# Migration

- [Migration](#migration)
  - [From version 5.1.x to 5.2.x](#from-version-51x-to-52x)
    - [Source-loader](#source-loader)
    - [Default viewports](#default-viewports)
    - [Grid toolbar-feature](#grid-toolbar-feature)
    - [Docs mode docgen](#docs-mode-docgen)
    - [storySort option](#storysort-option)
  - [From version 5.1.x to 5.1.10](#from-version-51x-to-5110)
    - [babel.config.js support](#babelconfigjs-support)
  - [From version 5.0.x to 5.1.x](#from-version-50x-to-51x)
    - [React native server](#react-native-server)
    - [Angular 7](#angular-7)
    - [CoreJS 3](#corejs-3)
  - [From version 5.0.1 to 5.0.2](#from-version-501-to-502)
    - [Deprecate webpack extend mode](#deprecate-webpack-extend-mode)
  - [From version 4.1.x to 5.0.x](#from-version-41x-to-50x)
    - [sortStoriesByKind](#sortstoriesbykind)
    - [Webpack config simplification](#webpack-config-simplification)
    - [Theming overhaul](#theming-overhaul)
    - [Story hierarchy defaults](#story-hierarchy-defaults)
    - [Options addon deprecated](#options-addon-deprecated)
    - [Individual story decorators](#individual-story-decorators)
    - [Addon backgrounds uses parameters](#addon-backgrounds-uses-parameters)
    - [Addon cssresources name attribute renamed](#addon-cssresources-name-attribute-renamed)
    - [Addon viewport uses parameters](#addon-viewport-uses-parameters)
    - [Addon a11y uses parameters, decorator renamed](#addon-a11y-uses-parameters-decorator-renamed)
    - [New keyboard shortcuts defaults](#new-keyboard-shortcuts-defaults)
    - [New URL structure](#new-url-structure)
    - [Rename of the `--secure` cli parameter to `--https`](#rename-of-the---secure-cli-parameter-to---https)
    - [Vue integration](#vue-integration)
  - [From version 4.0.x to 4.1.x](#from-version-40x-to-41x)
    - [Private addon config](#private-addon-config)
    - [React 15.x](#react-15x)
  - [From version 3.4.x to 4.0.x](#from-version-34x-to-40x)
    - [React 16.3+](#react-163)
    - [Generic addons](#generic-addons)
    - [Knobs select ordering](#knobs-select-ordering)
    - [Knobs URL parameters](#knobs-url-parameters)
    - [Keyboard shortcuts moved](#keyboard-shortcuts-moved)
    - [Removed addWithInfo](#removed-addwithinfo)
    - [Removed RN packager](#removed-rn-packager)
    - [Removed RN addons](#removed-rn-addons)
    - [Storyshots Changes](#storyshots-changes)
    - [Webpack 4](#webpack-4)
    - [Babel 7](#babel-7)
    - [Create-react-app](#create-react-app)
      - [Upgrade CRA1 to babel 7](#upgrade-cra1-to-babel-7)
      - [Migrate CRA1 while keeping babel 6](#migrate-cra1-while-keeping-babel-6)
    - [start-storybook opens browser](#start-storybook-opens-browser)
    - [CLI Rename](#cli-rename)
    - [Addon story parameters](#addon-story-parameters)
  - [From version 3.3.x to 3.4.x](#from-version-33x-to-34x)
  - [From version 3.2.x to 3.3.x](#from-version-32x-to-33x)
    - [`babel-core` is now a peer dependency (#2494)](#babel-core-is-now-a-peer-dependency-2494)
    - [Base webpack config now contains vital plugins (#1775)](#base-webpack-config-now-contains-vital-plugins-1775)
    - [Refactored Knobs](#refactored-knobs)
  - [From version 3.1.x to 3.2.x](#from-version-31x-to-32x)
    - [Moved TypeScript addons definitions](#moved-typescript-addons-definitions)
    - [Updated Addons API](#updated-addons-api)
  - [From version 3.0.x to 3.1.x](#from-version-30x-to-31x)
    - [Moved TypeScript definitions](#moved-typescript-definitions)
    - [Deprecated head.html](#deprecated-headhtml)
  - [From version 2.x.x to 3.x.x](#from-version-2xx-to-3xx)
    - [Webpack upgrade](#webpack-upgrade)
    - [Packages renaming](#packages-renaming)
    - [Deprecated embedded addons](#deprecated-embedded-addons)

## From version 5.1.x to 5.2.x

### Source-loader

Addon-storysource contains a loader, `@storybook/addon-storysource/loader`, which has been deprecated in 5.2. If you use it, you'll see the warning:

```
@storybook/addon-storysource/loader is deprecated, please use @storybook/source-loader instead.
```

To upgrade to `@storybook/source-loader`, simply `npm install -D @storybook/source-loader` (or use `yarn`), and replace every instance of `@storybook/addon-storysource/loader` with `@storybook/source-loader`.

