reconciler/README.md    | 37 +++++++++++++++++++-------
 packages/react-reconciler/package.json |  2 +-
 2 files changed, 28 insertions(+), 11 deletions(-)

diff --git a/packages/react-reconciler/README.md b/packages/react-reconciler/README.md
index 740a4f2c064d2..8d84ff562b9bd 100644
--- a/packages/react-reconciler/README.md
+++ b/packages/react-reconciler/README.md
@@ -1,16 +1,33 @@
-# react
+# react-reconciler
 
-An npm package to get you immediate access to [React](https://facebook.github.io/react/),
-without also requiring the JSX transformer. This is especially useful for cases where you
-want to [`browserify`](https://github.com/substack/node-browserify) your module using
-`React`.
-
-**Note:** by default, React will be in development mode. The development version includes extra warnings about common mistakes, whereas the production version includes extra performance optimizations and strips all error messages.
-
-To use React in production mode, set the environment variable `NODE_ENV` to `production`. A minifier that performs dead-code elimination such as [UglifyJS](https://github.com/mishoo/UglifyJS2) is recommended to completely remove the extra code present in development mode.
+An npm package to let you create custom reconcilers.
 
 ## Example Usage
 
 ```js
-var React = require('react');
+var createReconciler = require('react-reconciler');
+
+var ReconcilerConfig = { /* ... */ };
+var Reconciler = createReconciler(ReconcilerConfig);
+var Renderer = {
+  render(
+    element: React$Element<any>,
+    container: DOMContainer,
+    callback: ?Function,
+  ) {
+    let root = container._reactRootContainer;
+    if (!root) {
+      const newRoot = Renderer.createContainer(container);
+      root = container._reactRootContainer = newRoot;
+      // Initial mount should not be batched.
+      Renderer.unbatchedUpdates(() => {
+        Renderer.updateContainer(element, newRoot, null, callback);
+      });
+    } else {
+      Renderer.updateContainer(element, root, null, callback);
+    }
+  }
+};
+
+module.exports = Renderer;
 ```
diff --git a/packages/react-reconciler/package.json b/packages/react-reconciler/package.json
index 594393cf3f0d2..dbd74516b0dca 100644
--- a/packages/react-reconciler/package.json
+++ b/packages/react-reconciler/package.json
@@ -1,6 +1,6 @@
 {
   "name": "react-reconciler",
-  "description": "React is a JavaScript library for building user interfaces.",
+  "description": "React package for creating custom reconcilers.",
   "version": "16.0.0-rc.2",
   "keywords": [
     "react"

From d4deee80e61fb1f7ace009d0bef32bd461ed05d9 Mon Sep 17 00:00:00 2001
From: Dustan Kasten <dustan.kasten@gmail.com>
Date: Thu, 21 Sep 2017 08:37:37 -0400
Subject: [PATCH 04/25] Drop react-reconciler version to an unstable release
 number

---
 packages/react-reconciler/package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/react-reconciler/package.json b/packages/react-reconciler/package.json
index dbd74516b0dca..0019bb3748b2f 100644
--- a/packages/react-reconciler/package.json
+++ b/packages/react-reconciler/package.json
@@ -1,7 +1,7 @@
 {
   "name": "react-reconciler",
   "description": "React package for creating custom reconcilers.",
-  "version": "16.0.0-rc.2",
+  "version": "0.1.0",
   "keywords": [
     "react"
   ],

From a64e9e9e2b4751c12e8f2370eef5ff30db764daa Mon Sep 17 00:00:00 2001
From: Dustan Kasten <dustan.kasten@gmail.com>
Date: Thu, 21 Sep 2017 08:49:13 -0400
Subject: [PATCH 05/25] Convert to moduleType enum and fix packaging

---
 scripts/rollup/build.js   | 37 ++++++++++++++++++++++---------------
 scripts/rollup/bundles.js | 35 +++++++++++++++++++++++------------
 scripts/rollup/modules.js | 16 +++++++++++-----
 3 files changed, 56 insertions(+), 32 deletions(-)

diff --git a/scripts/rollup/build.js b/scripts/rollup/build.js
index aacb53254b52e..575eb3a3bd9e8 100644
--- a/scripts/rollup/build.js
+++ b/scripts/rollup/build.js
@@ -34,6 +34,10 @@ const FB_PROD = Bundles.bundleTypes.FB_PROD;
 const RN_DEV = Bundles.bundleTypes.RN_DEV;
 const RN_PROD = Bundles.bundleTypes.RN_PROD;
 
+const ISOMORPHIC = Bundles.moduleTypes.ISOMORPHIC;
+const RENDERER = Bundles.moduleTypes.RENDERER;
+const RECONCILER = Bundles.moduleTypes.RECONCILER;
+
 const reactVersion = require('../../package.json').version;
 const requestedBundleTypes = (argv.type || '')
   .split(',')
@@ -78,8 +82,7 @@ function getHeaderSanityCheck(bundleType, hasteName) {
   }
 }
 
-function getBanner(bundleType, hasteName, filename) {
-  const isReconciler = /react-reconciler/.test(filename);
+function getBanner(bundleType, hasteName, filename, moduleType) {
   switch (bundleType) {
     // UMDs are not wrapped in conditions.
     case UMD_DEV:
@@ -90,15 +93,18 @@ function getBanner(bundleType, hasteName, filename) {
       let banner = Header.getHeader(filename, reactVersion);
       // Wrap the contents of the if-DEV check with an IIFE.
       // Block-level function definitions can cause problems for strict mode.
-      banner += isReconciler
+      banner += moduleType === RECONCILER
         ? `'use strict';\n\n\nif (process.env.NODE_ENV !== "production") {\nmodule.exports = function(config) {\n`
         : `'use strict';\n\n\nif (process.env.NODE_ENV !== "production") {\n(function() {\n`;
       return banner;
     case NODE_PROD:
       return (
         Header.getHeader(filename, reactVersion) +
-        (isReconciler ? `\n\n'use strict';\n\n\nmodule.exports = function(config) {\n` : '')
+        (moduleType === RECONCILER
+         ? `\n\n'use strict';\n\n\nmodule.exports = function(config) {\n`
+        : '')
       );
+
     // All FB and RN bundles need Haste headers.
     // DEV bundle is guarded to help weak dead code elimination.
     case FB_DEV:
@@ -111,15 +117,15 @@ function getBanner(bundleType, hasteName, filename) {
       // Block-level function definitions can cause problems for strict mode.
       return (
         Header.getProvidesHeader(hasteFinalName) +
-        isDev ? `\n\n'use strict';\n\n\nif (__DEV__) {\n(function() {\n` : ''
+        (isDev ? `\n\n'use strict';\n\n\nif (__DEV__) {\n(function() {\n` : '')
       );
     default:
       throw new Error('Unknown type.');
   }
 }
 
-function getFooter(bundleType, filename) {
-  if (/react-reconciler/.test(filename)) {
+function getFooter(bundleType, filename, moduleType) {
+  if (moduleType === RECONCILER) {
     return (
       '\nreturn ReactFiberReconciler(config);\n};\n' +
       (bundleType === NODE_DEV ? '}\n' : '')
@@ -178,16 +184,16 @@ function handleRollupWarnings(warning) {
   console.warn(warning.message || warning);
 }
 
-function updateBundleConfig(config, filename, format, bundleType, hasteName) {
+function updateBundleConfig(config, filename, format, bundleType, hasteName, moduleType) {
   return Object.assign({}, config, {
-    banner: getBanner(bundleType, hasteName, filename),
+    banner: getBanner(bundleType, hasteName, filename, moduleType),
     dest: Packaging.getPackageDestination(
       config,
       bundleType,
       filename,
       hasteName
     ),
-    footer: getFooter(bundleType),
+    footer: getFooter(bundleType, filename, moduleType),
     format,
     interop: false,
   });
@@ -321,7 +327,7 @@ function getPlugins(
   filename,
   bundleType,
   hasteName,
-  isRenderer,
+  moduleType,
   manglePropertiesOnProd,
   useFiber,
   modulesToStub
@@ -329,7 +335,7 @@ function getPlugins(
   const plugins = [
     babel(updateBabelConfig(babelOpts, bundleType)),
     alias(
-      Modules.getAliases(paths, bundleType, isRenderer, argv['extract-errors'])
+      Modules.getAliases(paths, bundleType, moduleType, argv['extract-errors'])
     ),
   ];
 
@@ -465,7 +471,7 @@ function createBundle(bundle, bundleType) {
     external: Modules.getExternalModules(
       bundle.externals,
       bundleType,
-      bundle.isRenderer
+      bundle.moduleType
     ),
     onwarn: handleRollupWarnings,
     plugins: getPlugins(
@@ -475,7 +481,7 @@ function createBundle(bundle, bundleType) {
       filename,
       bundleType,
       bundle.hasteName,
-      bundle.isRenderer,
+      bundle.moduleType,
       bundle.manglePropertiesOnProd,
       bundle.useFiber,
       bundle.modulesToStub
@@ -488,7 +494,8 @@ function createBundle(bundle, bundleType) {
           filename,
           format,
           bundleType,
-          bundle.hasteName
+          bundle.hasteName,
+          bundle.moduleType
         )
       )
     )
diff --git a/scripts/rollup/bundles.js b/scripts/rollup/bundles.js
index 9b5ecd52eee41..6ba9f3dd4aee2 100644
--- a/scripts/rollup/bundles.js
+++ b/scripts/rollup/bundles.js
@@ -20,6 +20,16 @@ const FB_PROD = bundleTypes.FB_PROD;
 const RN_DEV = bundleTypes.RN_DEV;
 const RN_PROD = bundleTypes.RN_PROD;
 
+const moduleTypes = {
+  ISOMORPHIC: 'ISOMORPHIC',
+  RENDERER: 'RENDERER',
+  RECONCILER: 'RECONCILER',
+};
+
+const ISOMORPHIC = moduleTypes.ISOMORPHIC;
+const RENDERER = moduleTypes.RENDERER;
+const RECONCILER = moduleTypes.RECONCILER;
+
 const babelOptsReact = {
   exclude: 'node_modules/**',
   presets: [],
@@ -51,7 +61,7 @@ const bundles = [
     ],
     fbEntry: 'src/isomorphic/ReactEntry',
     hasteName: 'React',
-    isRenderer: false,
+    moduleType: ISOMORPHIC,
     label: 'core',
     manglePropertiesOnProd: false,
     name: 'react',
@@ -79,7 +89,7 @@ const bundles = [
     externals: ['prop-types', 'prop-types/checkPropTypes'],
     fbEntry: 'src/fb/ReactDOMFiberFBEntry',
     hasteName: 'ReactDOMFiber',
-    isRenderer: true,
+    moduleType: RENDERER,
     label: 'dom-fiber',
     manglePropertiesOnProd: false,
     name: 'react-dom',
@@ -112,7 +122,7 @@ const bundles = [
     ],
     fbEntry: 'src/renderers/dom/test/ReactTestUtilsEntry',
     hasteName: 'ReactTestUtils',
-    isRenderer: true,
+    moduleType: RENDERER,
     label: 'test-utils',
     manglePropertiesOnProd: false,
     name: 'react-dom/test-utils',
@@ -147,7 +157,7 @@ const bundles = [
     ],
     fbEntry: 'src/renderers/dom/shared/ReactDOMUnstableNativeDependenciesEntry',
     hasteName: 'ReactDOMUnstableNativeDependencies',
-    isRenderer: false,
+    moduleType: RENDERER,
     label: 'dom-unstable-native-dependencies',
     manglePropertiesOnProd: false,
     name: 'react-dom/unstable-native-dependencies',
@@ -176,7 +186,7 @@ const bundles = [
     externals: ['prop-types', 'prop-types/checkPropTypes'],
     fbEntry: 'src/renderers/dom/ReactDOMServerBrowserEntry',
     hasteName: 'ReactDOMServer',
-    isRenderer: true,
+    moduleType: RENDERER,
     label: 'dom-server-browser',
     manglePropertiesOnProd: false,
     name: 'react-dom/server.browser',
@@ -201,7 +211,7 @@ const bundles = [
     },
     entry: 'src/renderers/dom/ReactDOMServerNodeEntry',
     externals: ['prop-types', 'prop-types/checkPropTypes', 'stream'],
-    isRenderer: true,
+    moduleType: RENDERER,
     label: 'dom-server-server-node',
     manglePropertiesOnProd: false,
     name: 'react-dom/server.node',
@@ -237,7 +247,7 @@ const bundles = [
     ],
     fbEntry: 'src/renderers/art/ReactARTFiberEntry',
     hasteName: 'ReactARTFiber',
-    isRenderer: true,
+    moduleType: RENDERER,
     label: 'art-fiber',
     manglePropertiesOnProd: false,
     name: 'react-art',
@@ -274,7 +284,7 @@ const bundles = [
       'prop-types/checkPropTypes',
     ],
     hasteName: 'ReactNativeFiber',
-    isRenderer: true,
+    moduleType: RENDERER,
     label: 'native-fiber',
     manglePropertiesOnProd: false,
     name: 'react-native-renderer',
@@ -335,7 +345,7 @@ const bundles = [
     externals: ['prop-types/checkPropTypes'],
     fbEntry: 'src/renderers/testing/ReactTestRendererFiberEntry',
     hasteName: 'ReactTestRendererFiber',
-    isRenderer: true,
+    moduleType: RENDERER,
     label: 'test-fiber',
     manglePropertiesOnProd: false,
     name: 'react-test-renderer',
@@ -364,7 +374,7 @@ const bundles = [
     ],
     fbEntry: 'src/renderers/testing/ReactShallowRendererEntry',
     hasteName: 'ReactShallowRenderer',
-    isRenderer: true,
+    moduleType: RENDERER,
     label: 'shallow-renderer',
     manglePropertiesOnProd: false,
     name: 'react-test-renderer/shallow',
@@ -389,7 +399,7 @@ const bundles = [
     },
     entry: 'src/renderers/noop/ReactNoopEntry',
     externals: ['prop-types/checkPropTypes', 'jest-matchers'],
-    isRenderer: true,
+    moduleType: RENDERER,
     label: 'noop-fiber',
     manglePropertiesOnProd: false,
     name: 'react-noop-renderer',
@@ -416,7 +426,7 @@ const bundles = [
     },
     entry: 'src/renderers/shared/fiber/ReactFiberReconciler',
     externals: ['react', 'prop-types/checkPropTypes'],
-    isRenderer: false,
+    moduleType: RECONCILER,
     label: 'react-reconciler',
     manglePropertiesOnProd: false,
     name: 'react-reconciler',
@@ -449,5 +459,6 @@ deepFreeze(bundles);
 
 module.exports = {
   bundleTypes,
+  moduleTypes,
   bundles,
 };
diff --git a/scripts/rollup/modules.js b/scripts/rollup/modules.js
index 53918d536a5d5..8d0edfecb261a 100644
--- a/scripts/rollup/modules.js
+++ b/scripts/rollup/modules.js
@@ -4,6 +4,7 @@ const resolve = require('path').resolve;
 const basename = require('path').basename;
 const sync = require('glob').sync;
 const bundleTypes = require('./bundles').bundleTypes;
+const moduleTypes = require('./bundles').moduleTypes;
 const extractErrorCodes = require('../error-codes/extract-errors');
 
 const exclude = [
@@ -21,6 +22,10 @@ const FB_PROD = bundleTypes.FB_PROD;
 const RN_DEV = bundleTypes.RN_DEV;
 const RN_PROD = bundleTypes.RN_PROD;
 
