feat(ui): migrate jest from babel-jest to @swc/jest

.github/CODEOWNERS

@@ -172,7 +172,6 @@ pyproject.toml                                           @getsentry/owners-pytho
 vercel.json                                              @getsentry/owners-js-build
 /.github/workflows/frontend.yml                          @getsentry/owners-js-build
 /.github/file-filters.yml                                @getsentry/owners-js-build
-babel.config.*                                           @getsentry/owners-js-build
 build-utils/                                             @getsentry/owners-js-build
 eslint.config.ts                                         @getsentry/owners-js-build
 jest-balance.json                                        @getsentry/owners-js-build

.github/dependabot.yml

@@ -15,9 +15,9 @@ updates:
     # https://docs.github.com/en/code-security/dependabot/dependabot-version-updates/configuration-options-for-the-dependabot.yml-file#groups
     groups:
       # The name of the group, it will be used in PR titles and branch
-      babel-dependencies:
+      swc-dependencies:
         patterns:
-          - '@babel/*'
+          - '@swc/*'
       sentry-dependencies:
         patterns:
           - '@sentry/core'

.github/workflows/frontend.yml

@@ -131,6 +131,17 @@ jobs:
 
       - uses: ./.github/actions/setup-node-pnpm
 
+      - name: jest transform cache
+        uses: actions/cache@1bd1e32a3bdc45362d1e726936510720a7c30a57 # v4.2.0
+        with:
+          path: |
+            .cache/jest
+            ~/.cache/swc
+          key: jest-cache-${{ runner.os }}-${{ hashFiles('pnpm-lock.yaml', 'jest.config.ts') }}-${{ matrix.instance }}
+          restore-keys: |
+            jest-cache-${{ runner.os }}-${{ hashFiles('pnpm-lock.yaml', 'jest.config.ts') }}-
+            jest-cache-${{ runner.os }}-
+
       - name: Download jest-balance.json
         id: download-artifact
         uses: dawidd6/action-download-artifact@ac66b43f0e6a346234dd65d4d0c8fbb31cb316e5 # v11

.vercelignore

@@ -8,7 +8,6 @@
 !src/sentry/locale/**
 !build-utils
 !build-utils/**
-!babel.config.js
 !jest.config.js
 !now.json
 !package.json

eslint.config.ts

@@ -757,7 +757,7 @@ export default typescript.config([
     plugins: {'@emotion': emotion},
     rules: {
       '@emotion/import-from-emotion': 'off', // Not needed, in v11 we import from @emotion/react
-      '@emotion/jsx-import': 'off', // Not needed, handled by babel
+      '@emotion/jsx-import': 'off', // Not needed, handled by swc
       '@emotion/no-vanilla': 'error',
       '@emotion/pkg-renaming': 'off', // Not needed, we have migrated to v11 and the old package names cannot be used anymore
       '@emotion/styled-import': 'error',

jest.config.snapshots.ts

@@ -1,43 +1,47 @@
-import type {TransformOptions} from '@babel/core';
 import type {Config} from '@jest/types';
+import type {Options as SwcOptions} from '@swc/core';
 
-const babelConfig: TransformOptions = {
-  presets: [
-    [
-      '@babel/preset-react',
-      {
+const swcConfig: SwcOptions = {
+  isModule: true,
+  module: {
+    type: 'commonjs',
+  },
+  sourceMaps: 'inline',
+  jsc: {
+    target: 'esnext',
+    parser: {
+      syntax: 'typescript',
+      tsx: true,
+      dynamicImport: true,
+    },
+    transform: {
+      react: {
         runtime: 'automatic',
         importSource: '@emotion/react',
       },
-    ],
-    [
-      '@babel/preset-env',
-      {
-        useBuiltIns: 'usage',
-        corejs: '3.41',
-        targets: {
-          node: 'current',
-        },
-      },
-    ],
-    ['@babel/preset-typescript', {allowDeclareFields: true, onlyRemoveTypeImports: true}],
-  ],
-  plugins: [
-    [
-      '@emotion/babel-plugin',
-      {
-        sourceMap: false,
-      },
-    ],
-  ],
+    },
+    experimental: {
+      plugins: [
+        ['@swc-contrib/mut-cjs-exports', {}],
+        [
+          '@swc/plugin-emotion',
+          {
+            sourceMap: false,
+            autoLabel: 'never',
+          },
+        ],
+      ],
+    },
+  },
 };
 
 /**
- * ESM packages that need to be transformed by babel-jest.
+ * ESM packages that need to be transformed.
  */
 const ESM_NODE_MODULES = ['screenfull', 'cbor2', 'nuqs', 'color'];
 
 const config: Config.InitialOptions = {
+  cacheDirectory: '.cache/jest-snapshots',
   // testEnvironment and testMatch are the core differences between this and the main config
   testEnvironment: 'node',
   testMatch: ['<rootDir>/static/**/*.snapshots.tsx'],
@@ -63,9 +67,7 @@ const config: Config.InitialOptions = {
   },
 
   transform: {
-    '^.+\\.jsx?$': ['babel-jest', babelConfig as any],
-    '^.+\\.tsx?$': ['babel-jest', babelConfig as any],
-    '^.+\\.mjs?$': ['babel-jest', babelConfig as any],
+    '^.+\\.[mc]?[jt]sx?$': ['@swc/jest', swcConfig],
   },
   transformIgnorePatterns: [
     ESM_NODE_MODULES.length

jest.config.ts

@@ -2,39 +2,32 @@ import {execFileSync} from 'node:child_process';
 import path from 'node:path';
 import process from 'node:process';
 
