if len(modFiles) != 1 {
			panic(fmt.Errorf("requirementsFromModFiles called with %v modfiles outside workspace mode", len(modFiles)))
		}
		modFile := modFiles[0]
		roots, direct = rootsFromModFile(MainModules.mustGetSingleMainModule(), modFile, withToolchainRoot)
	}

	gover.ModSort(roots)
	rs := newRequirements(pruning, roots, direct)
	return rs
}

type addToolchainRoot bool

			// dependencies.
			vendorMod := module.Version{Path: "vendor/modules.txt", Version: ""}
			if inWorkspaceMode() {
				for _, m := range MainModules.Versions() {
					reqs, _ := rootsFromModFile(m, MainModules.ModFile(m), omitToolchainRoot)
					mg.g.Require(m, append(reqs, vendorMod))
				}
				mg.g.Require(vendorMod, vendorList)

			} else {
				mainModule := MainModules.mustGetSingleMainModule()