+const ISOMORPHIC = moduleTypes.ISOMORPHIC;
+const RENDERER = moduleTypes.RENDERER;
+const RECONCILER = moduleTypes.RECONCILER;
+
 const errorCodeOpts = {
   errorMapFilePath: 'scripts/error-codes/codes.json',
 };
@@ -87,7 +92,7 @@ function createModuleMap(paths, extractErrors, bundleType) {
   return moduleMap;
 }
 
-function getNodeModules(bundleType, isRenderer) {
+function getNodeModules(bundleType, moduleType) {
   // rather than adding the rollup node resolve plugin,
   // we can instead deal with the only node module that is used
   // for UMD bundles - object-assign
@@ -97,7 +102,7 @@ function getNodeModules(bundleType, isRenderer) {
       return {
         // Bundle object-assign once in the isomorphic React, and then use
         // that from the renderer UMD. Avoids bundling it in both UMDs.
-        'object-assign': isRenderer
+        'object-assign': moduleType === RENDERER
           ? resolve('./scripts/rollup/shims/rollup/assign.js')
           : resolve('./node_modules/object-assign/index.js'),
         // include the ART package modules directly by aliasing them from node_modules
@@ -136,7 +141,7 @@ function ignoreReactNativeModules() {
   ];
 }
 
-function getExternalModules(externals, bundleType, isRenderer) {
+function getExternalModules(externals, bundleType, moduleType) {
   // external modules tell Rollup that we should not attempt
   // to bundle these modules and instead treat them as
   // external dependencies to the bundle. so for CJS bundles
@@ -144,6 +149,7 @@ function getExternalModules(externals, bundleType, isRenderer) {
   // the top of the bundle. for UMD bundles this means having
   // both a require and a global check for them
   let externalModules = externals.slice();
+  const isRenderer = moduleType === RENDERER || moduleType === RECONCILER;
 
   switch (bundleType) {
     case UMD_DEV:
@@ -282,7 +288,7 @@ function replaceBundleStubModules(bundleModulesToStub) {
   return stubbedModules;
 }
 
-function getAliases(paths, bundleType, isRenderer, extractErrors) {
+function getAliases(paths, bundleType, moduleType, extractErrors) {
   return Object.assign(
     createModuleMap(
       paths,
@@ -290,7 +296,7 @@ function getAliases(paths, bundleType, isRenderer, extractErrors) {
       bundleType
     ),
     getInternalModules(),
-    getNodeModules(bundleType, isRenderer),
+    getNodeModules(bundleType, moduleType),
     getFbjsModuleAliases(bundleType)
   );
 }

From ac1e6034df3146f4969535e38d6558334a3f716b Mon Sep 17 00:00:00 2001
From: Dustan Kasten <dustan.kasten@gmail.com>
Date: Thu, 21 Sep 2017 13:51:13 -0400
Subject: [PATCH 06/25] eslint

---
 scripts/rollup/build.js   | 2 --
 scripts/rollup/modules.js | 1 -
 2 files changed, 3 deletions(-)

diff --git a/scripts/rollup/build.js b/scripts/rollup/build.js
index 575eb3a3bd9e8..d26e859185db9 100644
--- a/scripts/rollup/build.js
+++ b/scripts/rollup/build.js
@@ -34,8 +34,6 @@ const FB_PROD = Bundles.bundleTypes.FB_PROD;
 const RN_DEV = Bundles.bundleTypes.RN_DEV;
 const RN_PROD = Bundles.bundleTypes.RN_PROD;
 
-const ISOMORPHIC = Bundles.moduleTypes.ISOMORPHIC;
-const RENDERER = Bundles.moduleTypes.RENDERER;
 const RECONCILER = Bundles.moduleTypes.RECONCILER;
 
 const reactVersion = require('../../package.json').version;
diff --git a/scripts/rollup/modules.js b/scripts/rollup/modules.js
index 8d0edfecb261a..3ab8b668c9814 100644
--- a/scripts/rollup/modules.js
+++ b/scripts/rollup/modules.js
@@ -22,7 +22,6 @@ const FB_PROD = bundleTypes.FB_PROD;
 const RN_DEV = bundleTypes.RN_DEV;
 const RN_PROD = bundleTypes.RN_PROD;
 
-const ISOMORPHIC = moduleTypes.ISOMORPHIC;
 const RENDERER = moduleTypes.RENDERER;
 const RECONCILER = moduleTypes.RECONCILER;
 

From 1165ee87f3df178c8ce68bc9ae90482bd4f63824 Mon Sep 17 00:00:00 2001
From: Dustan Kasten <dustan.kasten@gmail.com>
Date: Fri, 22 Sep 2017 10:36:23 -0400
Subject: [PATCH 07/25] s/Renderer/Reconciler in docs

---
 packages/react-reconciler/README.md | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/packages/react-reconciler/README.md b/packages/react-reconciler/README.md
index 8d84ff562b9bd..b3d579f50c1a0 100644
--- a/packages/react-reconciler/README.md
+++ b/packages/react-reconciler/README.md
@@ -17,14 +17,14 @@ var Renderer = {
   ) {
     let root = container._reactRootContainer;
     if (!root) {
-      const newRoot = Renderer.createContainer(container);
+      const newRoot = Reconciler.createContainer(container);
       root = container._reactRootContainer = newRoot;
       // Initial mount should not be batched.
-      Renderer.unbatchedUpdates(() => {
-        Renderer.updateContainer(element, newRoot, null, callback);
+      Reconciler.unbatchedUpdates(() => {
+        Reconciler.updateContainer(element, newRoot, null, callback);
       });
     } else {
-      Renderer.updateContainer(element, root, null, callback);
+      Reconciler.updateContainer(element, root, null, callback);
     }
   }
 };

From 2018b79ccffdf7534215da67d9a9c3963731ad56 Mon Sep 17 00:00:00 2001
From: Dustan Kasten <dustan.kasten@gmail.com>
Date: Fri, 22 Sep 2017 10:38:54 -0400
Subject: [PATCH 08/25] yarn prettier

---
 fixtures/reconciler/index.js |  1 -
 scripts/rollup/build.js      | 14 ++++++++++----
 2 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/fixtures/reconciler/index.js b/fixtures/reconciler/index.js
index 53f93c8a60b18..89b1630a89a8c 100644
--- a/fixtures/reconciler/index.js
+++ b/fixtures/reconciler/index.js
@@ -7,4 +7,3 @@ const B = Reconciler({});
 assert(global.valueStacks.length === 2);
 assert(global.valueStacks[0] !== global.valueStacks[1]);
 console.log('Ok!');
-
diff --git a/scripts/rollup/build.js b/scripts/rollup/build.js
index d26e859185db9..d9c3e0db57f68 100644
--- a/scripts/rollup/build.js
+++ b/scripts/rollup/build.js
@@ -99,10 +99,9 @@ function getBanner(bundleType, hasteName, filename, moduleType) {
       return (
         Header.getHeader(filename, reactVersion) +
         (moduleType === RECONCILER
-         ? `\n\n'use strict';\n\n\nmodule.exports = function(config) {\n`
-        : '')
+          ? `\n\n'use strict';\n\n\nmodule.exports = function(config) {\n`
+          : '')
       );
-
     // All FB and RN bundles need Haste headers.
     // DEV bundle is guarded to help weak dead code elimination.
     case FB_DEV:
@@ -182,7 +181,14 @@ function handleRollupWarnings(warning) {
   console.warn(warning.message || warning);
 }
 
-function updateBundleConfig(config, filename, format, bundleType, hasteName, moduleType) {
+function updateBundleConfig(
+  config,
+  filename,
+  format,
+  bundleType,
+  hasteName,
+  moduleType
+) {
   return Object.assign({}, config, {
     banner: getBanner(bundleType, hasteName, filename, moduleType),
     dest: Packaging.getPackageDestination(

From 3f7a6b6801f3b9848c83134b8f370d9cef423528 Mon Sep 17 00:00:00 2001
From: Dustan Kasten <dustan.kasten@gmail.com>
Date: Fri, 22 Sep 2017 11:28:19 -0400
Subject: [PATCH 09/25] change names of things in the react-reconciler readme

---
 packages/react-reconciler/README.md | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/packages/react-reconciler/README.md b/packages/react-reconciler/README.md
index b3d579f50c1a0..3d4ce8d9f3770 100644
--- a/packages/react-reconciler/README.md
+++ b/packages/react-reconciler/README.md
@@ -5,11 +5,11 @@ An npm package to let you create custom reconcilers.
 ## Example Usage
 
 ```js
-var createReconciler = require('react-reconciler');
+var Reconciler = require('react-reconciler');
 
 var ReconcilerConfig = { /* ... */ };
-var Reconciler = createReconciler(ReconcilerConfig);
-var Renderer = {
+var Renderer = Reconciler(ReconcilerConfig);
+var RendererPublicAPI = {
   render(
     element: React$Element<any>,
     container: DOMContainer,
@@ -17,17 +17,17 @@ var Renderer = {
   ) {
     let root = container._reactRootContainer;
     if (!root) {
-      const newRoot = Reconciler.createContainer(container);
+      const newRoot = Renderer.createContainer(container);
       root = container._reactRootContainer = newRoot;
       // Initial mount should not be batched.
-      Reconciler.unbatchedUpdates(() => {
-        Reconciler.updateContainer(element, newRoot, null, callback);
+      Renderer.unbatchedUpdates(() => {
+        Renderer.updateContainer(element, newRoot, null, callback);
       });
     } else {
-      Reconciler.updateContainer(element, root, null, callback);
+      Renderer.updateContainer(element, root, null, callback);
     }
   }
 };
 
-module.exports = Renderer;
+module.exports = RendererPublicAPI;
 ```

From b1ace5c8e11db4399c0020e858d1de1d695d3276 Mon Sep 17 00:00:00 2001
From: Dustan Kasten <dustan.kasten@gmail.com>
Date: Mon, 25 Sep 2017 10:05:57 -0400
Subject: [PATCH 10/25] change predicate

---
 scripts/rollup/modules.js | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/scripts/rollup/modules.js b/scripts/rollup/modules.js
index 3ab8b668c9814..8cc8a27821a86 100644
--- a/scripts/rollup/modules.js
+++ b/scripts/rollup/modules.js
@@ -23,7 +23,7 @@ const RN_DEV = bundleTypes.RN_DEV;
 const RN_PROD = bundleTypes.RN_PROD;
 
 const RENDERER = moduleTypes.RENDERER;
-const RECONCILER = moduleTypes.RECONCILER;
+const ISOMORPHIC = moduleTypes.ISOMORPHIC;
 
 const errorCodeOpts = {
   errorMapFilePath: 'scripts/error-codes/codes.json',
@@ -148,12 +148,10 @@ function getExternalModules(externals, bundleType, moduleType) {
   // the top of the bundle. for UMD bundles this means having
   // both a require and a global check for them
   let externalModules = externals.slice();
-  const isRenderer = moduleType === RENDERER || moduleType === RECONCILER;
-
   switch (bundleType) {
     case UMD_DEV:
     case UMD_PROD:
-      if (isRenderer) {
+      if (moduleType !== ISOMORPHIC) {
         externalModules.push('react');
       }
       break;
@@ -163,7 +161,7 @@ function getExternalModules(externals, bundleType, moduleType) {
     case RN_PROD:
       fbjsModules.forEach(module => externalModules.push(module));
       externalModules.push('object-assign');
-      if (isRenderer) {
+      if (moduleType !== ISOMORPHIC) {
         externalModules.push('react');
       }
       break;
@@ -173,7 +171,7 @@ function getExternalModules(externals, bundleType, moduleType) {
       externalModules.push('object-assign');
       externalModules.push('ReactCurrentOwner');
       externalModules.push('lowPriorityWarning');
-      if (isRenderer) {
+      if (moduleType !== ISOMORPHIC) {
         externalModules.push('React');
         if (externalModules.indexOf('react-dom') > -1) {
           externalModules.push('ReactDOM');

From e7d4f44b63366aef614a20fa6a88ef147909545d Mon Sep 17 00:00:00 2001
From: Dustan Kasten <dustan.kasten@gmail.com>
Date: Mon, 25 Sep 2017 10:36:04 -0400
Subject: [PATCH 11/25] rollup: flip object-assign shimming check

---
 scripts/rollup/modules.js | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/scripts/rollup/modules.js b/scripts/rollup/modules.js
index 8cc8a27821a86..7d4effb01965f 100644
--- a/scripts/rollup/modules.js
+++ b/scripts/rollup/modules.js
@@ -22,7 +22,6 @@ const FB_PROD = bundleTypes.FB_PROD;
 const RN_DEV = bundleTypes.RN_DEV;
 const RN_PROD = bundleTypes.RN_PROD;
 
