fix: handle "main": false in package.json without crashing

[clanzhang]

🔗 Linked issue

Fixes #209

🧭 Context

Some packages set "main": false in their package.json — [email protected] and [email protected] do this (both come in through get-intrinsic). They're exports-only packages.

analyzePackageModuleType() assumed main was always a string and called pkgJson.main?.endsWith(...) on it. Since false is not a string, this throws: TypeError: pkgJson.main?.endsWith is not a function The whole inspector goes down — UI shows "Failed to Connect to the Backend".

📚 Description

Normalize main to string | undefined at the top of the function:

const main = typeof pkgJson.main === 'string' ? pkgJson.main : undefined 

Then use the local variable everywhere. Four call sites changed from pkgJson.main?.endsWith to main?.endsWith.

Files changed:

1. packages/node-modules-tools/src/analyze-esm.ts --- the fix
2. packages/node-modules-tools/src/analyze-esm.test.ts --- test case with
   main: false

[pkg-pr-new]

Open in StackBlitz

npm i https://pkg.pr.new/node-modules-inspector@210

npm i https://pkg.pr.new/node-modules-tools@210

commit: 5808c80