cypress: document.execCommand("copy") does not work in cypress

Hi there,

I’m curious as to why a document.execCommand("copy") fails when being run during a cypress test (as a side effect to a cy.get().click() ). Curiously it works fine once I’m manually clicking the same element after the test has run.

The failing test in question can be reproduced by running the following code:

describe("menuBar", function() {
  beforeEach(() => {
    cy.visit("http://teselagen.github.io/openVectorEditor/#/Editor");
  });
  
  it("select range, copy, cut works", function() {
    cy.clock()
    cy.get('.tg-menu-bar').contains("Edit").click()
    cy.get('.tg-menu-bar-popover').contains("Select").click()
    cy.get(`[label="From:"]`).clear().type("10")
    cy.get(`[label="To:"]`).clear().type("20")
    cy.get(`.dialog-buttons`).contains("OK").click()
    cy.get(".veStatusBar").contains(`10 to 20`)

    cy.get(".veStatusBar").contains(`5299`)
    cy.get('.tg-menu-bar').contains("Edit").click().tick(200)
    cy.get('.tg-menu-bar-popover').contains("Copy").click()
    cy.contains("Selection Copied")
    cy.get('.tg-menu-bar').contains("Edit").click()
    cy.get('.tg-menu-bar-popover').contains("Cut").click()
    cy.contains("Selection Cut")
    cy.get(".veStatusBar").contains(`5288`)
  });
});

If you run the above example, the test will fail to find “Selection Copied”. This is because

const worked = document.execCommand(type);

evaluates to false so the “Selection Copied” popover is not shown.

You can add a breakpoint manually to the commands/index.js file and see it not working.

Strangely, after the test has run if you manually click “File > Edit > Copy” then the document.execCommand("copy") works just fine. Not sure what is going on here to stop it from working when cypress is running its tests.

Thanks!