-const RENDERER = moduleTypes.RENDERER;
 const ISOMORPHIC = moduleTypes.ISOMORPHIC;
 
 const errorCodeOpts = {
@@ -101,9 +100,9 @@ function getNodeModules(bundleType, moduleType) {
       return {
         // Bundle object-assign once in the isomorphic React, and then use
         // that from the renderer UMD. Avoids bundling it in both UMDs.
-        'object-assign': moduleType === RENDERER
-          ? resolve('./scripts/rollup/shims/rollup/assign.js')
-          : resolve('./node_modules/object-assign/index.js'),
+        'object-assign': moduleType === ISOMORPHIC
+          ? resolve('./node_modules/object-assign/index.js')
+          : resolve('./scripts/rollup/shims/rollup/assign.js'),
         // include the ART package modules directly by aliasing them from node_modules
         'art/modes/current': resolve('./node_modules/art/modes/current.js'),
         'art/modes/fast-noSideEffects': resolve(

From 34551f7dbfd46646cb8d89d7e9a88c367dc9b92a Mon Sep 17 00:00:00 2001
From: Dustan Kasten <dustan.kasten@gmail.com>
Date: Mon, 25 Sep 2017 17:27:27 -0400
Subject: [PATCH 12/25] copy noop renderer into react-reconciler fixture

---
 fixtures/reconciler/NoopRenderer.js | 470 ++++++++++++++++++++++++++++
 fixtures/reconciler/index.js        |  38 ++-
 2 files changed, 499 insertions(+), 9 deletions(-)
 create mode 100644 fixtures/reconciler/NoopRenderer.js

diff --git a/fixtures/reconciler/NoopRenderer.js b/fixtures/reconciler/NoopRenderer.js
new file mode 100644
index 0000000000000..05e766ae30e83
--- /dev/null
+++ b/fixtures/reconciler/NoopRenderer.js
@@ -0,0 +1,470 @@
+/**
+ * Copyright 2013-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ *
+ * @flow
+ */
+
+/**
+ * This is a renderer of React that doesn't have a render target output.
+ * It is useful to demonstrate the internals of the reconciler in isolation
+ * and for testing semantics of reconciliation separate from the host
+ * environment.
+ */
+
+'use strict';
+
+import type {Fiber} from 'ReactFiber';
+import type {UpdateQueue} from 'ReactFiberUpdateQueue';
+var ReactFiberReconciler = require('react-reconciler');
+var emptyObject = require('fbjs/lib/emptyObject');
+
+var assert = require('assert');
+
+const UPDATE_SIGNAL = {};
+
+var scheduledCallback = null;
+
+type Container = {rootID: string, children: Array<Instance | TextInstance>};
+type Props = {prop: any, hidden?: boolean};
+type Instance = {|
+  type: string,
+  id: number,
+  children: Array<Instance | TextInstance>,
+  prop: any,
+|};
+type TextInstance = {|text: string, id: number|};
+
+var instanceCounter = 0;
+
+var failInBeginPhase = false;
+
+function appendChild(
+  parentInstance: Instance | Container,
+  child: Instance | TextInstance,
+): void {
+  const index = parentInstance.children.indexOf(child);
+  if (index !== -1) {
+    parentInstance.children.splice(index, 1);
+  }
+  parentInstance.children.push(child);
+}
+
+function insertBefore(
+  parentInstance: Instance | Container,
+  child: Instance | TextInstance,
+  beforeChild: Instance | TextInstance,
+): void {
+  const index = parentInstance.children.indexOf(child);
+  if (index !== -1) {
+    parentInstance.children.splice(index, 1);
+  }
+  const beforeIndex = parentInstance.children.indexOf(beforeChild);
+  if (beforeIndex === -1) {
+    throw new Error('This child does not exist.');
+  }
+  parentInstance.children.splice(beforeIndex, 0, child);
+}
+
+function removeChild(
+  parentInstance: Instance | Container,
+  child: Instance | TextInstance,
+): void {
+  const index = parentInstance.children.indexOf(child);
+  if (index === -1) {
+    throw new Error('This child does not exist.');
+  }
+  parentInstance.children.splice(index, 1);
+}
+
+var NoopRenderer = ReactFiberReconciler({
+  getRootHostContext() {
+    if (failInBeginPhase) {
+      throw new Error('Error in host config.');
+    }
+    return emptyObject;
+  },
+
+  getChildHostContext() {
+    return emptyObject;
+  },
+
+  getPublicInstance(instance) {
+    return instance;
+  },
+
+  createInstance(type: string, props: Props): Instance {
+    const inst = {
+      id: instanceCounter++,
+      type: type,
+      children: [],
+      prop: props.prop,
+    };
+    // Hide from unit tests
+    Object.defineProperty(inst, 'id', {value: inst.id, enumerable: false});
+    return inst;
+  },
+
+  appendInitialChild(
+    parentInstance: Instance,
+    child: Instance | TextInstance,
+  ): void {
+    parentInstance.children.push(child);
+  },
+
+  finalizeInitialChildren(
+    domElement: Instance,
+    type: string,
+    props: Props,
+  ): boolean {
+    return false;
+  },
+
+  prepareUpdate(
+    instance: Instance,
+    type: string,
+    oldProps: Props,
+    newProps: Props,
+  ): null | {} {
+    return UPDATE_SIGNAL;
+  },
+
+  commitMount(instance: Instance, type: string, newProps: Props): void {
+    // Noop
+  },
+
+  commitUpdate(
+    instance: Instance,
+    updatePayload: Object,
+    type: string,
+    oldProps: Props,
+    newProps: Props,
+  ): void {
+    instance.prop = newProps.prop;
+  },
+
+  shouldSetTextContent(type: string, props: Props): boolean {
+    return (
+      typeof props.children === 'string' || typeof props.children === 'number'
+    );
+  },
+
+  resetTextContent(instance: Instance): void {},
+
+  shouldDeprioritizeSubtree(type: string, props: Props): boolean {
+    return !!props.hidden;
+  },
+
+  createTextInstance(
+    text: string,
+    rootContainerInstance: Container,
+    hostContext: Object,
+    internalInstanceHandle: Object,
+  ): TextInstance {
+    var inst = {text: text, id: instanceCounter++};
+    // Hide from unit tests
+    Object.defineProperty(inst, 'id', {value: inst.id, enumerable: false});
+    return inst;
+  },
+
+  commitTextUpdate(
+    textInstance: TextInstance,
+    oldText: string,
+    newText: string,
+  ): void {
+    textInstance.text = newText;
+  },
+
+  appendChild: appendChild,
+  appendChildToContainer: appendChild,
+  insertBefore: insertBefore,
+  insertInContainerBefore: insertBefore,
+  removeChild: removeChild,
+  removeChildFromContainer: removeChild,
+
+  scheduleDeferredCallback(callback) {
+    if (scheduledCallback) {
+      throw new Error(
+        'Scheduling a callback twice is excessive. Instead, keep track of ' +
+          'whether the callback has already been scheduled.',
+      );
+    }
+    scheduledCallback = callback;
+  },
+
+  prepareForCommit(): void {},
+
+  resetAfterCommit(): void {},
+});
+
+var rootContainers = new Map();
+var roots = new Map();
+var DEFAULT_ROOT_ID = '<default>';
+
+let yieldedValues = null;
+
+function* flushUnitsOfWork(n: number): Generator<Array<mixed>, void, void> {
+  var didStop = false;
+  while (!didStop && scheduledCallback !== null) {
+    var cb = scheduledCallback;
+    scheduledCallback = null;
+    yieldedValues = null;
+    var unitsRemaining = n;
+    cb({
+      timeRemaining() {
+        if (yieldedValues !== null) {
+          return 0;
+        }
+        if (unitsRemaining-- > 0) {
+          return 999;
+        }
+        didStop = true;
+        return 0;
+      },
+    });
+
+    if (yieldedValues !== null) {
+      const values = yieldedValues;
+      yieldedValues = null;
+      yield values;
+    }
+  }
+}
+
+var ReactNoop = {
+  getChildren(rootID: string = DEFAULT_ROOT_ID) {
+    const container = rootContainers.get(rootID);
+    if (container) {
+      return container.children;
+    } else {
+      return null;
+    }
+  },
+
+  // Shortcut for testing a single root
+  render(element: React$Element<any>, callback: ?Function) {
+    ReactNoop.renderToRootWithID(element, DEFAULT_ROOT_ID, callback);
+  },
+
+  renderToRootWithID(
+    element: React$Element<any>,
+    rootID: string,
+    callback: ?Function,
+  ) {
+    let root = roots.get(rootID);
+    if (!root) {
+      const container = {rootID: rootID, children: []};
+      rootContainers.set(rootID, container);
+      root = NoopRenderer.createContainer(container);
+      roots.set(rootID, root);
+    }
+    NoopRenderer.updateContainer(element, root, null, callback);
+  },
+
+  unmountRootWithID(rootID: string) {
+    const root = roots.get(rootID);
+    if (root) {
+      NoopRenderer.updateContainer(null, root, null, () => {
+        roots.delete(rootID);
+        rootContainers.delete(rootID);
+      });
+    }
+  },
+
+  /* We don’t have access to ReactInstanceMap from the outside
+  findInstance(
+    componentOrElement: Element | ?React$Component<any, any>,
+  ): null | Instance | TextInstance {
+    if (componentOrElement == null) {
+      return null;
+    }
+    // Unsound duck typing.
+    const component = (componentOrElement: any);
+    if (typeof component.id === 'number') {
+      return component;
+    }
+    const inst = ReactInstanceMap.get(component);
+    return inst ? NoopRenderer.findHostInstance(inst) : null;
+  },
+  */
+
+  flushDeferredPri(timeout: number = Infinity): Array<mixed> {
+    // The legacy version of this function decremented the timeout before
+    // returning the new time.
+    // TODO: Convert tests to use flushUnitsOfWork or flushAndYield instead.
+    const n = timeout / 5 - 1;
+
+    let values = [];
+    for (const value of flushUnitsOfWork(n)) {
+      values.push(...value);
+    }
+    return values;
+  },
+
+  flush(): Array<mixed> {
+    return ReactNoop.flushUnitsOfWork(Infinity);
+  },
+
+  flushAndYield(
+    unitsOfWork: number = Infinity,
+  ): Generator<Array<mixed>, void, void> {
+    return flushUnitsOfWork(unitsOfWork);
+  },
+
+  flushUnitsOfWork(n: number): Array<mixed> {
+    let values = [];
+    for (const value of flushUnitsOfWork(n)) {
+      values.push(...value);
+    }
+    return values;
+  },
+
+  flushThrough(expected: Array<mixed>): void {
+    let actual = [];
+    if (expected.length !== 0) {
+      for (const value of flushUnitsOfWork(Infinity)) {
+        actual.push(...value);
+        if (actual.length >= expected.length) {
+          break;
+        }
+      }
+    }
+    assert.deepEqual(
+      actual,
+      expected,
+      'Unexpected flush results.\nExpected:\n  ' + JSON.stringify(actual, null, 2) +
+      '\n\nActual:\n  ' + JSON.stringify(expected, null, 2)
+    );
+  },
+
+  yield(value: mixed) {
+    if (yieldedValues === null) {
+      yieldedValues = [value];
+    } else {
+      yieldedValues.push(value);
+    }
+  },
+
+  hasScheduledCallback() {
+    return !!scheduledCallback;
+  },
+
+  batchedUpdates: NoopRenderer.batchedUpdates,
+
+  deferredUpdates: NoopRenderer.deferredUpdates,
+
+  unbatchedUpdates: NoopRenderer.unbatchedUpdates,
+
+  flushSync: NoopRenderer.flushSync,
+
+  // Logs the current state of the tree.
+  dumpTree(rootID: string = DEFAULT_ROOT_ID) {
+    const root = roots.get(rootID);
+    const rootContainer = rootContainers.get(rootID);
+    if (!root || !rootContainer) {
+      console.log('Nothing rendered yet.');
+      return;
+    }
+
+    var bufferedLog = [];
+    function log(...args) {
+      bufferedLog.push(...args, '\n');
+    }
+
+    function logHostInstances(children: Array<Instance | TextInstance>, depth) {
+      for (var i = 0; i < children.length; i++) {
+        var child = children[i];
+        var indent = '  '.repeat(depth);
+        if (typeof child.text === 'string') {
+          log(indent + '- ' + child.text);
+        } else {
+          // $FlowFixMe - The child should've been refined now.
+          log(indent + '- ' + child.type + '#' + child.id);
+          // $FlowFixMe - The child should've been refined now.
+          logHostInstances(child.children, depth + 1);
+        }
+      }
+    }
+    function logContainer(container: Container, depth) {
+      log('  '.repeat(depth) + '- [root#' + container.rootID + ']');
+      logHostInstances(container.children, depth + 1);
+    }
+
+    function logUpdateQueue(updateQueue: UpdateQueue, depth) {
+      log('  '.repeat(depth + 1) + 'QUEUED UPDATES');
+      const firstUpdate = updateQueue.first;
+      if (!firstUpdate) {
+        return;
+      }
+
+      log(
+        '  '.repeat(depth + 1) + '~',
+        firstUpdate && firstUpdate.partialState,
+        firstUpdate.callback ? 'with callback' : '',
+        '[' + firstUpdate.priorityLevel + ']',
+      );
+      var next;
+      while ((next = firstUpdate.next)) {
+        log(
+          '  '.repeat(depth + 1) + '~',
+          next.partialState,
+          next.callback ? 'with callback' : '',
+          '[' + firstUpdate.priorityLevel + ']',
+        );
+      }
+    }
+
+    function logFiber(fiber: Fiber, depth) {
+      log(
+        '  '.repeat(depth) +
+          '- ' +
+          (fiber.type ? fiber.type.name || fiber.type : '[root]'),
+        '[' + fiber.pendingWorkPriority + (fiber.pendingProps ? '*' : '') + ']',
+      );
+      if (fiber.updateQueue) {
+        logUpdateQueue(fiber.updateQueue, depth);
+      }
+      // const childInProgress = fiber.progressedChild;
+      // if (childInProgress && childInProgress !== fiber.child) {
+      //   log(
+      //     '  '.repeat(depth + 1) + 'IN PROGRESS: ' + fiber.pendingWorkPriority,
+      //   );
+      //   logFiber(childInProgress, depth + 1);
+      //   if (fiber.child) {
+      //     log('  '.repeat(depth + 1) + 'CURRENT');
+      //   }
+      // } else if (fiber.child && fiber.updateQueue) {
+      //   log('  '.repeat(depth + 1) + 'CHILDREN');
+      // }
+      if (fiber.child) {
+        logFiber(fiber.child, depth + 1);
+      }
+      if (fiber.sibling) {
+        logFiber(fiber.sibling, depth);
+      }
+    }
+
+    log('HOST INSTANCES:');
+    logContainer(rootContainer, 0);
+    log('FIBERS:');
+    logFiber(root.current, 0);
+
+    console.log(...bufferedLog);
+  },
+
+  simulateErrorInHostConfig(fn: () => void) {
+    failInBeginPhase = true;
+    try {
+      fn();
+    } finally {
+      failInBeginPhase = false;
+    }
+  },
+
+};
+
+module.exports = ReactNoop;
diff --git a/fixtures/reconciler/index.js b/fixtures/reconciler/index.js
index 89b1630a89a8c..de072a22bb094 100644
--- a/fixtures/reconciler/index.js
+++ b/fixtures/reconciler/index.js
@@ -1,9 +1,29 @@
-const React = require('react');
-const Reconciler = require('react-reconciler');
-const assert = require('assert');
-const A = Reconciler({});
-const B = Reconciler({});
-
-assert(global.valueStacks.length === 2);
-assert(global.valueStacks[0] !== global.valueStacks[1]);
-console.log('Ok!');
+
+var React = require('react');
+var Noop = require('./NoopRenderer');
+var assert = require('assert');
+
+class Comp extends React.Component {
+  render() {
+    return this.props.active ? 'Active Comp' : 'Deactive Comp';
+  }
+}
+const Children = (props) => props.children;
+const result = Noop.render(
+  <main>
+    <div>Hello</div>
+    <Children>
+      Hello world
+      <span>{'Number '}{42}</span>
+      <Comp active />
+    </Children>
+  </main>
+);
+
+console.log('Noop dumping Tree');
+Noop.dumpTree();
+
+Noop.flushDeferredPri();
+console.log('Noop dumping Tree');
+Noop.dumpTree();
+