### Default viewports

The default viewports have been reduced to a smaller set, we think is enough for most use cases.
You can get the old default back by adding the following to your `config.js`:

```js
import { INITIAL_VIEWPORTS } from '@storybook/addon-viewport';

addParameters({
  viewport: {
    viewports: INITIAL_VIEWPORTS,
  },
});
```

### Grid toolbar-feature

The grid feature in the toolbar has been relocated to [addon-background](https://github.com/storybookjs/storybook/tree/next/addons/backgrounds), follow the setup intructions on that addon to get the feature again.

### Docs mode docgen

This isn't a breaking change per se, because `addon-docs` is a new feature. However it's intended to replace `addon-info`, so if you're migrating from `addon-info` there are a few things you should know:

1. Support for only one prop table
2. Prop table docgen info should be stored on the component and not in the global variable `STORYBOOK_REACT_CLASSES` as before.

### storySort option

In 5.0.x the global option `sortStoriesByKind` option was [inadverttly removed](#sortstoriesbykind). In 5.2 we've introduced a new option, `storySort`, to replace it. `storySort` takes a comparator function, so it is strictly more powerful than `sortStoriesByKind`.

For example, here's how to sort by story ID using `storySort`:

```js
addParameters({
  options: {
    storySort: (a, b) =>
      a[1].kind === b[1].kind ? 0 : a[1].id.localeCompare(b[1].id, { numeric: true }),
  },
});
```

## From version 5.1.x to 5.1.10

### babel.config.js support

SB 5.1.0 added [support for project root `babel.config.js` files](https://github.com/storybookjs/storybook/pull/6634), which was an [unintentional breaking change](https://github.com/storybookjs/storybook/issues/7058#issuecomment-515398228). 5.1.10 fixes this, but if you relied on project root `babel.config.js` support, this bugfix is a breaking change. The workaround is to copy the file into your `.storybook` config directory. We may add back project-level support in 6.0.

## From version 5.0.x to 5.1.x

### React native server

Storybook 5.1 contains a major overhaul of `@storybook/react-native` as compared to 4.1 (we didn't ship a version of RN in 5.0 due to timing constraints). Storybook for RN consists of an an UI for browsing stories on-device or in a simulator, and an optional webserver which can also be used to browse stories and web addons.

5.1 refactors both pieces:

- `@storybook/react-native` no longer depends on the Storybook UI and only contains on-device functionality
- `@storybook/react-native-server` is a new package for those who wish to run a web server alongside their device UI

In addition, both packages share more code with the rest of Storybook, which will reduce bugs and increase compatibility (e.g. with the latest versions of babel, etc.).

As a user with an existing 4.1.x RN setup, no migration should be necessary to your RN app. Simply upgrading the library should be enough.

If you wish to run the optional web server, you will need to do the following migration:

- Add `babel-loader` as a dev dependency
- Add `@storybook/react-native-server` as a dev dependency
- Change your "storybook" `package.json` script from `storybook start [-p ...]` to `start-storybook [-p ...]`

And with that you should be good to go!

### Angular 7

Storybook 5.1 relies on `core-js@^3.0.0` and therefore causes a conflict with Angular 7 that relies on `core-js@^2.0.0`. In order to get Storybook running on Angular 7 you can either update to Angular 8 (which dropped `core-js` as a dependency) or follow these steps:

- Remove `node_modules/@storybook`
- `npm i core-js@^3.0.0` / `yarn add core-js@^3.0.0`
- Add the following paths to your `tsconfig.json`

```json
{
  "compilerOptions": {
    "paths": {
      "core-js/es7/reflect": ["node_modules/core-js/proposals/reflect-metadata"],
      "core-js/es6/*": ["node_modules/core-js/es"]
    }
  }
}
```

You should now be able to run Storybook and Angular 7 without any errors.

Reference issue: [https://github.com/angular/angular-cli/issues/13954](https://github.com/angular/angular-cli/issues/13954)

### CoreJS 3

Following the rest of the JS ecosystem, Storybook 5.1 upgrades [CoreJS](https://github.com/zloirock/core-js) 2 to 3, which is a breaking change.

This upgrade is problematic because many apps/libraries still rely on CoreJS 2, and many users get corejs-related errors due to bad resolution. To address this, we're using [corejs-upgrade-webpack-plugin](https://github.com/ndelangen/corejs-upgrade-webpack-plugin), which attempts to automatically upgrade code to CoreJS 3.

After a few iterations, this approach seems to be working. However, there are a few exceptions:

- If your app uses `babel-polyfill`, try to remove it

We'll update this section as we find more problem cases. If you have a `core-js` problem, please file an issue (preferably with a repro), and we'll do our best to get you sorted.

