code: function() {
      this.setHelpUrl(Blockly.Msg.TEXT_TEXT_HELPURL);
      this.setColour(Blockly.Blocks.texts.HUE);
      this.appendDummyInput()
          .appendField(this.newQuote_(true))
          .appendField(new Blockly.FieldTextInput(''), 'TEXT')
          .appendField(this.newQuote_(false));
      this.setOutput(true, 'String');
      // Assign 'this' to a variable for use in the tooltip closure below.
      var thisBlock = this;
      // Text block is trivial.  Use tooltip of parent block if it exists.
      this.setTooltip(function() {
        var parent = thisBlock.getParent();
        return (parent && parent.tooltip) || Blockly.Msg.TEXT_TEXT_TOOLTIP;
      });
    }
docs: Block for text value.
  @this Blockly.Block