From 8f50bf3de16bbbb7804338d11116e46350fa4c3d Mon Sep 17 00:00:00 2001
From: Dustan Kasten <dustan.kasten@gmail.com>
Date: Thu, 28 Sep 2017 09:28:36 -0400
Subject: [PATCH 13/25] Change reconciler fixture test

---
 fixtures/reconciler/index.js | 33 +++++++++++++++++++++++++--------
 1 file changed, 25 insertions(+), 8 deletions(-)

diff --git a/fixtures/reconciler/index.js b/fixtures/reconciler/index.js
index de072a22bb094..36f38d48147ff 100644
--- a/fixtures/reconciler/index.js
+++ b/fixtures/reconciler/index.js
@@ -9,7 +9,7 @@ class Comp extends React.Component {
   }
 }
 const Children = (props) => props.children;
-const result = Noop.render(
+Noop.render(
   <main>
     <div>Hello</div>
     <Children>
@@ -19,11 +19,28 @@ const result = Noop.render(
     </Children>
   </main>
 );
+Noop.flush();
+assert.deepEqual(
+  Noop.getChildren(),
+  [
+    {
+      type: 'main',
+      children: [
+        {type: 'div', children: [], prop: undefined},
+        {text: 'Hello world'},
+        {
+          type: 'span',
+          children: [
+            {text: 'Number '},
+            {text: '42'},
+          ],
+          prop: undefined,
+        },
+        {text: 'Active Comp'}
+      ],
+      prop: undefined,
+    }
+  ]
+);
 
-console.log('Noop dumping Tree');
-Noop.dumpTree();
-
-Noop.flushDeferredPri();
-console.log('Noop dumping Tree');
-Noop.dumpTree();
-
+console.log('Reconciler package is Ok!');

From 8dc59e6d4562d51ab07b8f396cc377c5809c884d Mon Sep 17 00:00:00 2001
From: Dustan Kasten <dustan.kasten@gmail.com>
Date: Thu, 28 Sep 2017 09:47:58 -0400
Subject: [PATCH 14/25] prettier

---
 fixtures/reconciler/NoopRenderer.js | 37 ++++++++++++-----------
 fixtures/reconciler/index.js        | 46 +++++++++++++++--------------
 2 files changed, 43 insertions(+), 40 deletions(-)

diff --git a/fixtures/reconciler/NoopRenderer.js b/fixtures/reconciler/NoopRenderer.js
index 05e766ae30e83..96381ae5cc518 100644
--- a/fixtures/reconciler/NoopRenderer.js
+++ b/fixtures/reconciler/NoopRenderer.js
@@ -45,7 +45,7 @@ var failInBeginPhase = false;
 
 function appendChild(
   parentInstance: Instance | Container,
-  child: Instance | TextInstance,
+  child: Instance | TextInstance
 ): void {
   const index = parentInstance.children.indexOf(child);
   if (index !== -1) {
@@ -57,7 +57,7 @@ function appendChild(
 function insertBefore(
   parentInstance: Instance | Container,
   child: Instance | TextInstance,
-  beforeChild: Instance | TextInstance,
+  beforeChild: Instance | TextInstance
 ): void {
   const index = parentInstance.children.indexOf(child);
   if (index !== -1) {
@@ -72,7 +72,7 @@ function insertBefore(
 
 function removeChild(
   parentInstance: Instance | Container,
-  child: Instance | TextInstance,
+  child: Instance | TextInstance
 ): void {
   const index = parentInstance.children.indexOf(child);
   if (index === -1) {
@@ -111,7 +111,7 @@ var NoopRenderer = ReactFiberReconciler({
 
   appendInitialChild(
     parentInstance: Instance,
-    child: Instance | TextInstance,
+    child: Instance | TextInstance
   ): void {
     parentInstance.children.push(child);
   },
@@ -119,7 +119,7 @@ var NoopRenderer = ReactFiberReconciler({
   finalizeInitialChildren(
     domElement: Instance,
     type: string,
-    props: Props,
+    props: Props
   ): boolean {
     return false;
   },
@@ -128,7 +128,7 @@ var NoopRenderer = ReactFiberReconciler({
     instance: Instance,
     type: string,
     oldProps: Props,
-    newProps: Props,
+    newProps: Props
   ): null | {} {
     return UPDATE_SIGNAL;
   },
@@ -142,7 +142,7 @@ var NoopRenderer = ReactFiberReconciler({
     updatePayload: Object,
     type: string,
     oldProps: Props,
-    newProps: Props,
+    newProps: Props
   ): void {
     instance.prop = newProps.prop;
   },
@@ -163,7 +163,7 @@ var NoopRenderer = ReactFiberReconciler({
     text: string,
     rootContainerInstance: Container,
     hostContext: Object,
-    internalInstanceHandle: Object,
+    internalInstanceHandle: Object
   ): TextInstance {
     var inst = {text: text, id: instanceCounter++};
     // Hide from unit tests
@@ -174,7 +174,7 @@ var NoopRenderer = ReactFiberReconciler({
   commitTextUpdate(
     textInstance: TextInstance,
     oldText: string,
-    newText: string,
+    newText: string
   ): void {
     textInstance.text = newText;
   },
@@ -190,7 +190,7 @@ var NoopRenderer = ReactFiberReconciler({
     if (scheduledCallback) {
       throw new Error(
         'Scheduling a callback twice is excessive. Instead, keep track of ' +
-          'whether the callback has already been scheduled.',
+          'whether the callback has already been scheduled.'
       );
     }
     scheduledCallback = callback;
@@ -253,7 +253,7 @@ var ReactNoop = {
   renderToRootWithID(
     element: React$Element<any>,
     rootID: string,
-    callback: ?Function,
+    callback: ?Function
   ) {
     let root = roots.get(rootID);
     if (!root) {
@@ -310,7 +310,7 @@ var ReactNoop = {
   },
 
   flushAndYield(
-    unitsOfWork: number = Infinity,
+    unitsOfWork: number = Infinity
   ): Generator<Array<mixed>, void, void> {
     return flushUnitsOfWork(unitsOfWork);
   },
@@ -336,8 +336,10 @@ var ReactNoop = {
     assert.deepEqual(
       actual,
       expected,
-      'Unexpected flush results.\nExpected:\n  ' + JSON.stringify(actual, null, 2) +
-      '\n\nActual:\n  ' + JSON.stringify(expected, null, 2)
+      'Unexpected flush results.\nExpected:\n  ' +
+        JSON.stringify(actual, null, 2) +
+        '\n\nActual:\n  ' +
+        JSON.stringify(expected, null, 2)
     );
   },
 
@@ -405,7 +407,7 @@ var ReactNoop = {
         '  '.repeat(depth + 1) + '~',
         firstUpdate && firstUpdate.partialState,
         firstUpdate.callback ? 'with callback' : '',
-        '[' + firstUpdate.priorityLevel + ']',
+        '[' + firstUpdate.priorityLevel + ']'
       );
       var next;
       while ((next = firstUpdate.next)) {
@@ -413,7 +415,7 @@ var ReactNoop = {
           '  '.repeat(depth + 1) + '~',
           next.partialState,
           next.callback ? 'with callback' : '',
-          '[' + firstUpdate.priorityLevel + ']',
+          '[' + firstUpdate.priorityLevel + ']'
         );
       }
     }
@@ -423,7 +425,7 @@ var ReactNoop = {
         '  '.repeat(depth) +
           '- ' +
           (fiber.type ? fiber.type.name || fiber.type : '[root]'),
-        '[' + fiber.pendingWorkPriority + (fiber.pendingProps ? '*' : '') + ']',
+        '[' + fiber.pendingWorkPriority + (fiber.pendingProps ? '*' : '') + ']'
       );
       if (fiber.updateQueue) {
         logUpdateQueue(fiber.updateQueue, depth);
@@ -464,7 +466,6 @@ var ReactNoop = {
       failInBeginPhase = false;
     }
   },
-
 };
 
 module.exports = ReactNoop;
diff --git a/fixtures/reconciler/index.js b/fixtures/reconciler/index.js
index 36f38d48147ff..d290dac0ff62a 100644
--- a/fixtures/reconciler/index.js
+++ b/fixtures/reconciler/index.js
@@ -1,4 +1,3 @@
-
 var React = require('react');
 var Noop = require('./NoopRenderer');
 var assert = require('assert');
@@ -8,7 +7,7 @@ class Comp extends React.Component {
     return this.props.active ? 'Active Comp' : 'Deactive Comp';
   }
 }
-const Children = (props) => props.children;
+const Children = props => props.children;
 Noop.render(
   <main>
     <div>Hello</div>
@@ -20,27 +19,30 @@ Noop.render(
   </main>
 );
 Noop.flush();
+const actual = Noop.getChildren();
+const expected = [
+  {
+    type: 'main',
+    children: [
+      {type: 'div', children: [], prop: undefined},
+      {text: 'Hello world'},
+      {
+        type: 'span',
+        children: [{text: 'Number '}, {text: '42'}],
+        prop: undefined,
+      },
+      {text: 'Active Comp'},
+    ],
+    prop: undefined,
+  },
+];
 assert.deepEqual(
-  Noop.getChildren(),
-  [
-    {
-      type: 'main',
-      children: [
-        {type: 'div', children: [], prop: undefined},
-        {text: 'Hello world'},
-        {
-          type: 'span',
-          children: [
-            {text: 'Number '},
-            {text: '42'},
-          ],
-          prop: undefined,
-        },
-        {text: 'Active Comp'}
-      ],
-      prop: undefined,
-    }
-  ]
+  actual,
+  expected,
+  'Error. Noop.getChildren() returned unexpected value.\nExpected:\  ' +
+    JSON.stringify(expected, null, 2) +
+    '\n\nActual:\n  ' +
+    JSON.stringify(actual, null, 2)
 );
 
 console.log('Reconciler package is Ok!');

From 80f4a6b3015ef89e3ee08dc9f47bbda6f1609f84 Mon Sep 17 00:00:00 2001
From: Dustan Kasten <dustan.kasten@gmail.com>
Date: Thu, 28 Sep 2017 10:04:12 -0400
Subject: [PATCH 15/25] Remove a bunch of Noop test renderer

---
 fixtures/reconciler/NoopRenderer.js | 10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/fixtures/reconciler/NoopRenderer.js b/fixtures/reconciler/NoopRenderer.js
index 96381ae5cc518..d7477bc6fe433 100644
--- a/fixtures/reconciler/NoopRenderer.js
+++ b/fixtures/reconciler/NoopRenderer.js
@@ -1,12 +1,8 @@
 /**
- * Copyright 2013-present, Facebook, Inc.
- * All rights reserved.
+ * Copyright (c) 2015-present, Facebook, Inc.
  *
- * This source code is licensed under the BSD-style license found in the
- * LICENSE file in the root directory of this source tree. An additional grant
- * of patent rights can be found in the PATENTS file in the same directory.
- *
- * @flow
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
  */
 
 /**

From 9d5345d707a1f0b6a17c7cffc556158571fbf395 Mon Sep 17 00:00:00 2001
From: Dustan Kasten <dustan.kasten@gmail.com>
Date: Thu, 28 Sep 2017 10:09:15 -0400
Subject: [PATCH 16/25] =?UTF-8?q?Delete=20a=20bunch=20of=20stuff=20we=20do?=
 =?UTF-8?q?n=E2=80=99t=20care=20about=20for=20reconciler=20teesting.=20Add?=
 =?UTF-8?q?=20flow=20pragmas=20for=20future=20flow=20pragma=20testing?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 fixtures/reconciler/NoopRenderer.js | 193 +---------------------------
 fixtures/reconciler/index.js        |   3 +
 2 files changed, 6 insertions(+), 190 deletions(-)

diff --git a/fixtures/reconciler/NoopRenderer.js b/fixtures/reconciler/NoopRenderer.js
index d7477bc6fe433..11110a7023ba3 100644
--- a/fixtures/reconciler/NoopRenderer.js
+++ b/fixtures/reconciler/NoopRenderer.js
@@ -1,24 +1,14 @@
-/**
- * Copyright (c) 2015-present, Facebook, Inc.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
-
 /**
  * This is a renderer of React that doesn't have a render target output.
- * It is useful to demonstrate the internals of the reconciler in isolation
- * and for testing semantics of reconciliation separate from the host
- * environment.
+ * It is used to test that the react-reconciler package doesn't blow up.
+ *
+ * @flow
  */
 