## From version 5.0.1 to 5.0.2

### Deprecate webpack extend mode

Exporting an object from your custom webpack config puts storybook in "extend mode".

There was a bad bug in `v5.0.0` involving webpack "extend mode" that caused webpack issues for users migrating from `4.x`. We've fixed this problem in `v5.0.2` but it means that extend-mode has a different behavior if you're migrating from `5.0.0` or `5.0.1`. In short, `4.x` extended a base config with the custom config, whereas `5.0.0-1` extended the base with a richer config object that could conflict with the custom config in different ways from `4.x`.

We've also deprecated "extend mode" because it doesn't add a lot of value over "full control mode", but adds more code paths, documentation, user confusion etc. Starting in SB6.0 we will only support "full control mode" customization.

To migrate from extend-mode to full-control mode, if your extend-mode webpack config looks like this:

```js
module.exports = {
  module: {
    rules: [
      /* ... */
    ],
  },
};
```

In full control mode, you need modify the default config to have the rules of your liking:

```js
module.exports = ({ config }) => ({
  ...config,
  module: {
    ...config.module,
    rules: [
      /* your own rules "..." here and/or some subset of config.module.rules */
    ],
  },
});
```

Please refer to the [current custom webpack documentation](https://github.com/storybookjs/storybook/blob/next/docs/src/pages/configurations/custom-webpack-config/index.md) for more information on custom webpack config and to [Issue #6081](https://github.com/storybookjs/storybook/issues/6081) for more information about the change.

## From version 4.1.x to 5.0.x

Storybook 5.0 includes sweeping UI changes as well as changes to the addon API and custom webpack configuration. We've tried to keep backwards compatibility in most cases, but there are some notable exceptions documented below.

### sortStoriesByKind

In Storybook 5.0 we changed a lot of UI related code, and 1 oversight caused the `sortStoriesByKind` options to stop working.
We're working on providing a better way of sorting stories for now the feature has been removed. Stories appear in the order they are loaded.

If you're using webpack's `require.context` to load stories, you can sort the execution of requires:

```js
var context = require.context('../stories', true, /\.stories\.js$/);
var modules = context.keys();

// sort them
var sortedModules = modules.slice().sort((a, b) => {
  // sort the stories based on filename/path
  return a < b ? -1 : a > b ? 1 : 0;
});

// execute them
sortedModules.forEach(key => {
  context(key);
});
```

### Webpack config simplification

The API for custom webpack configuration has been simplifed in 5.0, but it's a breaking change. Storybook's "full control mode" for webpack allows you to override the webpack config with a function that returns a configuration object.

In Storybook 5 there is a single signature for full-control mode that takes a parameters object with the fields `config` and `mode`:

```js
module.exports = ({ config, mode }) => { config.module.rules.push(...); return config; }
```

In contrast, the 4.x configuration function accepted either two or three arguments (`(baseConfig, mode)`, or `(baseConfig, mode, defaultConfig)`). The `config` object in the 5.x signature is equivalent to 4.x's `defaultConfig`.

Please see the [current custom webpack documentation](https://github.com/storybookjs/storybook/blob/next/docs/src/pages/configurations/custom-webpack-config/index.md) for more information on custom webpack config.

### Theming overhaul

Theming has been rewritten in v5. If you used theming in v4, please consult the [theming docs](https://github.com/storybookjs/storybook/blob/next/docs/src/pages/configurations/theming/index.md) to learn about the new API.

### Story hierarchy defaults

Storybook's UI contains a hierarchical tree of stories that can be configured by `hierarchySeparator` and `hierarchyRootSeparator` [options](./addons/options/README.md).

In Storybook 4.x the values defaulted to `null` for both of these options, so that there would be no hierarchy by default.

In 5.0, we now provide recommended defaults:

```js
{
  hierarchyRootSeparator: '|',
  hierarchySeparator: /\/|\./,
}
```

This means if you use the characters { `|`, `/`, `.` } in your story kinds it will triggger the story hierarchy to appear. For example `storiesOf('UI|Widgets/Basics/Button')` will create a story root called `UI` containing a `Widgets/Basics` group, containing a `Button` component.

If you wish to opt-out of this new behavior and restore the flat UI, simply set them back to `null` in your storybook config, or remove { `|`, `/`, `.` } from your story kinds:

```js
addParameters({
  options: {
    hierarchyRootSeparator: null,
    hierarchySeparator: null,
  },
});
```

### Options addon deprecated

In 4.x we added story parameters. In 5.x we've deprecated the options addon in favor of [global parameters](./docs/src/pages/configurations/options-parameter/index.md), and we've also renamed some of the options in the process (though we're maintaining backwards compatibility until 6.0).

