I am trying to set some variables based on the results of a cy.exec() command for use later in the script. For example:
cy.exec('some command').then((result) => { let json = JSON.parse(result.stdout) this.foo = json.foo }) How can I wait for this.foo to be defined before proceeding with the rest of the script? I tried:
cy.exec('some command').as('results') cy.wait('@results') However this.results is undefined after the cy.wait() command.
You don't need aliases. Your code is correct, but you can't use this inside of a () => {}. You should use a function declaration to make use of this.
Try this instead:
cy.exec('some command').then(function(result) { let json = JSON.parse(result.stdout) this.foo = json.foo }) Note that Cypress is asynchronous. What this means is that if you do something like this:
cy.exec('some command').then(function(result) { let json = JSON.parse(result.stdout) this.foo = json.foo }) expect(this.foo).to.eq(expectedStdout) ...your test will always fail. this.foo = json.foo will be executed after the expect(this.foo)... is evaluated.
If you want to use this.foo in this way, just use the Promise returned by cy.exec():
cy.exec('some command').then(result => { return JSON.parse(result.stdout) }) .then(json => { // write the rest of your test here cy.get('blah').contains(json.something) }) 
before() and not trying to use this in an arrow function was the solution for me.