 'use strict';
 
-import type {Fiber} from 'ReactFiber';
-import type {UpdateQueue} from 'ReactFiberUpdateQueue';
 var ReactFiberReconciler = require('react-reconciler');
 var emptyObject = require('fbjs/lib/emptyObject');
-
 var assert = require('assert');
 
 const UPDATE_SIGNAL = {};
@@ -37,8 +27,6 @@ type TextInstance = {|text: string, id: number|};
 
 var instanceCounter = 0;
 
-var failInBeginPhase = false;
-
 function appendChild(
   parentInstance: Instance | Container,
   child: Instance | TextInstance
@@ -79,9 +67,6 @@ function removeChild(
 
 var NoopRenderer = ReactFiberReconciler({
   getRootHostContext() {
-    if (failInBeginPhase) {
-      throw new Error('Error in host config.');
-    }
     return emptyObject;
   },
 
@@ -271,46 +256,10 @@ var ReactNoop = {
     }
   },
 
-  /* We don’t have access to ReactInstanceMap from the outside
-  findInstance(
-    componentOrElement: Element | ?React$Component<any, any>,
-  ): null | Instance | TextInstance {
-    if (componentOrElement == null) {
-      return null;
-    }
-    // Unsound duck typing.
-    const component = (componentOrElement: any);
-    if (typeof component.id === 'number') {
-      return component;
-    }
-    const inst = ReactInstanceMap.get(component);
-    return inst ? NoopRenderer.findHostInstance(inst) : null;
-  },
-  */
-
-  flushDeferredPri(timeout: number = Infinity): Array<mixed> {
-    // The legacy version of this function decremented the timeout before
-    // returning the new time.
-    // TODO: Convert tests to use flushUnitsOfWork or flushAndYield instead.
-    const n = timeout / 5 - 1;
-
-    let values = [];
-    for (const value of flushUnitsOfWork(n)) {
-      values.push(...value);
-    }
-    return values;
-  },
-
   flush(): Array<mixed> {
     return ReactNoop.flushUnitsOfWork(Infinity);
   },
 
-  flushAndYield(
-    unitsOfWork: number = Infinity
-  ): Generator<Array<mixed>, void, void> {
-    return flushUnitsOfWork(unitsOfWork);
-  },
-
   flushUnitsOfWork(n: number): Array<mixed> {
     let values = [];
     for (const value of flushUnitsOfWork(n)) {
@@ -319,38 +268,6 @@ var ReactNoop = {
     return values;
   },
 
-  flushThrough(expected: Array<mixed>): void {
-    let actual = [];
-    if (expected.length !== 0) {
-      for (const value of flushUnitsOfWork(Infinity)) {
-        actual.push(...value);
-        if (actual.length >= expected.length) {
-          break;
-        }
-      }
-    }
-    assert.deepEqual(
-      actual,
-      expected,
-      'Unexpected flush results.\nExpected:\n  ' +
-        JSON.stringify(actual, null, 2) +
-        '\n\nActual:\n  ' +
-        JSON.stringify(expected, null, 2)
-    );
-  },
-
-  yield(value: mixed) {
-    if (yieldedValues === null) {
-      yieldedValues = [value];
-    } else {
-      yieldedValues.push(value);
-    }
-  },
-
-  hasScheduledCallback() {
-    return !!scheduledCallback;
-  },
-
   batchedUpdates: NoopRenderer.batchedUpdates,
 
   deferredUpdates: NoopRenderer.deferredUpdates,
@@ -358,110 +275,6 @@ var ReactNoop = {
   unbatchedUpdates: NoopRenderer.unbatchedUpdates,
 
   flushSync: NoopRenderer.flushSync,
-
-  // Logs the current state of the tree.
-  dumpTree(rootID: string = DEFAULT_ROOT_ID) {
-    const root = roots.get(rootID);
-    const rootContainer = rootContainers.get(rootID);
-    if (!root || !rootContainer) {
-      console.log('Nothing rendered yet.');
-      return;
-    }
-
-    var bufferedLog = [];
-    function log(...args) {
-      bufferedLog.push(...args, '\n');
-    }
-
-    function logHostInstances(children: Array<Instance | TextInstance>, depth) {
-      for (var i = 0; i < children.length; i++) {
-        var child = children[i];
-        var indent = '  '.repeat(depth);
-        if (typeof child.text === 'string') {
-          log(indent + '- ' + child.text);
-        } else {
-          // $FlowFixMe - The child should've been refined now.
-          log(indent + '- ' + child.type + '#' + child.id);
-          // $FlowFixMe - The child should've been refined now.
-          logHostInstances(child.children, depth + 1);
-        }
-      }
-    }
-    function logContainer(container: Container, depth) {
-      log('  '.repeat(depth) + '- [root#' + container.rootID + ']');
-      logHostInstances(container.children, depth + 1);
-    }
-
-    function logUpdateQueue(updateQueue: UpdateQueue, depth) {
-      log('  '.repeat(depth + 1) + 'QUEUED UPDATES');
-      const firstUpdate = updateQueue.first;
-      if (!firstUpdate) {
-        return;
-      }
-
-      log(
-        '  '.repeat(depth + 1) + '~',
-        firstUpdate && firstUpdate.partialState,
-        firstUpdate.callback ? 'with callback' : '',
-        '[' + firstUpdate.priorityLevel + ']'
-      );
-      var next;
-      while ((next = firstUpdate.next)) {
-        log(
-          '  '.repeat(depth + 1) + '~',
-          next.partialState,
-          next.callback ? 'with callback' : '',
-          '[' + firstUpdate.priorityLevel + ']'
-        );
-      }
-    }
-
-    function logFiber(fiber: Fiber, depth) {
-      log(
-        '  '.repeat(depth) +
-          '- ' +
-          (fiber.type ? fiber.type.name || fiber.type : '[root]'),
-        '[' + fiber.pendingWorkPriority + (fiber.pendingProps ? '*' : '') + ']'
-      );
-      if (fiber.updateQueue) {
-        logUpdateQueue(fiber.updateQueue, depth);
-      }
-      // const childInProgress = fiber.progressedChild;
-      // if (childInProgress && childInProgress !== fiber.child) {
-      //   log(
-      //     '  '.repeat(depth + 1) + 'IN PROGRESS: ' + fiber.pendingWorkPriority,
-      //   );
-      //   logFiber(childInProgress, depth + 1);
-      //   if (fiber.child) {
-      //     log('  '.repeat(depth + 1) + 'CURRENT');
-      //   }
-      // } else if (fiber.child && fiber.updateQueue) {
-      //   log('  '.repeat(depth + 1) + 'CHILDREN');
-      // }
-      if (fiber.child) {
-        logFiber(fiber.child, depth + 1);
-      }
-      if (fiber.sibling) {
-        logFiber(fiber.sibling, depth);
-      }
-    }
-
-    log('HOST INSTANCES:');
-    logContainer(rootContainer, 0);
-    log('FIBERS:');
-    logFiber(root.current, 0);
-
-    console.log(...bufferedLog);
-  },
-
-  simulateErrorInHostConfig(fn: () => void) {
-    failInBeginPhase = true;
-    try {
-      fn();
-    } finally {
-      failInBeginPhase = false;
-    }
-  },
 };
 
 module.exports = ReactNoop;
diff --git a/fixtures/reconciler/index.js b/fixtures/reconciler/index.js
index d290dac0ff62a..6be1296c3d85b 100644
--- a/fixtures/reconciler/index.js
+++ b/fixtures/reconciler/index.js
@@ -1,3 +1,6 @@
+/**
+ * @flow
+ */
 var React = require('react');
 var Noop = require('./NoopRenderer');
 var assert = require('assert');

From 6de269f0cd64be1164cd0258deb20082cfe61e03 Mon Sep 17 00:00:00 2001
From: Dan Abramov <dan.abramov@gmail.com>
Date: Tue, 10 Oct 2017 19:11:36 +0100
Subject: [PATCH 17/25] Remove PATENTS

---
 packages/react-reconciler/package.json | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/packages/react-reconciler/package.json b/packages/react-reconciler/package.json
index 0019bb3748b2f..0a5ef163007eb 100644
--- a/packages/react-reconciler/package.json
+++ b/packages/react-reconciler/package.json
@@ -1,16 +1,15 @@
 {
   "name": "react-reconciler",
-  "description": "React package for creating custom reconcilers.",
+  "description": "React package for creating custom renderers.",
   "version": "0.1.0",
   "keywords": [
     "react"
   ],
   "homepage": "https://facebook.github.io/react/",
   "bugs": "https://github.com/facebook/react/issues",
-  "license": "BSD-3-Clause",
+  "license": "MIT",
   "files": [
     "LICENSE",
-    "PATENTS",
     "README.md",
     "index.js",
     "cjs/",
@@ -22,13 +21,13 @@
     "node": ">=0.10.0"
   },
   "peerDependencies": {
-    "react": "^16.0.0-beta.3"
+    "react": "^16.0.0"
   },
   "dependencies": {
-    "fbjs": "^0.8.9",
+    "fbjs": "^0.8.16",
     "loose-envify": "^1.1.0",
-    "object-assign": "^4.1.0",
-    "prop-types": "^15.5.6"
+    "object-assign": "^4.1.1",
+    "prop-types": "^15.6.0"
   },
   "browserify": {
     "transform": [

From f767f0ef5df513b5baae7058e018b5f8d02ca3a0 Mon Sep 17 00:00:00 2001
From: Dustan Kasten <dustan.kasten@gmail.com>
Date: Wed, 11 Oct 2017 09:12:12 -0400
Subject: [PATCH 18/25] Update Reconciler fixture docs

---
 fixtures/reconciler/README.md    | 25 ++++++++++-----------
 fixtures/reconciler/package.json |  2 +-
 fixtures/reconciler/yarn.lock    | 37 ++++++++++++++++----------------
 3 files changed, 33 insertions(+), 31 deletions(-)

diff --git a/fixtures/reconciler/README.md b/fixtures/reconciler/README.md
index 6798d09f5f248..ba35e043fd8ba 100644
--- a/fixtures/reconciler/README.md
+++ b/fixtures/reconciler/README.md
@@ -1,16 +1,17 @@
+# React Reconciler Test Fixture
 
-To test, run:
-* `yarn install` 
-* edit node_modules/react-reconciler/cjs/react-reconciler.development.js 
-* Add the below snipper after `var valueStack = [];`
-* `yarn test`
+This folder exists for **React contributors** only.
+If you use React you don't need to worry about it.
 
-If everything is okay then you should see `Ok!` printed to the console.
+These fixtures are a smoke-screen verification that the built React Reconciler distributions do not
+share internal global  state.
+**They are not running automatically.** (At least not yet, feel free to contribute to automate them.)
+
+Run them when you make changes to how we package React or perform any release.
 
+To test, from the project root:
+* `yarn build`
+* `pushd fixtures/reconciler; yarn install && yarn test; popd`
+
+If everything is okay then you should see `Ok!` printed to the console.
 
-```
-if (global.valueStacks === undefined) {
-  global.valueStacks = [];
-}
-global.valueStacks.push(valueStack);
-```
diff --git a/fixtures/reconciler/package.json b/fixtures/reconciler/package.json
index a288c1e22963b..abe75ffad2dba 100644
--- a/fixtures/reconciler/package.json
+++ b/fixtures/reconciler/package.json
@@ -3,7 +3,7 @@
   "version": "0.1.0",
   "private": true,
   "dependencies": {
-    "react": "^16.0.0-",
+    "react": "^16.0.0",
     "react-reconciler": "file:../../build/packages/react-reconciler"
   },
   "scripts": {
diff --git a/fixtures/reconciler/yarn.lock b/fixtures/reconciler/yarn.lock
index 64bb62652dcfa..b843eb76e551f 100644
--- a/fixtures/reconciler/yarn.lock
+++ b/fixtures/reconciler/yarn.lock
@@ -16,9 +16,9 @@ encoding@^0.1.11:
   dependencies:
     iconv-lite "~0.4.13"
 
-fbjs@^0.8.9:
-  version "0.8.15"
-  resolved "https://registry.yarnpkg.com/fbjs/-/fbjs-0.8.15.tgz#4f0695fdfcc16c37c0b07facec8cb4c4091685b9"
+fbjs@^0.8.16:
+  version "0.8.16"
+  resolved "https://registry.yarnpkg.com/fbjs/-/fbjs-0.8.16.tgz#5e67432f550dc41b572bf55847b8aca64e5337db"
   dependencies:
     core-js "^1.0.0"
     isomorphic-fetch "^2.1.1"
@@ -60,7 +60,7 @@ node-fetch@^1.0.1:
     encoding "^0.1.11"
     is-stream "^1.0.1"
 
-object-assign@^4.1.0:
+object-assign@^4.1.0, object-assign@^4.1.1:
   version "4.1.1"
   resolved "https://registry.yarnpkg.com/object-assign/-/object-assign-4.1.1.tgz#2109adc7965887cfc05cbbd442cac8bfbb360863"
 
@@ -70,29 +70,30 @@ promise@^7.1.1:
   dependencies:
     asap "~2.0.3"
 
-prop-types@^15.5.6:
-  version "15.5.10"
-  resolved "https://registry.yarnpkg.com/prop-types/-/prop-types-15.5.10.tgz#2797dfc3126182e3a95e3dfbb2e893ddd7456154"
+prop-types@^15.6.0:
+  version "15.6.0"
+  resolved "https://registry.yarnpkg.com/prop-types/-/prop-types-15.6.0.tgz#ceaf083022fc46b4a35f69e13ef75aed0d639856"
   dependencies:
-    fbjs "^0.8.9"
+    fbjs "^0.8.16"
     loose-envify "^1.3.1"
+    object-assign "^4.1.1"
 
