typescript: Cannot find module 'tslib'

[benfoxall]

Description

When importing @mcap/nodejs (and other packages), I'm getting an error Cannot find module 'tslib'.

• Version: v22.10.0
• Platform: macOS

Steps To Reproduce

Create a minimal package.json:

{
  "dependencies": {
    "@mcap/nodejs": "^1.0.1"
  }
}

Install dependencies and import module

npm install
node -e "require('@mcap/nodejs')"

Expected Behavior

😎

Actual Behavior

node -e "require('@mcap/nodejs')"
node:internal/modules/cjs/loader:1252
  throw err;
  ^

Error: Cannot find module 'tslib'
Require stack:
- /Users/ben/tmp/mcap/node_modules/@mcap/nodejs/dist/cjs/src/index.js
- /Users/ben/tmp/mcap/[eval]
    at Function._resolveFilename (node:internal/modules/cjs/loader:1249:15)
    at Function._load (node:internal/modules/cjs/loader:1075:27)
    at TracingChannel.traceSync (node:diagnostics_channel:315:14)
    at wrapModuleLoad (node:internal/modules/cjs/loader:218:24)
    at Module.require (node:internal/modules/cjs/loader:1340:12)
    at require (node:internal/modules/helpers:141:16)
    at Object.<anonymous> (/Users/ben/tmp/mcap/node_modules/@mcap/nodejs/dist/cjs/src/index.js:3:17)
    at Module._compile (node:internal/modules/cjs/loader:1546:14)
    at Object..js (node:internal/modules/cjs/loader:1689:10)
    at Module.load (node:internal/modules/cjs/loader:1318:32) {
  code: 'MODULE_NOT_FOUND',
  requireStack: [
    '/Users/ben/tmp/mcap/node_modules/@mcap/nodejs/dist/cjs/src/index.js',
    '/Users/ben/tmp/mcap/[eval]'
  ]
}

Node.js v22.10.0

---

Additional information

The contents of node_modules/@mcap/nodejs/dist/cjs/src/index.js imports tslib for the __exportStar helper.

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
const tslib_1 = require("tslib");
tslib_1.__exportStar(require("./FileHandleReadable"), exports);
tslib_1.__exportStar(require("./FileHandleWritable"), exports);
//# sourceMappingURL=index.js.map

This looks like it's been added by the importHelpers option, which is present in the base foxglove/tsconfig.

It'd be great if tslib was a dependency, or the helpers were inlined?

Workaround

Installing tslib separately will resolve this issue.

npm install tslib

[linear]

FG-9278 [typescript] Cannot find module 'tslib'

[jtbandes]

🤔 you might be right that there's a missing dependency. However, @mcap/core does declare a dependency on tslib, so I'd expect things to work if you also have @mcap/core installed:

mcap/typescript/core/package.json

Line 60 in b304f28

"tslib": "^2.5.0"

[benfoxall]

@jtbandes oh yep that might help. I think in my case I may have had an additional monorepo/package-hoisting issue where core/nodejs were separated 😬