Can't build S2 with Storybook, Webpack, and Babel

[loganzartman]

Provide a general summary of the issue here

I'm having trouble building Storybook with the S2 style macro. Specifically, I'm having issues when using @storybook/addon-webpack5-compiler-babel, but NOT with @storybook/addon-webpack5-compiler-swc. When running storybook dev, I get an error like this:

[webpack-dev-middleware] wait until bundle finished
ERROR in ./stories/S2Test.jsx
Module build failed (from ./node_modules/.pnpm/babel-loader@9.2.1_@babel+core@7.26.7_webpack@5.97.1_@swc+core@1.10.14_@swc+helpers@0.5.15__esbuild@0.24.2_/node_modules/babel-loader/lib/index.js):
Error: .inputSourceMap must be a boolean, object, or undefined
    at Object.loadPartialConfigAsync (/Users/logan/storybook-react-webpack-s2/node_modules/.pnpm/@babel+core@7.26.7/node_modules/@babel/core/src/config/index.ts:45:61)
    at Object.loader (/Users/logan/storybook-react-webpack-s2/node_modules/.pnpm/babel-loader@9.2.1_@babel+core@7.26.7_webpack@5.97.1_@swc+core@1.10.14_@swc+helpers@0.5.15__esbuild@0.24.2_/node_modules/babel-loader/lib/index.js:116:30)
    at Object.<anonymous> (/Users/logan/storybook-react-webpack-s2/node_modules/.pnpm/babel-loader@9.2.1_@babel+core@7.26.7_webpack@5.97.1_@swc+core@1.10.14_@swc+helpers@0.5.15__esbuild@0.24.2_/node_modules/babel-loader/lib/index.js:39:12)
 @ ./stories/S2Test.stories.js 1:0-34 4:13-19
 @ ./stories/ lazy ^\.\/.*$ include: (?%21.*node_modules)(?:\/stories(?:\/(?%21\.)(?:(?:(?%21(?:^%7C\/)\.).)*?)\/%7C\/%7C$)(?%21\.)(?=.)[^/]*?\.stories\.(js%7Cjsx%7Cmjs%7Cts%7Ctsx))$ chunkName: [request] namespace object ./S2Test.stories.js ./S2Test.stories
 @ ./storybook-stories.js 23:11-27:5
 @ ./storybook-config-entry.js 6:0-50 17:31-39 24:2-27:4 24:58-27:3 26:31-39

preview compiled with 1 error
=> Failed to build the preview

I think this is related to unplugin-parcel-macros, because without it I don't get this error (but I can't use the style macro).

I created a minimal repro here: https://github.com/loganzartman/storybook-react-webpack-s2
and the minimal diff to break it is here: loganzartman/storybook-react-webpack-s2@82b1e13

I stepped into the debugger a bit, and I see that inputSourceMap seems to contain a JSON string instead of a JS object:

🤔 Expected Behavior?

Successful Storybook build of code with S2 style macro, when using Webpack + Babel

😯 Current Behavior

Error containing .inputSourceMap must be a boolean, object, or undefined

💁 Possible Solution

No response

🔦 Context

No response

🖥️ Steps to Reproduce

1. git clone https://github.com/loganzartman/storybook-react-webpack-s2
2. pnpm i
3. pnpm storybook

Version

@react-spectrum/s2@0.6.0

What browsers are you seeing the problem on?

Chrome

If other, please specify.

No response

What operating system are you using?

Mac OS

🧢 Your Company/Team

Adobe/Home

🕷 Tracking Issue

No response