 "react-reconciler@file:../../build/packages/react-reconciler":
-  version "16.0.0"
+  version "0.1.0"
   dependencies:
-    fbjs "^0.8.9"
+    fbjs "^0.8.16"
     loose-envify "^1.1.0"
-    object-assign "^4.1.0"
-    prop-types "^15.5.6"
+    object-assign "^4.1.1"
+    prop-types "^15.6.0"
 
-react@^16.0.0-:
-  version "16.0.0-rc.3"
-  resolved "https://registry.yarnpkg.com/react/-/react-16.0.0-rc.3.tgz#4a9df996326ba7185903d9fbed3149765e237e26"
+react@^16.0.0:
+  version "16.0.0"
+  resolved "https://registry.yarnpkg.com/react/-/react-16.0.0.tgz#ce7df8f1941b036f02b2cca9dbd0cb1f0e855e2d"
   dependencies:
-    fbjs "^0.8.9"
+    fbjs "^0.8.16"
     loose-envify "^1.1.0"
-    object-assign "^4.1.0"
-    prop-types "^15.5.6"
+    object-assign "^4.1.1"
+    prop-types "^15.6.0"
 
 setimmediate@^1.0.5:
   version "1.0.5"

From d4842f075061081b0d97e65ffb5336b25277e774 Mon Sep 17 00:00:00 2001
From: Dustan Kasten <dustan.kasten@gmail.com>
Date: Wed, 11 Oct 2017 09:47:33 -0400
Subject: [PATCH 19/25] ReactDOMUnstableNativeDependencies should be ISOMORPHIC

---
 scripts/rollup/bundles.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/rollup/bundles.js b/scripts/rollup/bundles.js
index 6ba9f3dd4aee2..ef4c229fd1862 100644
--- a/scripts/rollup/bundles.js
+++ b/scripts/rollup/bundles.js
@@ -157,7 +157,7 @@ const bundles = [
     ],
     fbEntry: 'src/renderers/dom/shared/ReactDOMUnstableNativeDependenciesEntry',
     hasteName: 'ReactDOMUnstableNativeDependencies',
-    moduleType: RENDERER,
+    moduleType: ISOMORPHIC,
     label: 'dom-unstable-native-dependencies',
     manglePropertiesOnProd: false,
     name: 'react-dom/unstable-native-dependencies',

From d10506bc9053750142292a4d9098f38d215bb1ee Mon Sep 17 00:00:00 2001
From: Dustan Kasten <dustan.kasten@gmail.com>
Date: Wed, 11 Oct 2017 10:10:35 -0400
Subject: [PATCH 20/25] Inline fixture renderer

---
 fixtures/reconciler/NoopRenderer.js | 280 ----------------------------
 fixtures/reconciler/README.md       |   3 +-
 fixtures/reconciler/index.js        | 277 ++++++++++++++++++++++++++-
 3 files changed, 277 insertions(+), 283 deletions(-)
 delete mode 100644 fixtures/reconciler/NoopRenderer.js

diff --git a/fixtures/reconciler/NoopRenderer.js b/fixtures/reconciler/NoopRenderer.js
deleted file mode 100644
index 11110a7023ba3..0000000000000
--- a/fixtures/reconciler/NoopRenderer.js
+++ /dev/null
@@ -1,280 +0,0 @@
-/**
- * This is a renderer of React that doesn't have a render target output.
- * It is used to test that the react-reconciler package doesn't blow up.
- *
- * @flow
- */
-
-'use strict';
-
-var ReactFiberReconciler = require('react-reconciler');
-var emptyObject = require('fbjs/lib/emptyObject');
-var assert = require('assert');
-
-const UPDATE_SIGNAL = {};
-
-var scheduledCallback = null;
-
-type Container = {rootID: string, children: Array<Instance | TextInstance>};
-type Props = {prop: any, hidden?: boolean};
-type Instance = {|
-  type: string,
-  id: number,
-  children: Array<Instance | TextInstance>,
-  prop: any,
-|};
-type TextInstance = {|text: string, id: number|};
-
-var instanceCounter = 0;
-
-function appendChild(
-  parentInstance: Instance | Container,
-  child: Instance | TextInstance
-): void {
-  const index = parentInstance.children.indexOf(child);
-  if (index !== -1) {
-    parentInstance.children.splice(index, 1);
-  }
-  parentInstance.children.push(child);
-}
-
-function insertBefore(
-  parentInstance: Instance | Container,
-  child: Instance | TextInstance,
-  beforeChild: Instance | TextInstance
-): void {
-  const index = parentInstance.children.indexOf(child);
-  if (index !== -1) {
-    parentInstance.children.splice(index, 1);
-  }
-  const beforeIndex = parentInstance.children.indexOf(beforeChild);
-  if (beforeIndex === -1) {
-    throw new Error('This child does not exist.');
-  }
-  parentInstance.children.splice(beforeIndex, 0, child);
-}
-
-function removeChild(
-  parentInstance: Instance | Container,
-  child: Instance | TextInstance
-): void {
-  const index = parentInstance.children.indexOf(child);
-  if (index === -1) {
-    throw new Error('This child does not exist.');
-  }
-  parentInstance.children.splice(index, 1);
-}
-
-var NoopRenderer = ReactFiberReconciler({
-  getRootHostContext() {
-    return emptyObject;
-  },
-
-  getChildHostContext() {
-    return emptyObject;
-  },
-
-  getPublicInstance(instance) {
-    return instance;
-  },
-
-  createInstance(type: string, props: Props): Instance {
-    const inst = {
-      id: instanceCounter++,
-      type: type,
-      children: [],
-      prop: props.prop,
-    };
-    // Hide from unit tests
-    Object.defineProperty(inst, 'id', {value: inst.id, enumerable: false});
-    return inst;
-  },
-
-  appendInitialChild(
-    parentInstance: Instance,
-    child: Instance | TextInstance
-  ): void {
-    parentInstance.children.push(child);
-  },
-
-  finalizeInitialChildren(
-    domElement: Instance,
-    type: string,
-    props: Props
-  ): boolean {
-    return false;
-  },
-
-  prepareUpdate(
-    instance: Instance,
-    type: string,
-    oldProps: Props,
-    newProps: Props
-  ): null | {} {
-    return UPDATE_SIGNAL;
-  },
-
-  commitMount(instance: Instance, type: string, newProps: Props): void {
-    // Noop
-  },
-
-  commitUpdate(
-    instance: Instance,
-    updatePayload: Object,
-    type: string,
-    oldProps: Props,
-    newProps: Props
-  ): void {
-    instance.prop = newProps.prop;
-  },
-
-  shouldSetTextContent(type: string, props: Props): boolean {
-    return (
-      typeof props.children === 'string' || typeof props.children === 'number'
-    );
-  },
-
-  resetTextContent(instance: Instance): void {},
-
-  shouldDeprioritizeSubtree(type: string, props: Props): boolean {
-    return !!props.hidden;
-  },
-
-  createTextInstance(
-    text: string,
-    rootContainerInstance: Container,
-    hostContext: Object,
-    internalInstanceHandle: Object
-  ): TextInstance {
-    var inst = {text: text, id: instanceCounter++};
-    // Hide from unit tests
-    Object.defineProperty(inst, 'id', {value: inst.id, enumerable: false});
-    return inst;
-  },
-
-  commitTextUpdate(
-    textInstance: TextInstance,
-    oldText: string,
-    newText: string
-  ): void {
-    textInstance.text = newText;
-  },
-
-  appendChild: appendChild,
-  appendChildToContainer: appendChild,
-  insertBefore: insertBefore,
-  insertInContainerBefore: insertBefore,
-  removeChild: removeChild,
-  removeChildFromContainer: removeChild,
-
-  scheduleDeferredCallback(callback) {
-    if (scheduledCallback) {
-      throw new Error(
-        'Scheduling a callback twice is excessive. Instead, keep track of ' +
-          'whether the callback has already been scheduled.'
-      );
-    }
-    scheduledCallback = callback;
-  },
-
-  prepareForCommit(): void {},
-
-  resetAfterCommit(): void {},
-});
-
-var rootContainers = new Map();
-var roots = new Map();
-var DEFAULT_ROOT_ID = '<default>';
-
-let yieldedValues = null;
-
-function* flushUnitsOfWork(n: number): Generator<Array<mixed>, void, void> {
-  var didStop = false;
-  while (!didStop && scheduledCallback !== null) {
-    var cb = scheduledCallback;
-    scheduledCallback = null;
-    yieldedValues = null;
-    var unitsRemaining = n;
-    cb({
-      timeRemaining() {
-        if (yieldedValues !== null) {
-          return 0;
-        }
-        if (unitsRemaining-- > 0) {
-          return 999;
-        }
-        didStop = true;
-        return 0;
-      },
-    });
-
-    if (yieldedValues !== null) {
-      const values = yieldedValues;
-      yieldedValues = null;
-      yield values;
-    }
-  }
-}
-
-var ReactNoop = {
-  getChildren(rootID: string = DEFAULT_ROOT_ID) {
-    const container = rootContainers.get(rootID);
-    if (container) {
-      return container.children;
-    } else {
-      return null;
-    }
-  },
-
-  // Shortcut for testing a single root
-  render(element: React$Element<any>, callback: ?Function) {
-    ReactNoop.renderToRootWithID(element, DEFAULT_ROOT_ID, callback);
-  },
-
-  renderToRootWithID(
-    element: React$Element<any>,
-    rootID: string,
-    callback: ?Function
-  ) {
-    let root = roots.get(rootID);
-    if (!root) {
-      const container = {rootID: rootID, children: []};
-      rootContainers.set(rootID, container);
-      root = NoopRenderer.createContainer(container);
-      roots.set(rootID, root);
-    }
-    NoopRenderer.updateContainer(element, root, null, callback);
-  },
-
-  unmountRootWithID(rootID: string) {
-    const root = roots.get(rootID);
-    if (root) {
-      NoopRenderer.updateContainer(null, root, null, () => {
-        roots.delete(rootID);
-        rootContainers.delete(rootID);
-      });
-    }
-  },
-
-  flush(): Array<mixed> {
-    return ReactNoop.flushUnitsOfWork(Infinity);
-  },
-
-  flushUnitsOfWork(n: number): Array<mixed> {
-    let values = [];
-    for (const value of flushUnitsOfWork(n)) {
-      values.push(...value);
-    }
-    return values;
-  },
-
-  batchedUpdates: NoopRenderer.batchedUpdates,
-
-  deferredUpdates: NoopRenderer.deferredUpdates,
-
-  unbatchedUpdates: NoopRenderer.unbatchedUpdates,
-
-  flushSync: NoopRenderer.flushSync,
-};
-
-module.exports = ReactNoop;
diff --git a/fixtures/reconciler/README.md b/fixtures/reconciler/README.md
index ba35e043fd8ba..1b00e827094d5 100644
--- a/fixtures/reconciler/README.md
+++ b/fixtures/reconciler/README.md
@@ -3,8 +3,7 @@
 This folder exists for **React contributors** only.
 If you use React you don't need to worry about it.
 
-These fixtures are a smoke-screen verification that the built React Reconciler distributions do not
-share internal global  state.
+These fixtures are a smoke-screen verification that the built React Reconciler distribution works.
 **They are not running automatically.** (At least not yet, feel free to contribute to automate them.)
 
