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jest/valid-expect Correctness

What it does

Checks that expect() is called correctly.

Why is this bad?

expect() is a function that is used to assert values in tests. It should be called with a single argument, which is the value to be tested. If you call expect() with no arguments, or with more than one argument, it will not work as expected.

Example

Examples of incorrect code for this rule:

javascript
expect();
expect("something");
expect(true).toBeDefined;
expect(Promise.resolve("Hi!")).resolves.toBe("Hi!");

Examples of correct code for this rule:

javascript
expect("something").toEqual("something");
expect(true).toBeDefined();
expect(Promise.resolve("Hi!")).resolves.toBe("Hi!");

This rule is compatible with eslint-plugin-vitest, to use it, add the following configuration to your .eslintrc.json:

json
{
  "rules": {
    "vitest/valid-expect": "error"
  }
}

References

Released under the MIT License.