Here's an old configuration:

```js
addDecorator(
  withOptions({
    name: 'Storybook',
    url: 'https://storybook.js.org',
    goFullScreen: false,
    addonPanelInRight: true,
  })
);
```

And here's its new counterpart:

```js
import { create } from '@storybook/theming';
addParameters({
  options: {
    theme: create({
      base: 'light',
      brandTitle: 'Storybook',
      brandUrl: 'https://storybook.js.org',
      // To control appearance:
      // brandImage: 'http://url.of/some.svg',
    }),
    isFullscreen: false,
    panelPosition: 'right',
    isToolshown: true,
  },
});
```

Here is the mapping from old options to new:

| Old               | New              |
| ----------------- | ---------------- |
| name              | theme.brandTitle |
| url               | theme.brandUrl   |
| goFullScreen      | isFullscreen     |
| showStoriesPanel  | showNav          |
| showAddonPanel    | showPanel        |
| addonPanelInRight | panelPosition    |
| showSearchBox     |                  |
|                   | isToolshown      |

Storybook v5 removes the search dialog box in favor of a quick search in the navigation view, so `showSearchBox` has been removed.

Storybook v5 introduce a new tool bar above the story view and you can show\hide it with the new `isToolshown` option.

### Individual story decorators

The behavior of adding decorators to a kind has changed in SB5 ([#5781](https://github.com/storybookjs/storybook/issues/5781)).

In SB4 it was possible to add decorators to only a subset of the stories of a kind.

```js
storiesOf('Stories', module)
  .add('noncentered', () => 'Hello')
  .addDecorator(centered)
  .add('centered', () => 'Hello');
```

The semantics has changed in SB5 so that calling `addDecorator` on a kind adds a decorator to all its stories, no matter the order. So in the previous example, both stories would be centered.

To allow for a subset of the stories in a kind to be decorated, we've added the ability to add decorators to individual stories using parameters:

```js
storiesOf('Stories', module)
  .add('noncentered', () => 'Hello')
  .add('centered', () => 'Hello', { decorators: [centered] });
```

### Addon backgrounds uses parameters

Similarly, `@storybook/addon-backgrounds` uses parameters to pass background options. If you previously had:

```js
import { withBackgrounds } from `@storybook/addon-backgrounds`;

storiesOf('Stories', module)
  .addDecorator(withBackgrounds(options));
```

You should replace it with:

```js
storiesOf('Stories', module).addParameters({ backgrounds: options });
```

You can pass `backgrounds` parameters at the global level (via `addParameters` imported from `@storybook/react` et al.), and the story level (via the third argument to `.add()`).

### Addon cssresources name attribute renamed

In the options object for `@storybook/addon-cssresources`, the `name` attribute for each resource has been renamed to `id`. If you previously had:

```js
import { withCssResources } from '@storybook/addon-cssresources';
import { addDecorator } from '@storybook/react';

addDecorator(
  withCssResources({
    cssresources: [
      {
        name: `bluetheme`, // Previous
        code: `<style>body { background-color: lightblue; }</style>`,
        picked: false,
      },
    ],
  })
);
```

You should replace it with:

```js
import { withCssResources } from '@storybook/addon-cssresources';
import { addDecorator } from '@storybook/react';

addDecorator(
  withCssResources({
    cssresources: [
      {
        id: `bluetheme`, // Renamed
        code: `<style>body { background-color: lightblue; }</style>`,
        picked: false,
      },
    ],
  })
);
```

### Addon viewport uses parameters

Similarly, `@storybook/addon-viewport` uses parameters to pass viewport options. If you previously had:

```js
import { configureViewport } from `@storybook/addon-viewport`;

configureViewport(options);
```

You should replace it with:

```js
import { addParameters } from '@storybook/react'; // or others

addParameters({ viewport: options });
```

The `withViewport` decorator is also no longer supported and should be replaced with a parameter based API as above. Also the `onViewportChange` callback is no longer supported.

See the [viewport addon README](https://github.com/storybookjs/storybook/blob/master/addons/viewport/README.md) for more information.

### Addon a11y uses parameters, decorator renamed

Similarly, `@storybook/addon-a11y` uses parameters to pass a11y options. If you previously had:

```js
import { configureA11y } from `@storybook/addon-a11y`;

configureA11y(options);
```

You should replace it with:

```js
import { addParameters } from '@storybook/react'; // or others

addParameters({ a11y: options });
```

You can also pass `a11y` parameters at the component level (via `storiesOf(...).addParameters`), and the story level (via the third argument to `.add()`).

Furthermore, the decorator `checkA11y` has been deprecated and renamed to `withA11y` to make it consistent with other Storybook decorators.

