// for imported packages (as in 'go mod tidy' in Go 1.17–1.20).
	skipImportModFiles bool

	work *par.Queue

	// reset on each iteration
	roots    []*loadPkg
	pkgCache *par.Cache[string, *loadPkg]
	pkgs     []*loadPkg // transitive closure of loaded packages and tests; populated in buildStacks
}

// loaderParams configure the packages loaded by, and the properties reported
// by, a loader instance.

func tidyRoots(ctx context.Context, rs *Requirements, pkgs []*loadPkg) (*Requirements, error) {
	mainModule := MainModules.mustGetSingleMainModule()
	if rs.pruning == unpruned {
		return tidyUnprunedRoots(ctx, mainModule, rs, pkgs)
	}
	return tidyPrunedRoots(ctx, mainModule, rs, pkgs)
}

func updateRoots(ctx context.Context, direct map[string]bool, rs *Requirements, pkgs []*loadPkg, add []module.Version, rootsImported bool) (*Requirements, error) {