Core: Remove project root babel.config.js loading

MIGRATION.md

@@ -1,66 +1,69 @@
 # Migration
 
-- [Migration](#Migration)
-  - [From version 5.1.x to 5.2.x](#From-version-51x-to-52x)
-    - [Docs mode docgen](#Docs-mode-docgen)
-    - [storySort option](#storySort-option)
-  - [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)
+- [Migration](#migration)
+  - [From version 5.1.x to 5.2.x](#from-version-51x-to-52x)
+    - [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)
+    - [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)
+    - [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
 
@@ -89,6 +92,12 @@ addParameters({
 });
 ```
 
+## 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

lib/core/src/server/utils/load-custom-babel-config.js

@@ -80,10 +80,12 @@ function isBabelLoader8() {
 }
 
 export default async function(configDir, getDefaultConfig) {
-  const projectRoot = process.cwd();
+  // Between versions 5.1.0 - 5.1.9 this loaded babel.config.js from the project
+  // root, which was an unintentional breaking change. We can add back project support
+  // in 6.0.
   const babelConfig =
     loadFromPath(path.resolve(configDir, '.babelrc')) ||
-    loadFromPath(path.resolve(projectRoot, 'babel.config.js'));
+    loadFromPath(path.resolve(configDir, 'babel.config.js'));
 
   if (babelConfig) {
     // If the custom config uses babel's `extends` clause, then replace it with