See the [a11y addon README](https://github.com/storybookjs/storybook/blob/master/addons/a11y/README.md) for more information.

### New keyboard shortcuts defaults

Storybook's keyboard shortcuts are updated in 5.0, but they are configurable via the menu so if you want to set them back you can:

| Shorctut               | Old         | New   |
| ---------------------- | ----------- | ----- |
| Toggle sidebar         | cmd-shift-X | S     |
| Toggle addons panel    | cmd-shift-Z | A     |
| Toggle addons position | cmd-shift-G | D     |
| Toggle fullscreen      | cmd-shift-F | F     |
| Next story             | cmd-shift-→ | alt-→ |
| Prev story             | cmd-shift-← | alt-← |
| Next component         |             | alt-↓ |
| Prev component         |             | alt-↑ |
| Search                 |             | /     |

### New URL structure

We've update Storybook's URL structure in 5.0. The old structure used URL parameters to save the UI state, resulting in long ugly URLs. v5 respects the old URL parameters, but largely does away with them.

The old structure encoded `selectedKind` and `selectedStory` among other parameters. Storybook v5 respects these parameters but will issue a deprecation message in the browser console warning of potential future removal.

The new URL structure looks like:

```
https://url-of-storybook?path=/story/<storyId>
```

The structure of `storyId` is a slugified `<selectedKind>--<selectedStory>` (slugified = lowercase, hyphen-separated). Each `storyId` must be unique. We plan to build more features into Storybook in upcoming versions based on this new structure.

### Rename of the `--secure` cli parameter to `--https`

Storybook for React Native's start commands & the Web versions' start command were a bit different, for no reason.
We've changed the start command for Reactnative to match the other.

This means that when you previously used the `--secure` flag like so:

```sh
start-storybook --secure
# or
start-storybook --s
```

You have to replace it with:

```sh
start-storybook --https
```

### Vue integration

The Vue integration was updated, so that every story returned from a story or decorator function is now being normalized with `Vue.extend` **and** is being wrapped by a functional component. Returning a string from a story or decorator function is still supported and is treated as a component with the returned string as the template.

Currently there is no recommended way of accessing the component options of a story inside a decorator.

## From version 4.0.x to 4.1.x

There are are a few migrations you should be aware of in 4.1, including one unintentionally breaking change for advanced addon usage.

### Private addon config

If your Storybook contains custom addons defined that are defined in your app (as opposed to installed from packages) and those addons rely on reconfiguring webpack/babel, Storybook 4.1 may break for you. There's a workaround [described in the issue](https://github.com/storybookjs/storybook/issues/4995), and we're working on official support in the next release.

### React 15.x

Storybook 4.1 supports React 15.x (which had been [lost in the 4.0 release](#react-163)). So if you've been blocked on upgrading, we've got you covered. You should be able to upgrade according to the 4.0 migration notes below, or following the [4.0 upgrade guide](https://medium.com/storybookjs/migrating-to-storybook-4-c65b19a03d2c).

## From version 3.4.x to 4.0.x

With 4.0 as our first major release in over a year, we've collected a lot of cleanup tasks. Most of the deprecations have been marked for months, so we hope that there will be no significant impact on your project. We've also created a [step-by-step guide to help you upgrade](https://medium.com/storybookjs/migrating-to-storybook-4-c65b19a03d2c).

### React 16.3+

Storybook uses [Emotion](https://emotion.sh/) for styling which currently requires React 16.3 and above.

If you're using Storybook for anything other than React, you probably don't need to worry about this.

However, if you're developing React components, this means you need to upgrade to 16.3 or higher to use Storybook 4.0.

> **NOTE:** This is a temporary requirement, and we plan to restore 15.x compatibility in a near-term 4.x release.

Also, here's the error you'll get if you're running an older version of React:

```

core.browser.esm.js:15 Uncaught TypeError: Object(...) is not a function
at Module../node_modules/@emotion/core/dist/core.browser.esm.js (core.browser.esm.js:15)
at **webpack_require** (bootstrap:724)
at fn (bootstrap:101)
at Module../node_modules/@emotion/styled-base/dist/styled-base.browser.esm.js (styled-base.browser.esm.js:1)
at **webpack_require** (bootstrap:724)
at fn (bootstrap:101)
at Module../node_modules/@emotion/styled/dist/styled.esm.js (styled.esm.js:1)
at **webpack_require** (bootstrap:724)
at fn (bootstrap:101)
at Object../node_modules/@storybook/components/dist/navigation/MenuLink.js (MenuLink.js:12)

```

### Generic addons

4.x introduces generic addon decorators that are not tied to specific view layers [#3555](https://github.com/storybookjs/storybook/pull/3555). So for example:

```js
import { number } from '@storybook/addon-knobs/react';
```

Becomes:

```js
import { number } from '@storybook/addon-knobs';
```

### Knobs select ordering

4.0 also reversed the order of addon-knob's `select` knob keys/values, which had been called `selectV2` prior to this breaking change. See the knobs [package README](https://github.com/storybookjs/storybook/blob/master/addons/knobs/README.md#select) for usage.

