Method parseYAMLConfig

repl/evaluator.go:917–1000

(conf []byte)

var trailerRegexp = regexp.MustCompile("# REPL Bindings:")

func (e *Evaluator) parseYAMLConfig(conf []byte) (string, error) {
	yamlSrc := conf
	var replSrc []byte

	pos := trailerRegexp.FindIndex(conf)
	if len(pos) == 2 {
		yamlSrc = conf[0:pos[0]]
		replSrc = conf[pos[1]:]
	}

	var c env.Config
	if err := yaml.Unmarshal(yamlSrc, &c); err != nil {
		return "", fmt.Errorf("configure (yaml): %w", err)
	}

	s := string(replSrc)

	lines := strings.Split(s, "\n")

	// A little unfortunate, but we need to apply option commands manually
	// before the yaml environment. This is mainly because the yaml doesn't
	// describe how to lookup extension types (e.g. load_descriptors).
	updated, _ := NewEvaluator()

	var cmds []Cmder
	var sb strings.Builder
	for _, line := range lines {
		if !strings.HasPrefix(line, "# ") {
			continue
		}
		norm := strings.TrimPrefix(line, "# ")
		if strings.HasSuffix(norm, "\\") {
			norm = strings.TrimSuffix(norm, "\\")
			sb.WriteString(norm)
			sb.WriteString("\n")
			continue
		}
		sb.WriteString(norm)
		cmd := sb.String()
		sb.Reset()
		pCmd, err := Parse(cmd)
		if err != nil {
			return "", fmt.Errorf("configure: invalid REPL command: %w", err)
		}
		switch pCmd.(type) {
		case *letFnCmd, *letVarCmd:
			cmds = append(cmds, pCmd)
			continue
		}
		_, exit, err := updated.Process(pCmd)

		if exit {
			return "", errors.New("configure: config triggered an exit")
		}
		if err != nil {
			return "", fmt.Errorf("configure: failed to process option %w", err)
		}
	}