[code-infra] Migrate to babel 8

.circleci/config.yml

@@ -1,6 +1,6 @@
 version: 2.1
 orbs:
-  code-infra: https://raw.githubusercontent.com/mui/mui-public/c6471a4fe98cb2e52efe7397ff8362569f2ddada/.circleci/orbs/code-infra.yml
+  code-infra: https://raw.githubusercontent.com/mui/mui-public/08eb27e8b00569d564ede0903e59d0129bbe6b9a/.circleci/orbs/code-infra.yml
 
 parameters:
   workflow:

babel.config.mjs

@@ -79,14 +79,17 @@ export default function getBabelConfig(api) {
     ...baseConfig,
     plugins: basePlugins,
     // `@babel/plugin-transform-react-constant-elements` hoists static JSX — prod-only optimization.
-    overrides: isProductionBuild
-      ? [
-          {
-            exclude: /\.test\.(m?js|ts|tsx)$/,
-            plugins: ['@babel/plugin-transform-react-constant-elements'],
-          },
-        ]
-      : [],
+    overrides: [
+      ...(baseConfig.overrides ?? []),
+      ...(isProductionBuild
+        ? [
+            {
+              exclude: /\.test\.(m?js|ts|tsx)$/,
+              plugins: ['@babel/plugin-transform-react-constant-elements'],
+            },
+          ]
+        : []),
+    ],
     env: {
       development: {
         plugins: [

package.json

@@ -82,9 +82,9 @@
   },
   "devDependencies": {
     "@arethetypeswrong/cli": "0.18.5",
-    "@babel/core": "7.29.7",
-    "@babel/node": "7.29.7",
-    "@babel/plugin-transform-react-constant-elements": "7.29.7",
+    "@babel/core": "8.0.5",
+    "@babel/node": "8.0.1",
+    "@babel/plugin-transform-react-constant-elements": "8.0.1",
     "@eslint/compat": "2.1.1",
     "@mui/internal-babel-plugin-minify-errors": "2.0.8-canary.31",
     "@mui/internal-bundle-size-checker": "1.0.9-canary.92",

packages/mui-material/src/styles/createTheme.ts

@@ -1,10 +1,11 @@
-import createPalette, { PaletteOptions } from './createPalette';
+import createPalette from './createPalette';
+import type { PaletteOptions } from './createPalette';
 import {
   resolveFocusVisible,
   mergeFocusVisibleInput,
   isResolvedFocusVisible,
 } from './focusVisible';
-import { ColorSystemOptions } from './createThemeFoundation';
+import { type ColorSystemOptions } from './createThemeFoundation';
 import createThemeWithVars, {
   CssVarsThemeOptions,
   ColorSystem,

packages/mui-material/src/styles/overrides.ts

@@ -1,4 +1,4 @@
-import { CSSObject, CSSInterpolation, Interpolation } from '@mui/system';
+import { type CSSObject, type CSSInterpolation, type Interpolation } from '@mui/system';
 import { PopperClassKey } from '../Popper';
 import { ComponentsPropsList } from './props';
 import { AccordionActionsClassKey } from '../AccordionActions';

packages/mui-material/src/styles/variants.ts

@@ -1,4 +1,4 @@
-import { Interpolation } from '@mui/system';
+import { type Interpolation } from '@mui/system';
 import { ComponentsPropsList } from './props';
 
 export type ComponentsVariants<Theme = unknown> = {

packages/mui-material/src/utils/memoTheme.ts

@@ -1,5 +1,5 @@
 import { unstable_memoTheme } from '@mui/system';
-import { Theme } from '../styles/createTheme';
+import { type Theme } from '../styles/createTheme';
 
 const memoTheme: typeof unstable_memoTheme<Theme> = unstable_memoTheme<Theme>;
 

packages/mui-material/src/zero-styled/index.tsx

@@ -1,8 +1,8 @@
-import { Interpolation } from '@mui/system';
+import { type Interpolation } from '@mui/system';
 import { extendSxProp } from '@mui/system/styleFunctionSx';
-import { Theme } from '../styles/createTheme';
+import { type Theme } from '../styles/createTheme';
 import useTheme from '../styles/useTheme';
-import GlobalStyles, { GlobalStylesProps } from '../GlobalStyles';
+import GlobalStyles, { type GlobalStylesProps } from '../GlobalStyles';
 
 export { css, keyframes } from '@mui/system';
 

pnpm-workspace.yaml

@@ -9,7 +9,10 @@ packages:
 engineStrict: true
 enablePrePostScripts: true
 updateNotifier: false
-blockExoticSubdeps: true
+# TEMP: disabled for pkg.pr.new testing of mui/mui-public#1875 (@mui/internal-code-infra
+# pulls in its own workspace deps as pkg.pr.new URL subdeps). Restore to true once the
+# overrides above are removed.
+blockExoticSubdeps: false
 minimumReleaseAge: 4320
 minimumReleaseAgeExclude:
   - '@mui/*'
@@ -43,6 +46,15 @@ catalogs:
     '@emotion/styled': '^11.14.1'
 
 overrides:
+  # TEMP: pin to mui-public#1875's pkg.pr.new build until it merges and publishes a real
+  # Babel-8 @mui/internal-code-infra. Remove this whole block (and blockExoticSubdeps below)
+  # once that lands and this repo's own @mui/internal-* versions are bumped normally.
+  '@mui/internal-code-infra': 'https://pkg.pr.new/mui/mui-public/@mui/internal-code-infra@08eb27e8b'
+  '@mui/internal-netlify-cache': 'https://pkg.pr.new/mui/mui-public/@mui/internal-netlify-cache@08eb27e8b'
+  '@mui/internal-test-utils': 'https://pkg.pr.new/mui/mui-public/@mui/internal-test-utils@08eb27e8b'
+  '@mui/internal-babel-plugin-display-name': 'https://pkg.pr.new/mui/mui-public/@mui/internal-babel-plugin-display-name@08eb27e8b'
+  '@mui/internal-babel-plugin-minify-errors': 'https://pkg.pr.new/mui/mui-public/@mui/internal-babel-plugin-minify-errors@08eb27e8b'
+  '@mui/internal-babel-plugin-resolve-imports': 'https://pkg.pr.new/mui/mui-public/@mui/internal-babel-plugin-resolve-imports@08eb27e8b'
   # Both were bundled twice in the docs build
   'docs>stylis': '4.2.0'
   'docs>react-is': '19.3.0'