Unable to build with 4.1.392: error TS2304: Build:Cannot find name 'PromiseWithResolvers'

[Welchen]

Attach (recommended) or Link to PDF file here:

Configuration:

• Visual Studio 2022 17.9.6
• .NET 8 Blazor
• PDF.js version: 4.1.392
• Node 20.12.2

Updated to the newest version and unable to build with Typescript. Something changed between 4.0 and 4.1. Are there new dependencies needed?

[andreymyssak]

Small investigation from my side:
I've tested it on Node v20.11.1. The issue does not occur with pdfjs-dist v4.0.379. It only happens in v4.1.392, and I think this started after the changes made in #17854.

The method Promise.withResolvers is not yet supported by Node if you try to run it on the server side - https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise/withResolvers#browser_compatibility

[Welchen]

Small investigation from my side: I've tested it on Node v20.11.1. The issue does not occur with pdfjs-dist v4.0.379. It only happens in v4.1.392, and I think this started after the changes made in #17854.

The method Promise.withResolvers is not yet supported by Node if you try to run it on the server side - https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise/withResolvers#browser_compatibility

Updated my post to include my node version. Using 20.12.2 (updated today after the issue started) and still seeing the issue as well.

I have not tried a non-LTS version.

When we revert back to v4.0.379 we also do not see the issue.

Looks like we are both seeing the same thing.

[Snuffleupagus]

Please use the legacy-build, note https://github.com/mozilla/pdf.js/wiki/Frequently-Asked-Questions#faq-support

[tamuratak]

This issue seems related to TypeScript files under types/src/ bundled with pdfjs-dist. We can see PromiseWithResolvers at types/src/display/api.d.ts

• https://cdn.jsdelivr.net/npm/pdfjs-dist@4.1.392/types/src/display/api.d.ts

The PromiseWithResolvers is a recently added type:

• https://github.com/microsoft/TypeScript/blob/main/src/lib/esnext.promise.d.ts

Users must set "lib": ["ESNext.Promise"] in their tsconfig.json to compile their project without errors.

A workaround on the users' side is to set "skipLibCheck": true in their tsconfig.json.

A fix on PDF.js' side would be to set "target": "ES2020" instead of ESNext in tsconfig.json. Then, the usage of PromiseWithResolvers can be avoided in the generated type files.

• pdf.js/tsconfig.json

  Line 3 in e78ce74

  "target": "ESNext",

[acurrieclark]

While possibly not a long term fix with other potential breaking changes coming for node, there is a polyfill available for Promise.withResolvers() as part of core-js which is working nicely for me.