Method _addMessage

packages/compiler/src/i18n/extractor_merger.ts:419–434

(ast: html.Node[], msgMeta?: string)

  // add a translatable message
  private _addMessage(ast: html.Node[], msgMeta?: string): i18n.Message | null {
    if (
      ast.length == 0 ||
      this._isEmptyAttributeValue(ast) ||
      this._isPlaceholderOnlyAttributeValue(ast) ||
      this._isPlaceholderOnlyMessage(ast)
    ) {
      // Do not create empty messages
      return null;
    }

    const {meaning, description, id} = _parseMessageMeta(msgMeta);
    const message = this._createI18nMessage(ast, meaning, description, id);
    this._messages.push(message);
    return message;
  }

  // Check for cases like `<div i18n-title title="">`.
  private _isEmptyAttributeValue(ast: html.Node[]): boolean {