### Knobs URL parameters

Addon-knobs no longer updates the URL parameters interactively as you edit a knob. This is a UI change but it shouldn't break any code because old URLs are still supported.

In 3.x, editing knobs updated the URL parameters interactively. The implementation had performance and architectural problems. So in 4.0, we changed this to a "copy" button in the addon which generates a URL with the updated knob values and copies it to the clipboard.

### Keyboard shortcuts moved

- Addon Panel to `Z`
- Stories Panel to `X`
- Show Search to `O`
- Addon Panel right side to `G`

### Removed addWithInfo

`Addon-info`'s `addWithInfo` has been marked deprecated since 3.2. In 4.0 we've removed it completely. See the package [README](https://github.com/storybookjs/storybook/blob/master/addons/info/README.md) for the proper usage.

### Removed RN packager

Since storybook version v4.0 packager is removed from storybook. The suggested storybook usage is to include it inside your app.
If you want to keep the old behaviour, you have to start the packager yourself with a different project root.
`npm run storybook start -p 7007 | react-native start --projectRoot storybook`

Removed cli options: `--packager-port --root --projectRoots -r, --reset-cache --skip-packager --haul --platform --metro-config`

### Removed RN addons

The `@storybook/react-native` had built-in addons (`addon-actions` and `addon-links`) that have been marked as deprecated since 3.x. They have been fully removed in 4.x. If your project still uses the built-ins, you'll need to add explicit dependencies on `@storybook/addon-actions` and/or `@storybook/addon-links` and import directly from those packages.

### Storyshots Changes

1.  `imageSnapshot` test function was extracted from `addon-storyshots`
    and moved to a new package - `addon-storyshots-puppeteer` that now will
    be dependant on puppeteer. [README](https://github.com/storybookjs/storybook/tree/master/addons/storyshots/storyshots-puppeteer)
2.  `getSnapshotFileName` export was replaced with the `Stories2SnapsConverter`
    class that now can be overridden for a custom implementation of the
    snapshot-name generation. [README](https://github.com/storybookjs/storybook/tree/master/addons/storyshots/storyshots-core#stories2snapsconverter)
3.  Storybook that was configured with Webpack's `require.context()` feature
    will need to add a babel plugin to polyfill this functionality.
    A possible plugin might be [babel-plugin-require-context-hook](https://github.com/smrq/babel-plugin-require-context-hook).
    [README](https://github.com/storybookjs/storybook/tree/master/addons/storyshots/storyshots-core#configure-jest-to-work-with-webpacks-requirecontext)

### Webpack 4

Storybook now uses webpack 4. If you have a [custom webpack config](https://storybook.js.org/configurations/custom-webpack-config/), make sure that all the loaders and plugins you use support webpack 4.

### Babel 7

Storybook now uses Babel 7. There's a couple of cases when it can break with your app:

- If you aren't using Babel yourself, and don't have .babelrc, install following dependencies:
  ```
  npm i -D @babel/core babel-loader@next
  ```
- If you're using Babel 6, make sure that you have direct dependencies on `babel-core@6` and `babel-loader@7` and that you have a `.babelrc` in your project directory.

### Create-react-app

If you are using `create-react-app` (aka CRA), you may need to do some manual steps to upgrade, depending on the setup.

- `create-react-app@1` may require manual migrations.
  - If you're adding storybook for the first time, it should just work: `sb init` should add the correct dependencies.
  - If you're upgrading an existing project, your `package.json` probably already uses Babel 6, making it incompatible with `@storybook/react@4` which uses Babel 7. There are two ways to make it compatible, each of which is spelled out in detail in the next section:
    - Upgrade to Babel 7 if you are not dependent on Babel 6-specific features.
    - Migrate Babel 6 if you're heavily dependent on some Babel 6-specific features).
- `create-react-app@2` should be compatible as is, since it uses babel 7.

#### Upgrade CRA1 to babel 7

```
yarn remove babel-core babel-runtime
yarn add @babel/core babel-loader --dev
```

#### Migrate CRA1 while keeping babel 6

```
yarn add babel-loader@7
```

Also, make sure you have a `.babelrc` in your project directory. You probably already do if you are using Babel 6 features (otherwise you should consider upgrading to Babel 7 instead). If you don't have one, here's a simple one that works:

```json
{
  "presets": ["env", "react"]
}
```

### start-storybook opens browser

If you're using `start-storybook` on CI, you may need to opt out of this using the new `--ci` flag.

