Uncaught TypeError: Cannot read properties of undefined (reading 'DEV')

[kling90]

Describe the bug

After updating to version 5.2.10 we get the following error:

Uncaught TypeError: Cannot read properties of undefined (reading 'DEV')

I suppose this is because of the upgrade of esm-env because it works as expected when we override this dependecy and downgrade it to version 1.0.0

"overrides": {
  "esm-env": "1.0.0"
},

We are bundling with Rollup and not Vite.

Reproduction

Not sure how to provide a proper reporoduction without recreating our build environment to work outside the CMS we use.

Logs

No response

System Info

System:
    OS: Windows 11 10.0.22621
    CPU: (16) x64 12th Gen Intel(R) Core(TM) i7-1260P
    Memory: 3.21 GB / 31.71 GB
  Binaries:
    Node: 22.11.0 - ~\AppData\Local\Volta\tools\image\node\22.11.0\node.EXE
    Yarn: 1.22.22 - ~\AppData\Local\Volta\tools\image\yarn\1.22.22\bin\yarn.CMD
    npm: 10.9.0 - ~\AppData\Local\Volta\tools\image\npm\10.9.0\bin\npm.CMD
    pnpm: 9.12.3 - ~\AppData\Local\Volta\tools\image\pnpm\9.12.3\bin\pnpm.CMD
  Browsers:
    Edge: Chromium (129.0.2792.89)
    Internet Explorer: 11.0.22621.3527
  npmPackages:
    svelte: 5.2.10 => 5.2.10

Severity

blocking all usage of svelte

[Conduitry]

I also ran into something similar with my homegrown build process. What worked for me was - in addition to setting a development condition when resolving import maps in dev builds - to start setting a production condition in prod builds.

Alternatively, you could probably override the transitive esm-env dependency to version 1.1.x and prevent it from upgrading to 1.2.0, which is where the code in question is coming from.

[kling90]

Yeah, I noticed that esm-env had different exports and that the default one for development was imported for me.
Added 'development' or 'production' to exportConditions for @rollup/plugin-node-resolve and it works now.

nodeResolve({
    mainFields: ['module', 'main'],
    extensions: ['.js', '.mjs', '.json', '.svelte'],  
    exportConditions: ['svelte', (debug ? 'development' : 'production')],
    dedupe(importee) {
      return importee === 'svelte' || importee.startsWith('svelte/');
    },
  })