As discussed on PR #121, if a promise is resolved with a null or undefined value, the fullfilled action will not include a payload property. This is because actions describe changes in state. Consider the following two actions:
// A
{
type: 'ACTION`,
meta: ...
}
// B
{
type: 'ACTION'
payload: null,
meta: ...
}
Objectively, one could argue both actions describe the same change in state. This is why, when you resolve with null or undefined, the payload property is not included. It would be redundant to include it.
If you believe this is illogical and would like to discuss further, please open a feature request issue.