Identify the Bug or Feature request

resolves #5152

The linked issue misdiagnoses the issue as Token.setProperty setting a value differently and not being identified as equalling the default to reset.

Actually it's only the Edit Token dialog that resets properties that way.

The lack of functions for resetting properties and determining what the default is however prevents implementing this behaviour yourself, so this patch resolves it by adding required functions.

Description of the Change

This refactors the Token functions slightly to make the property default code and property evaluator reusable, and adds javascript bindings.

Possible Drawbacks

This allows evaluating the defaults even if there is a value set, and an obscure enough campaign might hide logic in there that is usually obscured by a non-default value being present in that property.

Documentation Notes

token.resetProperty(name) Function

• Introduced in version 1.17

Returns true if the property was reset, false if it was not e.g. because you don't own it.

Usage

function fullHeal(token) {
  token.resetProperty("HP");
}

• name - The name of the property to reset.

See resetProperty() for MTScript equivalent.

token.getPropertyDefault(name) Function

• Introduced in version 1.17

Returns the text of the default value if it exists, null if it didn't or you don't own the token.

Usage

function changeHP(token, value) {
  if (value == token.getPropertyDefault("HP")) {
    token.resetProperty("HP");
  } else {
    token.setProperty("HP", value);
  }
}

• name - The name of the property to retrieve the default for.

See getPropertyDefault() for MTScript equivalent.

token.getEvaluatedPropertyDefault(name) Function

• Introduced in version 1.17

Returns the value of the default's expression, evaluated in the context of the token if it exists, null if it didn't or you don't own the token.

Usage

function changeHP(token, value) {
  if (value == token.getEvaluatedPropertyDefault("HP")) {
    token.resetProperty("HP");
  } else {
    token.setProperty("HP", value);
  }
}

• name - The name of the property to reset.

See getPropertyDefault() and evalMacro() for MTScript equivalent.

Release Notes

• Added Token.resetProperty, Token.getPropertyDefault and Token.getEvaluatedPropertyDefault so JavaScript macros can reset properties if they match their default value.

This change is