FLUID-6448: DataSource.get callback mentioned but not working

Description

The in-code documentation for fluid.dataSource mentions optional callback arguments in the get and set methods, but these don't seem to be able to work.

The documentation in question: https://github.com/fluid-project/infusion/blob/46a1b887dcc4d78a78b3c3f8faaab498afc782cd/src/framework/core/js/DataSource.js#L61-L79

The issue seems to be that the function fluid.dataSource.defaultiseOptions (the first thing called by both get and set) will error out (TypeError) if a function or string are passed in as the second argument. This would suggest that callback support is leftover from a previous factoring.

Further complicating matters, the last thing called by both get and set is fluid.dataSource.registerStandardPromiseHandlers which does include setting up a callback called on promise resolution.

Does it make sense to reinstate callback support, or would it be better to remove the comment and setup? It seems odd to return a promise and pass in a callback, but, in the absence of a task-like fixture outside of the IoC testing framework, I can imagine if it were being called in an invoker or listener that the callback arg would be useful.

Comments

• Justin Obara commented 2020-01-16T11:29:02.768-0500

  @@Antranig Basman do you have any thoughts on how to best address this?

• Gregor Moss commented 2020-01-16T11:30:10.663-0500

  The documentation that has been prepared by @@Justin Obara but hasn't yet been merged into the Infusion docs does not mention callbacks at all: https://github.com/fluid-project/infusion-docs/blob/82e47765367fc51b804794ac5e504b47cdd03966/src/documents/DataSourceAPI.md

• Antranig Basman commented 2020-01-21T07:58:48.951-0500

  I think it is best to cleanly axe callback support from impl and docs, this is rather old-fashioned and and unlikely to be of help to anybody.