fix: correctly detect the active Node js version during headless installation

[dy-dx]

This is a proof of concept for fixing #5266.

When pnpm is bundled with node.js (via standalone installer), and engine-strict=true, pnpm falls back to using the bundled node.js.

pnpm properly detects the system node.js version when installing new packages, but not when doing headless installs (i.e. when the lockfile is up to date).

I think the issue is the extendOptions function:

pnpm/pkg-manager/core/src/install/index.ts

Line 234 in e71ca75

const opts = extendOptions(maybeOpts)

It sets options.nodeVersion = process.version, i.e. whatever node is bundled with pnpm.

This doesn't seem to matter during the code path for non-headless installations.
But during headless installations, it prevents pnpm from checking the system Node.js version when checking package compatibility.

[welcome]

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[zkochan]

But the same code is present here:

pnpm/config/package-is-installable/src/index.ts

Line 89 in e71ca75

node: options.nodeVersion ?? getSystemNodeVersion(),

So does this change actually make any difference?

So you just need to replace process.version with opts.nodeVersion. No need to run getSystemNodeVersion

But we also need to check where and how is opts.nodeVersion set.

[zkochan]

This should be enough

Suggested change

	nodeVersion: opts.nodeVersion ?? getSystemNodeVersion(),
	nodeVersion: opts.nodeVersion,

[zkochan]

The issue is that we pass process.version. getSystemNodeVersion will be used anyway inside package-is-installable.

[welcome]

Congrats on merging your first pull request! 🎉🎉🎉

[dy-dx]

So you just need to replace process.version with opts.nodeVersion. No need to run getSystemNodeVersion

@zkochan yes I agree, I actually tried that first and I can confirm that it also solves the issue. But I wasn't sure if the resulting typing changes were going to be problematic or not.

Thanks for the quick response!