NodeDecorator

The node can be decorated in various ways. setImplementation decorates the node's lookup to return the same instance for each node.

graph.decorator.nodeDecorator.sizeConstraintProviderDecorator.setImplementation(
  new ConstantSizeConstraintProvider()
)

setImplementation with a predicate decorates the node's lookup only to return the same instance for each node for which the predicate returns true.

graph.decorator.nodeDecorator.sizeConstraintProviderDecorator.setImplementation(
  (node) => node.tag !== null,
  new ConstantSizeConstraintProvider()
)

setFactory calls the provided factory method to return a new instance of the queried type created for the given node or for nodes for which the predicate returns true, respectively:

graph.decorator.nodeDecorator.sizeConstraintProviderDecorator.setFactory(
  (node) => new CustomSizeConstraintProvider(node)
)
graph.decorator.nodeDecorator.sizeConstraintProviderDecorator.setFactory(
  (node) => node.tag !== null,
  (node) => new CustomSizeConstraintProvider(node)
)

setImplementationWrapper calls the provided factory method to return a new instance of the queried type which wraps the default implementation, once for all nodes and once only for nodes for which the predicate returns true.

graph.decorator.nodeDecorator.sizeConstraintProviderDecorator.setImplementationWrapper(
  (node, originalProvider) =>
    new SizeConstraintProviderWrapper(node, originalProvider)
)
graph.decorator.nodeDecorator.sizeConstraintProviderDecorator.setImplementationWrapper(
  (node) => node.tag !== null,
  (node, originalProvider) =>
    new SizeConstraintProviderWrapper(node, originalProvider)
)

Finally hideImplementation hides the default implementation by letting the lookup always return null for all nodes and for nodes for which the predicate returns true, respectively

graph.decorator.nodeDecorator.sizeConstraintProviderDecorator.hideImplementation()
graph.decorator.nodeDecorator.sizeConstraintProviderDecorator.hideImplementation(
  (node) => node.tag !== null
)

Each of these methods returns a IContextLookupChainLink which can be used to remove the modified behavior again:

/**
 * @param {!IGraph} graph
 */
registerLookup(graph) {
  this.chainLink =
    graph.decorator.nodeDecorator.sizeConstraintProviderDecorator.setFactory(
      (node) => new CustomSizeConstraintProvider(node)
    )
}

/**
 * @param {!IGraph} graph
 */
deregisterLookup(graph) {
  graph.decorator.nodeDecorator.remove(this.chainLink)
}registerLookup(graph: IGraph): void {
  this.chainLink =
    graph.decorator.nodeDecorator.sizeConstraintProviderDecorator.setFactory(
      (node) => new CustomSizeConstraintProvider(node)
    )!
}

deregisterLookup(graph: IGraph): void {
  graph.decorator.nodeDecorator.remove(this.chainLink)
}