jest/valid-expect-in-promise Correctness
What it does
Ensures that expect calls inside promise chains (.then(), .catch(), .finally()) are properly awaited or returned from the test.
Why is this bad?
When expect is called inside a promise callback that is not awaited or returned, the test may pass even if the assertion fails because the test completes before the promise resolves. This leads to silently passing tests with broken assertions.
Examples
Examples of incorrect code for this rule:
javascript
test("promise test", async () => {
something().then((value) => {
expect(value).toBe("red");
});
});
test("promises test", () => {
const onePromise = something().then((value) => {
expect(value).toBe("red");
});
const twoPromise = something().then((value) => {
expect(value).toBe("blue");
});
return Promise.any([onePromise, twoPromise]);
});Examples of correct code for this rule:
javascript
test("promise test", async () => {
await something().then((value) => {
expect(value).toBe("red");
});
});
test("promises test", () => {
const onePromise = something().then((value) => {
expect(value).toBe("red");
});
const twoPromise = something().then((value) => {
expect(value).toBe("blue");
});
return Promise.all([onePromise, twoPromise]);
});How to use
To enable this rule using the config file or in the CLI, you can use:
json
{
"plugins": ["jest"],
"rules": {
"jest/valid-expect-in-promise": "error"
}
}ts
import { defineConfig } from "oxlint";
export default defineConfig({
plugins: ["jest"],
rules: {
"jest/valid-expect-in-promise": "error",
},
});bash
oxlint --deny jest/valid-expect-in-promise --jest-pluginVersion
This rule was added in v1.60.0.