GoPathError = "cannot set GOROOT as GOPATH"
		}
		return ""
	}
	GoPathError = fmt.Sprintf("%s is not set", env)
	return ""
}

// WithBuildXWriter returns a Context in which BuildX output is written
// to given io.Writer.
func WithBuildXWriter(ctx context.Context, xLog io.Writer) context.Context {
	return context.WithValue(ctx, buildXContextKey{}, xLog)
}

type buildXContextKey struct{}