Shows how to control dependencies during tests using cy.spy and cy.stub

Shows how to load application code directly from the spec code and shows how to:

• use cy.spy() to assert that expected calls were made
• use cy.stub() to replace actual methods calls with synthetic responses
• Handle promises returned by stubbed functions.
• Handle callbacks in stubbed functions.

• "Stubs, spies and clocks"
• cy.spy
• cy.stub