Browser detection using user agent in fixture hook

I have a few tests that only need to be run when in a mobile browser. Currently I have a client function to check the user agent.

const checkMobile = ClientFunction(() => /iPhone|Android/i.test(navigator.userAgent))

Which I then access inside my tests:

test("Check if mobile", async t => { 
  const isMobile = await checkMobile();
  if (isMobile) {
    await t
    // do the tests
  }
}

Is there a way for me to use this in a fixture? Like a fixture which will only run if checkMobile is true? So I don't need to repeat this check in every test manually. I'm sure there's a smarter way to go about it than what I have right now. I tried doing the check in the fixture's beforeEach hook but it didn't work out for me to then try to share the outcome of that in a variable to pass down to the tests.

To share a variable from the fixture hook for testing, you can use fixture context http://devexpress.github.io/testcafe/documentation/test-api/test-code-structure.html#sharing-variables-between-fixture-hooks-and-test-code

In addition, you can reorganize your test in the following manner:

import { ClientFunction } from 'testcafe';


fixture `test`.page('http://example.com').beforeEach(async t => {
    const isMobile = await checkMobile();

    t.ctx.isMobile = isMobile;
})

const checkMobile = ClientFunction(() => /iPhone|Android/i.test(navigator.userAgent))

function testAndCheck (testName, testFn) {
    const foo = async t => {
        if (t.ctx.isMobile)
            await testFn(t)
        else
            throw new Error('not mobile');
    }

    test(testName, foo);
}

testAndCheck('test1', async t => {
    await t.click('h1');
    await t.click('div');
    await t.click('h1');
})

Here I define the testAndCheck function that extends the test function with an additional check for mobile devices.

In addition, you can refer to this comment https://github.com/DevExpress/testcafe/issues/1626#issuecomment-417424558 to see which other ways exist to overcome the issue.