### CLI Rename

We've deprecated the `getstorybook` CLI in 4.0. The new way to install storybook is `sb init`. We recommend using `npx` for convenience and to make sure you're always using the latest version of the CLI:

```
npx -p @storybook/cli sb init
```

### Addon story parameters

Storybook 4 introduces story parameters, a more convenient way to configure how addons are configured.

```js
storiesOf('My component', module)
  .add('story1', withNotes('some notes')(() => <Component ... />))
  .add('story2', withNotes('other notes')(() => <Component ... />));
```

Becomes:

```js
// config.js
addDecorator(withNotes);

// Component.stories.js
storiesOf('My component', module)
  .add('story1', () => <Component ... />, { notes: 'some notes' })
  .add('story2', () => <Component ... />, { notes: 'other notes' });
```

This example applies notes globally to all stories. You can apply it locally with `storiesOf(...).addDecorator(withNotes)`.

The story parameters correspond directly to the old withX arguments, so it's easy to migrate your code. See the parameters documentation for the packages that have been upgraded:

- [Notes](https://github.com/storybookjs/storybook/blob/master/addons/notes/README.md)
- [Jest](https://github.com/storybookjs/storybook/blob/master/addons/jest/README.md)
- [Knobs](https://github.com/storybookjs/storybook/blob/master/addons/knobs/README.md)
- [Viewport](https://github.com/storybookjs/storybook/blob/master/addons/viewport/README.md)
- [Backgrounds](https://github.com/storybookjs/storybook/blob/master/addons/backgrounds/README.md)
- [Options](https://github.com/storybookjs/storybook/blob/master/addons/options/README.md)

## From version 3.3.x to 3.4.x

There are no expected breaking changes in the 3.4.x release, but 3.4 contains a major refactor to make it easier to support new frameworks, and we will document any breaking changes here if they arise.

## From version 3.2.x to 3.3.x

It wasn't expected that there would be any breaking changes in this release, but unfortunately it turned out that there are some. We're revisiting our [release strategy](https://github.com/storybookjs/storybook/blob/master/RELEASES.md) to follow semver more strictly.
Also read on if you're using `addon-knobs`: we advise an update to your code for efficiency's sake.

### `babel-core` is now a peer dependency ([#2494](https://github.com/storybookjs/storybook/pull/2494))

This affects you if you don't use babel in your project. You may need to add `babel-core` as dev dependency:

```sh
yarn add babel-core --dev
```

This was done to support different major versions of babel.

### Base webpack config now contains vital plugins ([#1775](https://github.com/storybookjs/storybook/pull/1775))

This affects you if you use custom webpack config in [Full Control Mode](https://storybook.js.org/configurations/custom-webpack-config/#full-control-mode) while not preserving the plugins from `storybookBaseConfig`. Before `3.3`, preserving them was just a recommendation, but now it [became](https://github.com/storybookjs/storybook/pull/2578) a requirement.

### Refactored Knobs

Knobs users: there was a bug in 3.2.x where using the knobs addon imported all framework runtimes (e.g. React and Vue). To fix the problem, we [refactored knobs](https://github.com/storybookjs/storybook/pull/1832). Switching to the new style is easy:

In the case of React or React-Native, import knobs like this:

```js
import { withKnobs, text, boolean, number } from '@storybook/addon-knobs/react';
```

In the case of Vue: `import { ... } from '@storybook/addon-knobs/vue';`

In the case of Angular: `import { ... } from '@storybook/addon-knobs/angular';`

## From version 3.1.x to 3.2.x

**NOTE:** technically this is a breaking change, but only if you use TypeScript. Sorry people!

### Moved TypeScript addons definitions

TypeScript users: we've moved the rest of our addons type definitions into [DefinitelyTyped](http://definitelytyped.org/). Starting in 3.2.0 make sure to use the right addons types:

```sh
yarn add @types/storybook__addon-notes @types/storybook__addon-options @types/storybook__addon-knobs @types/storybook__addon-links --dev
```

See also [TypeScript definitions in 3.1.x](#moved-typescript-definitions).

### Updated Addons API

We're in the process of upgrading our addons APIs. As a first step, we've upgraded the Info and Notes addons. The old API will still work with your existing projects but will be deprecated soon and removed in Storybook 4.0.

Here's an example of using Notes and Info in 3.2 with the new API.

```js
storiesOf('composition', module).add(
  'new addons api',
  withInfo('see Notes panel for composition info')(
    withNotes({ text: 'Composition: Info(Notes())' })(context => (
      <MyComponent name={context.story} />
    ))
  )
);
```

It's not beautiful, but we'll be adding a more convenient/idiomatic way of using these [withX primitives](https://gist.github.com/shilman/792dc25550daa9c2bf37238f4ef7a398) in Storybook 3.3.

