YAML configuration binding to list is inconsistent

[bcalmac]

Consider the following configuration including a list:

@Component
@ConfigurationProperties(prefix = "listConfiguration")
public class ListConfiguration {

    private final List<String> someList = new ArrayList<>();

    public List<String> getSomeList() {
        return someList;
    }
}

When the list is defined with 1 item per line, it all works as expected, getSomeList() returns [1, 2, 3]

listConfiguration:
    someList:
        - 1
        - 2
        - 3

However, when the list is defined on a single line, getSomeList() returns [].

listConfiguration:
    someList: 1, 2, 3

This can be fixed by giving up immutability and adding a setSomeList() setter, but I would say that the current behavior is error prone. You'd normally expect the two list definitions to be equivalent.

Maybe this is just something to keep in mind when implementing #8762.

Tested on 1.5.6-RELEASE.

[wilkinsona]

This has already been addressed in the binder improvements in 2.0