-import type {TransformOptions} from '@babel/core';
 import type {Config} from '@jest/types';
+import type {Options as SwcOptions} from '@swc/core';
 
-const babelConfig: TransformOptions = {
-  presets: [
-    [
-      '@babel/preset-react',
-      {
+const swcConfig: SwcOptions = {
+  isModule: true,
+  module: {
+    type: 'commonjs',
+  },
+  sourceMaps: 'inline',
+  jsc: {
+    target: 'esnext',
+    parser: {
+      syntax: 'typescript',
+      tsx: true,
+      dynamicImport: true,
+    },
+    transform: {
+      react: {
         runtime: 'automatic',
         importSource: '@emotion/react',
       },
-    ],
-    [
-      '@babel/preset-env',
-      {
-        useBuiltIns: 'usage',
-        corejs: '3.41',
-        targets: {
-          node: 'current',
-        },
-      },
-    ],
-    // TODO: Remove allowDeclareFields when we upgrade to Babel 8
-    ['@babel/preset-typescript', {allowDeclareFields: true, onlyRemoveTypeImports: true}],
-  ],
-  plugins: [
-    [
-      '@emotion/babel-plugin',
-      {
-        sourceMap: false,
-      },
-    ],
-  ],
+    },
+    experimental: {
+      plugins: [['@swc-contrib/mut-cjs-exports', {}]],
+    },
+  },
 };
 
 const {
@@ -284,6 +277,7 @@ const ESM_NODE_MODULES = [
 
 const config: Config.InitialOptions = {
   verbose: false,
+  cacheDirectory: '.cache/jest',
   collectCoverageFrom: [
     'static/app/**/*.{js,jsx,ts,tsx}',
     '!static/app/**/*.spec.{js,jsx,ts,tsx}',
@@ -334,8 +328,7 @@ const config: Config.InitialOptions = {
     '<rootDir>/node_modules/reflux',
   ],
   transform: {
-    '^.+\\.jsx?$': ['babel-jest', babelConfig as any],
-    '^.+\\.tsx?$': ['babel-jest', babelConfig as any],
+    '^.+\\.[mc]?[jt]sx?$': ['@swc/jest', swcConfig],
     '^.+\\.pegjs?$': '<rootDir>/tests/js/jest-pegjs-transform.js',
   },
   transformIgnorePatterns: [

knip.config.ts

@@ -77,11 +77,8 @@ const config: KnipConfig = {
     'tslib', // subdependency of many packages, declare the latest version
     'buffer', // rspack.ProvidePlugin, needs better knip plugin
     'process', // rspack.ProvidePlugin, needs better knip plugin
-    '@babel/preset-env', // Still used in jest
-    '@babel/preset-react', // Still used in jest
-    '@babel/preset-typescript', // Still used in jest
-    '@emotion/babel-plugin', // Still used in jest
     'odiff-bin', // raw binary consumed by Python backend, not a JS import
+    '@swc-contrib/mut-cjs-exports', // used in jest config
   ],
   rules: {
     binaries: 'off',

package.json

@@ -52,15 +52,10 @@
   },
   "dependencies": {
     "@amplitude/analytics-browser": "^1.5.3",
-    "@babel/core": "~7.29.0",
-    "@babel/preset-env": "~7.29.0",
-    "@babel/preset-react": "^7.28.5",
-    "@babel/preset-typescript": "^7.28.5",
     "@dnd-kit/core": "^6.1.0",
     "@dnd-kit/modifiers": "7.0.0",
     "@dnd-kit/sortable": "^8.0.0",
     "@dnd-kit/utilities": "^3.2.2",
-    "@emotion/babel-plugin": "^11.13.5",
     "@emotion/cache": "^11.14.0",
     "@emotion/css": "^11.13.5",
     "@emotion/is-prop-valid": "^1.3.0",
@@ -122,7 +117,7 @@
     "@sentry/webpack-plugin": "4.6.1",
     "@stripe/react-stripe-js": "^3.9.2",
     "@stripe/stripe-js": "^5.10.0",
-    "@swc/plugin-emotion": "14.3.0",
+    "@swc/plugin-emotion": "14.8.0",
     "@tanstack/query-async-storage-persister": "5.96.0",
     "@tanstack/react-devtools": "0.9.9",
     "@tanstack/react-form": "1.28.6",
@@ -242,6 +237,9 @@
     "@sentry/jest-environment": "6.1.0",
     "@sentry/profiling-node": "10.41.0-beta.0",
     "@styled/typescript-styled-plugin": "^1.0.1",
+    "@swc-contrib/mut-cjs-exports": "14.8.0",
+    "@swc/core": "1.15.24",
+    "@swc/jest": "0.2.39",
     "@tanstack/eslint-plugin-query": "5.96.0",
     "@testing-library/dom": "10.4.1",
     "@testing-library/jest-dom": "6.9.1",
@@ -255,7 +253,6 @@
     "@typescript-eslint/utils": "8.58.0",
     "@typescript/native-preview": "7.0.0-dev.20260401.1",
     "@volar/typescript": "^2.4.28",
-    "babel-jest": "30.3.0",
     "eslint": "9.34.0",
     "eslint-config-prettier": "10.1.8",
     "eslint-import-resolver-typescript": "^3.8.3",