Handling Fields that Reference Variables

Problem statement

Currently there is a referencesVariables function that is supposed to tell blockly whether a field references variables. But the way blockly gets the variables after it knows they are being referenced is pretty inflexible.

Blockly.Block.prototype.getVars = function() {
  var vars = [];
  for (var i = 0, input; input = this.inputList[i]; i++) {
    for (var j = 0, field; field = input.fieldRow[j]; j++) {
      if (field.referencesVariables()) {
        vars.push(field.getValue());
      }
    }
  }
  return vars;
};

This expects the value of the field to be a variable name, but this is not necessarily true of custom fields. The value could be two variable names, or a variable name and a const, really anything.

Proposals

1. Add a getReferencedVariables() function that fields could override instead of referencesVariables().
2. Remove referencesVariables(), instead add a type property to fields, and then have getVars check if the field is a variable field before calling getValue(). This means only variable fields would be allowed to reference variables.

Additional Information

N/A

[BeksOmega]

Could I work on this ?

Yeah definitely! Once one of the blockly people gives a reply about which proposal they like.

[RoboErikG]

@abhinavsagar feel free to update the jsdoc (or let us know if it’s affecting you in some way). =)