 Run them when you make changes to how we package React or perform any release.
diff --git a/fixtures/reconciler/index.js b/fixtures/reconciler/index.js
index 6be1296c3d85b..248ff0e073d52 100644
--- a/fixtures/reconciler/index.js
+++ b/fixtures/reconciler/index.js
@@ -1,9 +1,284 @@
 /**
+ * This is a renderer of React that doesn't have a render target output.
+ * It is used to test that the react-reconciler package doesn't blow up.
+ *
  * @flow
  */
+'use strict';
+
 var React = require('react');
-var Noop = require('./NoopRenderer');
 var assert = require('assert');
+var ReactFiberReconciler = require('react-reconciler');
+var emptyObject = require('fbjs/lib/emptyObject');
+var assert = require('assert');
+
+const UPDATE_SIGNAL = {};
+
+var scheduledCallback = null;
+
+type Container = {rootID: string, children: Array<Instance | TextInstance>};
+type Props = {prop: any, hidden?: boolean};
+type Instance = {|
+  type: string,
+  id: number,
+  children: Array<Instance | TextInstance>,
+  prop: any,
+|};
+type TextInstance = {|text: string, id: number|};
+
+var instanceCounter = 0;
+
+function appendChild(
+  parentInstance: Instance | Container,
+  child: Instance | TextInstance
+): void {
+  const index = parentInstance.children.indexOf(child);
+  if (index !== -1) {
+    parentInstance.children.splice(index, 1);
+  }
+  parentInstance.children.push(child);
+}
+
+function insertBefore(
+  parentInstance: Instance | Container,
+  child: Instance | TextInstance,
+  beforeChild: Instance | TextInstance
+): void {
+  const index = parentInstance.children.indexOf(child);
+  if (index !== -1) {
+    parentInstance.children.splice(index, 1);
+  }
+  const beforeIndex = parentInstance.children.indexOf(beforeChild);
+  if (beforeIndex === -1) {
+    throw new Error('This child does not exist.');
+  }
+  parentInstance.children.splice(beforeIndex, 0, child);
+}
+
+function removeChild(
+  parentInstance: Instance | Container,
+  child: Instance | TextInstance
+): void {
+  const index = parentInstance.children.indexOf(child);
+  if (index === -1) {
+    throw new Error('This child does not exist.');
+  }
+  parentInstance.children.splice(index, 1);
+}
+
+var NoopRenderer = ReactFiberReconciler({
+  getRootHostContext() {
+    return emptyObject;
+  },
+
+  getChildHostContext() {
+    return emptyObject;
+  },
+
+  getPublicInstance(instance) {
+    return instance;
+  },
+
+  createInstance(type: string, props: Props): Instance {
+    const inst = {
+      id: instanceCounter++,
+      type: type,
+      children: [],
+      prop: props.prop,
+    };
+    // Hide from unit tests
+    Object.defineProperty(inst, 'id', {value: inst.id, enumerable: false});
+    return inst;
+  },
+
+  appendInitialChild(
+    parentInstance: Instance,
+    child: Instance | TextInstance
+  ): void {
+    parentInstance.children.push(child);
+  },
+
+  finalizeInitialChildren(
+    domElement: Instance,
+    type: string,
+    props: Props
+  ): boolean {
+    return false;
+  },
+
+  prepareUpdate(
+    instance: Instance,
+    type: string,
+    oldProps: Props,
+    newProps: Props
+  ): null | {} {
+    return UPDATE_SIGNAL;
+  },
+
+  commitMount(instance: Instance, type: string, newProps: Props): void {
+    // Noop
+  },
+
+  commitUpdate(
+    instance: Instance,
+    updatePayload: Object,
+    type: string,
+    oldProps: Props,
+    newProps: Props
+  ): void {
+    instance.prop = newProps.prop;
+  },
+
+  shouldSetTextContent(type: string, props: Props): boolean {
+    return (
+      typeof props.children === 'string' || typeof props.children === 'number'
+    );
+  },
+
+  resetTextContent(instance: Instance): void {},
+
+  shouldDeprioritizeSubtree(type: string, props: Props): boolean {
+    return !!props.hidden;
+  },
+
+  now: Date.now,
+
+  createTextInstance(
+    text: string,
+    rootContainerInstance: Container,
+    hostContext: Object,
+    internalInstanceHandle: Object
+  ): TextInstance {
+    var inst = {text: text, id: instanceCounter++};
+    // Hide from unit tests
+    Object.defineProperty(inst, 'id', {value: inst.id, enumerable: false});
+    return inst;
+  },
+
+  commitTextUpdate(
+    textInstance: TextInstance,
+    oldText: string,
+    newText: string
+  ): void {
+    textInstance.text = newText;
+  },
+
+  appendChild: appendChild,
+  appendChildToContainer: appendChild,
+  insertBefore: insertBefore,
+  insertInContainerBefore: insertBefore,
+  removeChild: removeChild,
+  removeChildFromContainer: removeChild,
+
+  scheduleDeferredCallback(callback) {
+    if (scheduledCallback) {
+      throw new Error(
+        'Scheduling a callback twice is excessive. Instead, keep track of ' +
+          'whether the callback has already been scheduled.'
+      );
+    }
+    scheduledCallback = callback;
+  },
+
+  prepareForCommit(): void {},
+
+  resetAfterCommit(): void {},
+});
+
+var rootContainers = new Map();
+var roots = new Map();
+var DEFAULT_ROOT_ID = '<default>';
+
+let yieldedValues = null;
+
+function* flushUnitsOfWork(n: number): Generator<Array<mixed>, void, void> {
+  var didStop = false;
+  while (!didStop && scheduledCallback !== null) {
+    var cb = scheduledCallback;
+    scheduledCallback = null;
+    yieldedValues = null;
+    var unitsRemaining = n;
+    cb({
+      timeRemaining() {
+        if (yieldedValues !== null) {
+          return 0;
+        }
+        if (unitsRemaining-- > 0) {
+          return 999;
+        }
+        didStop = true;
+        return 0;
+      },
+    });
+
+    if (yieldedValues !== null) {
+      const values = yieldedValues;
+      yieldedValues = null;
+      yield values;
+    }
+  }
+}
+
+var Noop = {
+  getChildren(rootID: string = DEFAULT_ROOT_ID) {
+    const container = rootContainers.get(rootID);
+    if (container) {
+      return container.children;
+    } else {
+      return null;
+    }
+  },
+
+  // Shortcut for testing a single root
+  render(element: React$Element<any>, callback: ?Function) {
+    Noop.renderToRootWithID(element, DEFAULT_ROOT_ID, callback);
+  },
+
+  renderToRootWithID(
+    element: React$Element<any>,
+    rootID: string,
+    callback: ?Function
+  ) {
+    let root = roots.get(rootID);
+    if (!root) {
+      const container = {rootID: rootID, children: []};
+      rootContainers.set(rootID, container);
+      root = NoopRenderer.createContainer(container);
+      roots.set(rootID, root);
+    }
+    NoopRenderer.updateContainer(element, root, null, callback);
+  },
+
+  unmountRootWithID(rootID: string) {
+    const root = roots.get(rootID);
+    if (root) {
+      NoopRenderer.updateContainer(null, root, null, () => {
+        roots.delete(rootID);
+        rootContainers.delete(rootID);
+      });
+    }
+  },
+
+  flush(): Array<mixed> {
+    return Noop.flushUnitsOfWork(Infinity);
+  },
+
+  flushUnitsOfWork(n: number): Array<mixed> {
+    let values = [];
+    for (const value of flushUnitsOfWork(n)) {
+      values.push(...value);
+    }
+    return values;
+  },
+
+  batchedUpdates: NoopRenderer.batchedUpdates,
+
+  deferredUpdates: NoopRenderer.deferredUpdates,
+
+  unbatchedUpdates: NoopRenderer.unbatchedUpdates,
+
+  flushSync: NoopRenderer.flushSync,
+};
 
 class Comp extends React.Component {
   render() {

From ec188633a0dc9cf9b87e871301fe479fd6e12997 Mon Sep 17 00:00:00 2001
From: Dan Abramov <dan.abramov@gmail.com>
Date: Wed, 11 Oct 2017 16:30:37 +0100
Subject: [PATCH 21/25] Make it "RENDERER"

---
 scripts/rollup/bundles.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/rollup/bundles.js b/scripts/rollup/bundles.js
index ef4c229fd1862..6ba9f3dd4aee2 100644
--- a/scripts/rollup/bundles.js
+++ b/scripts/rollup/bundles.js
@@ -157,7 +157,7 @@ const bundles = [
     ],
     fbEntry: 'src/renderers/dom/shared/ReactDOMUnstableNativeDependenciesEntry',
     hasteName: 'ReactDOMUnstableNativeDependencies',
-    moduleType: ISOMORPHIC,
+    moduleType: RENDERER,
     label: 'dom-unstable-native-dependencies',
     manglePropertiesOnProd: false,
     name: 'react-dom/unstable-native-dependencies',

From 5c6510d9767238c928b3c3d3d427b1c061de8d0f Mon Sep 17 00:00:00 2001
From: Dan Abramov <dan.abramov@gmail.com>
Date: Wed, 11 Oct 2017 17:16:11 +0100
Subject: [PATCH 22/25] There is no UMD build. It also doesn't need propTypes.

---
 packages/react-reconciler/package.json | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/packages/react-reconciler/package.json b/packages/react-reconciler/package.json
index 0a5ef163007eb..1432bb2ee6871 100644
--- a/packages/react-reconciler/package.json
+++ b/packages/react-reconciler/package.json
@@ -12,8 +12,7 @@
     "LICENSE",
     "README.md",
     "index.js",
-    "cjs/",
-    "umd/"
+    "cjs/"
   ],
   "main": "index.js",
   "repository": "facebook/react",
@@ -26,8 +25,7 @@
   "dependencies": {
     "fbjs": "^0.8.16",
     "loose-envify": "^1.1.0",
-    "object-assign": "^4.1.1",
-    "prop-types": "^15.6.0"
+    "object-assign": "^4.1.1"
   },
   "browserify": {
     "transform": [

From 8a3ffdce69906b587a8272924d1b3dee56de33f9 Mon Sep 17 00:00:00 2001
From: Dan Abramov <dan.abramov@gmail.com>
Date: Wed, 11 Oct 2017 18:49:16 +0100
Subject: [PATCH 23/25] Tweak how the reconciler is built

---
 fixtures/reconciler/README.md    |   9 +--
 fixtures/reconciler/index.js     |  82 +++++++++++++++++------
 fixtures/reconciler/package.json |   9 +--
 fixtures/reconciler/yarn.lock    | 108 -------------------------------
 scripts/circleci/build.sh        |   6 +-
 scripts/rollup/build.js          |  64 ++++++++++++++----
 6 files changed, 123 insertions(+), 155 deletions(-)
 delete mode 100644 fixtures/reconciler/yarn.lock

diff --git a/fixtures/reconciler/README.md b/fixtures/reconciler/README.md
index 1b00e827094d5..0fbec76424ac0 100644
--- a/fixtures/reconciler/README.md
+++ b/fixtures/reconciler/README.md
@@ -4,13 +4,10 @@ This folder exists for **React contributors** only.
 If you use React you don't need to worry about it.
 
 These fixtures are a smoke-screen verification that the built React Reconciler distribution works.
-**They are not running automatically.** (At least not yet, feel free to contribute to automate them.)
-
-Run them when you make changes to how we package React or perform any release.
 
 To test, from the project root:
 * `yarn build`
-* `pushd fixtures/reconciler; yarn install && yarn test; popd`
-
-If everything is okay then you should see `Ok!` printed to the console.
+* `cd fixtures/reconciler`
+* `yarn test`
 
+They should run as part of the CI check.
diff --git a/fixtures/reconciler/index.js b/fixtures/reconciler/index.js
index 248ff0e073d52..b1780069929d8 100644
--- a/fixtures/reconciler/index.js
+++ b/fixtures/reconciler/index.js
@@ -249,16 +249,6 @@ var Noop = {
     NoopRenderer.updateContainer(element, root, null, callback);
   },
 
-  unmountRootWithID(rootID: string) {
-    const root = roots.get(rootID);
-    if (root) {
-      NoopRenderer.updateContainer(null, root, null, () => {
-        roots.delete(rootID);
-        rootContainers.delete(rootID);
-      });
-    }
-  },
-
   flush(): Array<mixed> {
     return Noop.flushUnitsOfWork(Infinity);
   },
@@ -280,9 +270,23 @@ var Noop = {
   flushSync: NoopRenderer.flushSync,
 };
 
-class Comp extends React.Component {
+type TestProps = {|
+  active: boolean,
+|};
+type TestState = {|
+  counter: number,
+|};
+
+let instance = null;
+class Test extends React.Component<TestProps, TestState> {
+  state = {counter: 0};
+  increment() {
+    this.setState(({counter}) => ({
+      counter: counter + 1,
+    }));
+  }
   render() {
-    return this.props.active ? 'Active Comp' : 'Deactive Comp';
+    return [this.props.active ? 'Active' : 'Inactive', this.state.counter];
   }
 }
 const Children = props => props.children;
@@ -292,13 +296,46 @@ Noop.render(
     <Children>
       Hello world
       <span>{'Number '}{42}</span>
-      <Comp active />
+      <Test active={true} ref={t => (instance = t)} />
     </Children>
   </main>
 );
 Noop.flush();
-const actual = Noop.getChildren();
-const expected = [
+const actual1 = Noop.getChildren();
+const expected1 = [
+  {
+    type: 'main',
+    children: [
+      {type: 'div', children: [], prop: undefined},
+      {text: 'Hello world'},
+      {
+        type: 'span',
+        children: [{text: 'Number '}, {text: '42'}],
+        prop: undefined,
+      },
+      {text: 'Active'},
+      {text: '0'},
+    ],
+    prop: undefined,
+  },
+];
+assert.deepEqual(
+  actual1,
+  expected1,
+  'Error. Noop.getChildren() returned unexpected value.\nExpected:\  ' +
+    JSON.stringify(expected1, null, 2) +
+    '\n\nActual:\n  ' +
+    JSON.stringify(actual1, null, 2)
+);
+
+if (instance === null) {
+  throw new Error('Expected instance to exist.');
+}
+
+instance.increment();
+Noop.flush();
+const actual2 = Noop.getChildren();
+const expected2 = [
   {
     type: 'main',
     children: [
@@ -309,18 +346,21 @@ const expected = [
         children: [{text: 'Number '}, {text: '42'}],
         prop: undefined,
       },
-      {text: 'Active Comp'},
+      {text: 'Active'},
+      {text: '1'},
     ],
     prop: undefined,
   },
 ];
 assert.deepEqual(
-  actual,
-  expected,
+  actual2,
+  expected2,
   'Error. Noop.getChildren() returned unexpected value.\nExpected:\  ' +
-    JSON.stringify(expected, null, 2) +
+    JSON.stringify(expected2, null, 2) +
     '\n\nActual:\n  ' +
-    JSON.stringify(actual, null, 2)
+    JSON.stringify(actual2, null, 2)
 );
 
