Rule: no-floating-promises

Promises returned by functions must be handled appropriately.

Unhandled Promises can cause unexpected behavior, such as resolving at unexpected times.


Creating a Promise and not storing or returning it may let other code run independently of its result. This can cause unexpected and/or non-deterministic behavior depending on external timing factors.

It’s typically better to return Promises from functions that start them, then handle them in calling code.

Use no-unused-expression in addition to this rule to reveal even more floating promises.



A list of ‘string’ names of any additional classes that should also be handled as Promises.

Config examples
"no-floating-promises": true
"no-floating-promises": [true, "JQueryPromise"]
  "type": "list",
  "listType": {
    "type": "array",
    "items": {
      "type": "string"