typescript/await-thenable Correctness

✅ This rule is turned on by default.

🚧 An auto-fix is still under development.

What it does

This rule disallows awaiting a value that is not a Thenable.

Why is this bad?

While it is valid JavaScript to await a non-Promise-like value (it will resolve immediately), this practice can be confusing for readers who are not aware of this behavior. It can also be a sign of a programmer error, such as forgetting to add parentheses to call a function that returns a Promise.

Examples

Examples of incorrect code for this rule:

await 12;
await (() => {});

// non-Promise values
await Math.random;
await { then() {} };

// this is not a Promise - it's a function that returns a Promise
declare const getPromise: () => Promise<string>;
await getPromise;

Examples of correct code for this rule:

await Promise.resolve("value");
await Promise.reject(new Error());

// Promise-like values
await {
  then(onfulfilled, onrejected) {
    onfulfilled("value");
  },
};

// this is a Promise - produced by calling a function
declare const getPromise: () => Promise<string>;
await getPromise();

How to use

To enable this rule in the CLI or using the config file, you can use:

CLI

oxlint --deny typescript/await-thenable

Config (.oxlintrc.json)

{
  "rules": {
    "typescript/await-thenable": "error"
  }
}

References

• Rule Source