## From version 3.0.x to 3.1.x

**NOTE:** technically this is a breaking change and should be a 4.0.0 release according to semver. However, we're still figuring things out and didn't think this change necessitated a major release. Please bear with us!

### Moved TypeScript definitions

TypeScript users: we are in the process of moving our typescript definitions into [DefinitelyTyped](http://definitelytyped.org/). If you're using TypeScript, starting in 3.1.0 you need to make sure your type definitions are installed:

```sh
yarn add @types/node @types/react @types/storybook__react --dev
```

### Deprecated head.html

We have deprecated the use of `head.html` for including scripts/styles/etc. into stories, though it will still work with a warning.

Now we use:

- `preview-head.html` for including extra content into the preview pane.
- `manager-head.html` for including extra content into the manager window.

[Read our docs](https://storybook.js.org/configurations/add-custom-head-tags/) for more details.

## From version 2.x.x to 3.x.x

This major release is mainly an internal restructuring.
Upgrading requires work on behalf of users, this was unavoidable.
We're sorry if this inconveniences you, we have tried via this document and provided tools to make the process as easy as possible.

### Webpack upgrade

Storybook will now use webpack 2 (and only webpack 2).
If you are using a custom `webpack.config.js` you need to change this to be compatible.
You can find the guide to upgrading your webpack config [on webpack.js.org](https://webpack.js.org/guides/migrating/).

### Packages renaming

All our packages have been renamed and published to npm as version 3.0.0 under the `@storybook` namespace.

To update your app to use the new package names, you can use the cli:

```bash
npx -p @storybook/cli sb init
```

**Details**

If the above doesn't work, or you want to make the changes manually, the details are below:

> We have adopted the same versioning strategy that has been adopted by babel, jest and apollo.
> It's a strategy best suited for ecosystem type tools, which consist of many separately installable features / packages.
> We think this describes storybook pretty well.

The new package names are:

| old                                          | new                              |
| -------------------------------------------- | -------------------------------- |
| `getstorybook`                               | `@storybook/cli`                 |
| `@kadira/getstorybook`                       | `@storybook/cli`                 |
|                                              |                                  |
| `@kadira/storybook`                          | `@storybook/react`               |
| `@kadira/react-storybook`                    | `@storybook/react`               |
| `@kadira/react-native-storybook`             | `@storybook/react-native`        |
|                                              |                                  |
| `storyshots`                                 | `@storybook/addon-storyshots`    |
| `@kadira/storyshots`                         | `@storybook/addon-storyshots`    |
|                                              |                                  |
| `@kadira/storybook-ui`                       | `@storybook/ui`                  |
| `@kadira/storybook-addons`                   | `@storybook/addons`              |
| `@kadira/storybook-channels`                 | `@storybook/channels`            |
| `@kadira/storybook-channel-postmsg`          | `@storybook/channel-postmessage` |
| `@kadira/storybook-channel-websocket`        | `@storybook/channel-websocket`   |
|                                              |                                  |
| `@kadira/storybook-addon-actions`            | `@storybook/addon-actions`       |
| `@kadira/storybook-addon-links`              | `@storybook/addon-links`         |
| `@kadira/storybook-addon-info`               | `@storybook/addon-info`          |
| `@kadira/storybook-addon-knobs`              | `@storybook/addon-knobs`         |
| `@kadira/storybook-addon-notes`              | `@storybook/addon-notes`         |
| `@kadira/storybook-addon-options`            | `@storybook/addon-options`       |
| `@kadira/storybook-addon-graphql`            | `@storybook/addon-graphql`       |
| `@kadira/react-storybook-decorator-centered` | `@storybook/addon-centered`      |

If your codebase is small, it's probably doable to just replace them by hand. (in your codebase and in `package.json`).

But if you have a lot of occurrences in your codebase, you can use a [codemod we created](./lib/codemod) for you.

> A codemod makes automatic changed to your app's code.

You have to change your `package.json`, prune old and install new dependencies by hand.

`npm prune` will remove all dependencies from `node_modules` which are no longer referenced in `package.json`.

### Deprecated embedded addons

We used to ship 2 addons with every single installation of storybook: `actions` and `links`. But in practice not everyone is using them, so we decided to deprecate this and in the future, they will be completely removed. If you use `@storybook/react/addons` you will get a deprecation warning.

If you **are** using these addons, migrating is simple:

- add the addons you use to your `package.json`.
- update your code:
  change `addons.js` like so:
  ```js
  import '@storybook/addon-actions/register';
  import '@storybook/addon-links/register';
  ```
  change `x.story.js` like so:
  ```js
  import React from 'react';
  import { storiesOf } from '@storybook/react';
  import { action } from '@storybook/addon-actions';
  import { linkTo } from '@storybook/addon-links';
  ```