-console.log('Reconciler package is Ok!');
+const beginGreen = '\u001b[32m';
+const endGreen = '\u001b[39m';
+console.log(beginGreen + 'Reconciler package is OK!' + endGreen);
diff --git a/fixtures/reconciler/package.json b/fixtures/reconciler/package.json
index abe75ffad2dba..d036f41ecc7dc 100644
--- a/fixtures/reconciler/package.json
+++ b/fixtures/reconciler/package.json
@@ -2,12 +2,9 @@
   "name": "react-fixtures",
   "version": "0.1.0",
   "private": true,
-  "dependencies": {
-    "react": "^16.0.0",
-    "react-reconciler": "file:../../build/packages/react-reconciler"
-  },
   "scripts": {
-    "start": "../../node_modules/.bin/babel-node ./index",
-    "test": "../../node_modules/.bin/babel-node ./index"
+    "test:dev": "NODE_PATH=../../build/packages ../../node_modules/.bin/babel-node ./index",
+    "test:prod": "NODE_PATH=../../build/packages NODE_ENV=production ../../node_modules/.bin/babel-node ./index",
+    "test": "npm run test:dev && npm run test:prod"
   }
 }
diff --git a/fixtures/reconciler/yarn.lock b/fixtures/reconciler/yarn.lock
deleted file mode 100644
index b843eb76e551f..0000000000000
--- a/fixtures/reconciler/yarn.lock
+++ /dev/null
@@ -1,108 +0,0 @@
-# THIS IS AN AUTOGENERATED FILE. DO NOT EDIT THIS FILE DIRECTLY.
-# yarn lockfile v1
-
-
-asap@~2.0.3:
-  version "2.0.6"
-  resolved "https://registry.yarnpkg.com/asap/-/asap-2.0.6.tgz#e50347611d7e690943208bbdafebcbc2fb866d46"
-
-core-js@^1.0.0:
-  version "1.2.7"
-  resolved "https://registry.yarnpkg.com/core-js/-/core-js-1.2.7.tgz#652294c14651db28fa93bd2d5ff2983a4f08c636"
-
-encoding@^0.1.11:
-  version "0.1.12"
-  resolved "https://registry.yarnpkg.com/encoding/-/encoding-0.1.12.tgz#538b66f3ee62cd1ab51ec323829d1f9480c74beb"
-  dependencies:
-    iconv-lite "~0.4.13"
-
-fbjs@^0.8.16:
-  version "0.8.16"
-  resolved "https://registry.yarnpkg.com/fbjs/-/fbjs-0.8.16.tgz#5e67432f550dc41b572bf55847b8aca64e5337db"
-  dependencies:
-    core-js "^1.0.0"
-    isomorphic-fetch "^2.1.1"
-    loose-envify "^1.0.0"
-    object-assign "^4.1.0"
-    promise "^7.1.1"
-    setimmediate "^1.0.5"
-    ua-parser-js "^0.7.9"
-
-iconv-lite@~0.4.13:
-  version "0.4.19"
-  resolved "https://registry.yarnpkg.com/iconv-lite/-/iconv-lite-0.4.19.tgz#f7468f60135f5e5dad3399c0a81be9a1603a082b"
-
-is-stream@^1.0.1:
-  version "1.1.0"
-  resolved "https://registry.yarnpkg.com/is-stream/-/is-stream-1.1.0.tgz#12d4a3dd4e68e0b79ceb8dbc84173ae80d91ca44"
-
-isomorphic-fetch@^2.1.1:
-  version "2.2.1"
-  resolved "https://registry.yarnpkg.com/isomorphic-fetch/-/isomorphic-fetch-2.2.1.tgz#611ae1acf14f5e81f729507472819fe9733558a9"
-  dependencies:
-    node-fetch "^1.0.1"
-    whatwg-fetch ">=0.10.0"
-
-js-tokens@^3.0.0:
-  version "3.0.2"
-  resolved "https://registry.yarnpkg.com/js-tokens/-/js-tokens-3.0.2.tgz#9866df395102130e38f7f996bceb65443209c25b"
-
-loose-envify@^1.0.0, loose-envify@^1.1.0, loose-envify@^1.3.1:
-  version "1.3.1"
-  resolved "https://registry.yarnpkg.com/loose-envify/-/loose-envify-1.3.1.tgz#d1a8ad33fa9ce0e713d65fdd0ac8b748d478c848"
-  dependencies:
-    js-tokens "^3.0.0"
-
-node-fetch@^1.0.1:
-  version "1.7.3"
-  resolved "https://registry.yarnpkg.com/node-fetch/-/node-fetch-1.7.3.tgz#980f6f72d85211a5347c6b2bc18c5b84c3eb47ef"
-  dependencies:
-    encoding "^0.1.11"
-    is-stream "^1.0.1"
-
-object-assign@^4.1.0, object-assign@^4.1.1:
-  version "4.1.1"
-  resolved "https://registry.yarnpkg.com/object-assign/-/object-assign-4.1.1.tgz#2109adc7965887cfc05cbbd442cac8bfbb360863"
-
-promise@^7.1.1:
-  version "7.3.1"
-  resolved "https://registry.yarnpkg.com/promise/-/promise-7.3.1.tgz#064b72602b18f90f29192b8b1bc418ffd1ebd3bf"
-  dependencies:
-    asap "~2.0.3"
-
-prop-types@^15.6.0:
-  version "15.6.0"
-  resolved "https://registry.yarnpkg.com/prop-types/-/prop-types-15.6.0.tgz#ceaf083022fc46b4a35f69e13ef75aed0d639856"
-  dependencies:
-    fbjs "^0.8.16"
-    loose-envify "^1.3.1"
-    object-assign "^4.1.1"
-
-"react-reconciler@file:../../build/packages/react-reconciler":
-  version "0.1.0"
-  dependencies:
-    fbjs "^0.8.16"
-    loose-envify "^1.1.0"
-    object-assign "^4.1.1"
-    prop-types "^15.6.0"
-
-react@^16.0.0:
-  version "16.0.0"
-  resolved "https://registry.yarnpkg.com/react/-/react-16.0.0.tgz#ce7df8f1941b036f02b2cca9dbd0cb1f0e855e2d"
-  dependencies:
-    fbjs "^0.8.16"
-    loose-envify "^1.1.0"
-    object-assign "^4.1.1"
-    prop-types "^15.6.0"
-
-setimmediate@^1.0.5:
-  version "1.0.5"
-  resolved "https://registry.yarnpkg.com/setimmediate/-/setimmediate-1.0.5.tgz#290cbb232e306942d7d7ea9b83732ab7856f8285"
-
-ua-parser-js@^0.7.9:
-  version "0.7.14"
-  resolved "https://registry.yarnpkg.com/ua-parser-js/-/ua-parser-js-0.7.14.tgz#110d53fa4c3f326c121292bbeac904d2e03387ca"
-
-whatwg-fetch@>=0.10.0:
-  version "2.0.3"
-  resolved "https://registry.yarnpkg.com/whatwg-fetch/-/whatwg-fetch-2.0.3.tgz#9c84ec2dcf68187ff00bc64e1274b442176e1c84"
diff --git a/scripts/circleci/build.sh b/scripts/circleci/build.sh
index 49bb2128657cf..4f0c1521677c4 100755
--- a/scripts/circleci/build.sh
+++ b/scripts/circleci/build.sh
@@ -3,4 +3,8 @@
 set -e		
 		
 npm run build -- --extract-errors
-git checkout -- scripts/error-codes/codes.json		
\ No newline at end of file
+git checkout -- scripts/error-codes/codes.json
+
+# Check that the standalone reconciler isn't borked
+cd fixtures/reconciler
+yarn test
diff --git a/scripts/rollup/build.js b/scripts/rollup/build.js
index d9c3e0db57f68..eb9cbe346d0d9 100644
--- a/scripts/rollup/build.js
+++ b/scripts/rollup/build.js
@@ -81,6 +81,12 @@ function getHeaderSanityCheck(bundleType, hasteName) {
 }
 
 function getBanner(bundleType, hasteName, filename, moduleType) {
+  if (moduleType === RECONCILER) {
+    // Standalone reconciler is only used by third-party renderers.
+    // It is handled separately.
+    return getReconcilerBanner(bundleType, filename);
+  }
+
   switch (bundleType) {
     // UMDs are not wrapped in conditions.
     case UMD_DEV:
@@ -91,17 +97,10 @@ function getBanner(bundleType, hasteName, filename, moduleType) {
       let banner = Header.getHeader(filename, reactVersion);
       // Wrap the contents of the if-DEV check with an IIFE.
       // Block-level function definitions can cause problems for strict mode.
-      banner += moduleType === RECONCILER
-        ? `'use strict';\n\n\nif (process.env.NODE_ENV !== "production") {\nmodule.exports = function(config) {\n`
-        : `'use strict';\n\n\nif (process.env.NODE_ENV !== "production") {\n(function() {\n`;
+      banner += `'use strict';\n\n\nif (process.env.NODE_ENV !== "production") {\n(function() {\n`;
       return banner;
     case NODE_PROD:
-      return (
-        Header.getHeader(filename, reactVersion) +
-        (moduleType === RECONCILER
-          ? `\n\n'use strict';\n\n\nmodule.exports = function(config) {\n`
-          : '')
-      );
+      return Header.getHeader(filename, reactVersion);
     // All FB and RN bundles need Haste headers.
     // DEV bundle is guarded to help weak dead code elimination.
     case FB_DEV:
@@ -123,11 +122,11 @@ function getBanner(bundleType, hasteName, filename, moduleType) {
 
 function getFooter(bundleType, filename, moduleType) {
   if (moduleType === RECONCILER) {
-    return (
-      '\nreturn ReactFiberReconciler(config);\n};\n' +
-      (bundleType === NODE_DEV ? '}\n' : '')
-    );
+    // Standalone reconciler is only used by third-party renderers.
+    // It is handled separately.
+    return getReconcilerFooter(bundleType);
   }
+
   // Only need a footer if getBanner() has an opening brace.
   switch (bundleType) {
     // Non-UMD DEV bundles need conditions to help weak dead code elimination.
@@ -140,6 +139,45 @@ function getFooter(bundleType, filename, moduleType) {
   }
 }
 
+// TODO: this is extremely gross.
+// But it only affects the "experimental" standalone reconciler build.
+// The goal is to avoid having any shared state between renderers sharing it on npm.
+// Ideally we should just remove shared state in all Fiber modules and then lint against it.
+// But for now, we store the exported function in a variable, and then put the rest of the code
+// into a closure that makes all module-level state private to each call.
+const RECONCILER_WRAPPER_INTRO = `var $$$reconciler;\nmodule.exports = function(config) {\n`;
+const RECONCILER_WRAPPER_OUTRO = `return ($$$reconciler || ($$$reconciler = module.exports))(config);\n};\n`;
+
+function getReconcilerBanner(bundleType, filename) {
+  let banner = `${Header.getHeader(filename, reactVersion)}\n\n'use strict';\n\n\n`;
+  switch (bundleType) {
+    case NODE_DEV:
+      banner += `if (process.env.NODE_ENV !== "production") {\n${RECONCILER_WRAPPER_INTRO}`;
+      break;
+    case NODE_PROD:
+      banner += RECONCILER_WRAPPER_INTRO;
+      break;
+    default:
+      throw new Error(
+        'Standalone reconciler does not support ' + bundleType + ' builds.'
+      );
+  }
+  return banner;
+}
+
+function getReconcilerFooter(bundleType) {
+  switch (bundleType) {
+    case NODE_DEV:
+      return `\n${RECONCILER_WRAPPER_OUTRO}\n}`;
+    case NODE_PROD:
+      return `\n${RECONCILER_WRAPPER_OUTRO}`;
+    default:
+      throw new Error(
+        'Standalone reconciler does not support ' + bundleType + ' builds.'
+      );
+  }
+}
+
 function updateBabelConfig(babelOpts, bundleType, filename) {
   switch (bundleType) {
     case FB_DEV:

From a935605170aa6a8185666238745dc4a49a676821 Mon Sep 17 00:00:00 2001
From: Dan Abramov <dan.abramov@gmail.com>
Date: Wed, 11 Oct 2017 19:09:49 +0100
Subject: [PATCH 24/25] Record sizes

---
 scripts/rollup/results.json | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/scripts/rollup/results.json b/scripts/rollup/results.json
index e0808eef81bdc..1e345fb8c752f 100644
--- a/scripts/rollup/results.json
+++ b/scripts/rollup/results.json
@@ -57,12 +57,12 @@
       "gzip": 11028
     },
     "react-dom-unstable-native-dependencies.development.js (UMD_DEV)": {
-      "size": 86854,
-      "gzip": 21985
+      "size": 84930,
+      "gzip": 21288
     },
     "react-dom-unstable-native-dependencies.production.min.js (UMD_PROD)": {
-      "size": 15251,
-      "gzip": 5010
+      "size": 14441,
+      "gzip": 4650
     },
     "react-dom-unstable-native-dependencies.development.js (NODE_DEV)": {
       "size": 80723,
@@ -207,6 +207,14 @@
     "react-dom-test-utils.production.min.js (NODE_PROD)": {
       "size": 11608,
       "gzip": 4241
+    },
+    "react-reconciler.development.js (NODE_DEV)": {
+      "size": 279927,
+      "gzip": 58576
+    },
+    "react-reconciler.production.min.js (NODE_PROD)": {
+      "size": 38630,
+      "gzip": 12165
     }
   }
 }
\ No newline at end of file

From 04ec04ebcc69a25fb87039b8fd599b82de5dfd45 Mon Sep 17 00:00:00 2001
From: Dan Abramov <dan.abramov@gmail.com>
Date: Wed, 11 Oct 2017 19:11:02 +0100
Subject: [PATCH 25/25] Update README.md

---
 packages/react-reconciler/README.md | 46 ++++++++++++++++-------------
 1 file changed, 26 insertions(+), 20 deletions(-)

diff --git a/packages/react-reconciler/README.md b/packages/react-reconciler/README.md
index 3d4ce8d9f3770..f108413a9e911 100644
--- a/packages/react-reconciler/README.md
+++ b/packages/react-reconciler/README.md
@@ -1,33 +1,39 @@
 # react-reconciler
 
-An npm package to let you create custom reconcilers.
+This is an experimental package for creating custom React renderers.
 
-## Example Usage
+**Its API is not as stable as that of React, React Native, or React DOM, and does not follow the common versioning scheme.**
+
+**Use it at your own risk.**
+
+## API
 
 ```js
 var Reconciler = require('react-reconciler');
 
-var ReconcilerConfig = { /* ... */ };
-var Renderer = Reconciler(ReconcilerConfig);
+var ReconcilerConfig = {
+  // You'll need to implement some methods here.
+  // See below for more information and examples.
+};
+
+var MyRenderer = Reconciler(ReconcilerConfig);
+
 var RendererPublicAPI = {
-  render(
-    element: React$Element<any>,
-    container: DOMContainer,
-    callback: ?Function,
-  ) {
-    let root = container._reactRootContainer;
-    if (!root) {
-      const newRoot = Renderer.createContainer(container);
-      root = container._reactRootContainer = newRoot;
-      // Initial mount should not be batched.
-      Renderer.unbatchedUpdates(() => {
-        Renderer.updateContainer(element, newRoot, null, callback);
-      });
-    } else {
-      Renderer.updateContainer(element, root, null, callback);
-    }
+  render(element, container, callback) {
+    // Call MyRenderer.updateContainer() to schedule changes on the roots.
+    // See ReactDOM, React Native, or React ART for practical examples.
   }
 };
 
 module.exports = RendererPublicAPI;
 ```
+
+## Practical Examples
+
+* [React ART](https://github.com/facebook/react/blob/master/src/renderers/art/ReactARTFiberEntry.js)
+* [React DOM](https://github.com/facebook/react/blob/master/src/fb/ReactDOMFiberFBEntry.js)
+* [React Native](https://github.com/facebook/react/blob/master/src/renderers/native/ReactNativeFiberRenderer.js)
+
+If these links break please file an issue and we’ll fix them. They intentionally link to the latest versions since the API is still evolving.
+
+This [third-party tutorial](https://github.com/nitin42/Making-a-custom-React-renderer) is relatively up-to-date and may be helpful.