Transfer component's filterOption prop doesn't work unless something is entered in the search box

[ivan-tkatchev]

Reproduction link

https://codesandbox.io/s/antd-reproduction-template-forked-p0hnr1

Steps to reproduce

When a Transfer component has a filterOption prop that doesn't depend on search filter state, it will not be triggered unless a non-empty string is entered into the search filter input.

What is expected?

filterOption should work regardless of whether something is entered into the search input.

What is actually happening?

User is forced to type something into the search input for filtering to occur.

Environment	Info
antd	5.1.1
React	17.0.1
System	Linux
Browser	Mozilla

[afc163]

Like Select/AutoComplete, Transfer filterOption prop works in searching situation. If you need to filter items in initial situation, please filter dataSource before passed to Transfer.

#39916

[ivan-tkatchev]

I need to filter the left (available items) pane only. If I filter the dataSource before passing to Transfer this affects the items in the right (selected items) pane too.

The use case is when additional widgets are doing searching/filtering of the available items list. (E.g. a select input with preset filtering options.)