requirements = LoadModFile(ctx)
	return commitRequirements(ctx, opts)
}

var errNoChange = errors.New("no update needed")

// UpdateGoModFromReqs returns a modified go.mod file using the current
// requirements. It does not commit these changes to disk.
func UpdateGoModFromReqs(ctx context.Context, opts WriteOpts) (before, after []byte, modFile *modfile.File, err error) {

				keep[m] = true
			}
		}

		if opts.TidyDiff {
			cfg.BuildMod = "readonly"
			loaded = ld
			requirements = loaded.requirements
			currentGoMod, updatedGoMod, _, err := UpdateGoModFromReqs(ctx, WriteOpts{})
			if err != nil {
				base.Fatal(err)
			}
			goModDiff := diff.Diff("current/go.mod", currentGoMod, "tidy/go.mod", updatedGoMod)

			modfetch.TrimGoSum(keep)