no-expect-for-stub.md

Avoid expect(stub)… (no-expect-for-stub)

Disallow usage of expect() with a Sinon-Chai chainer (e.g., expect(stub).to.have.been.calledOnce) preferring the usage of should().

Some problems reported by this rule are automatically fixable by the --fix command line option. Please be aware that fixing the code with this rule requires that the stub is aliased (using the .as() Cypress command): if that's not the case, you will have to add an alias manually for the test to pass.

Rule Details

This rule makes code easier to read when expect() is used on a stub with Sinon-Chai chainer chainer.

Example of incorrect code for this rule:

let onBudgetChanged = cy.stub().as("onBudgetChanged");
// … do something with onBudgetChanged…

cy.get("foo").click();

cy.then(() => {
	expect(onBudgetChanged).to.be.called;
});

Note that the expect() call is wrapped in a cy.then(). This is mandatory if the expect() is to be called after the Cypress commands above it which is usually the case.

Example of correct code for this rule:

// do something with cy.stub().as("onBudgetChanged")
cy.get("foo").click();
cy.get("@onBudgetChanged").should("be.called");

When Not To Use It

• When you don't mind having code that is harder to read than necessary.
• When you don't want to add aliases to the stubs/spies.