cypress-expect

Cypress CLI wrapper where you can specify the total number of expected tests. Read Wrap Cypress Using NPM Module API and Cypress Metaprogramming

Use

Assuming cypress has been installed already

npm i -D cypress-expect # or yarn add -D cypress-expect
# instead of "cypress run ..."
npx cypress-expect run --passing <N> ...

Where N is the number of total tests expected to pass.

The rest of the arguments is parsed using Cypress CLI method and executed via cypress.run. Thus the execution should match the regular cypress run ... command.

Note: when running in parallel mode where the tests are split, this module would not work, since only a subset of specs will execute on the current machine.

Tip: Cypress has 4 test statuses explained in the Writing and Organizing Tests guide.

Options

--passing <N> checks if the total number of passing tests is <N>

--min-passing <N> checks if the total number of passing tests is >= <N>

--failing <N> checks if the total number of failing tests is <N>

--pending <N> checks if the total number of pending tests is <N>

--expect <path/to/file.json> checks test status against test names in a JSON file, see the details below

--expect-exactly <path/to/file.json> checks test status against test names in a JSON file, see the details below

expected test results

The --expect option is interesting as it allows you to specify the expected test statuses in a JSON file. Each object key is a suite name, and individual string keys and values are the test names and statuses. For example, the following spec file cypress/failing/spec.js has a suite with 2 tests, first should pass, and the second is expected to fail:

describe('1 passing 1 failing', () => {
  it('passes', () => { ... })

  it('fails', () => {
    expect(true).to.be.false
  })
})

You can list the expected test results in a JSON file, for example see cypress/failing/expected.json. The file should show the structure of the spec:

{
  "cypress": {
    "failing": {
      "spec.js": {
        "1 passing 1 failing": {
          "passes": "passed",
          "fails": "fail"
        }
      }
    }
  }
}

You can if the tests really behave this way by running:

$ npx cypress-expect run --expect ./cypress/failing/expected.json

Tip: you do not have to list the passing tests. Every test not listed in the expected JSON is assumed "passing" by default.

Tip 2: you do not have to remember the precise name of each test status, the JSON file can use synonyms, like passed, pass, passing, pass.

Tip 3: if there are more tests listed in the expected JSON file, the process will error with the list of tests not found

cypress-expect: expected the find the following tests
* login tests / first test
* authentication test

exactly expected test results

When using --expect <filename> option, the test run might have extra passing test results. When using --expect-exactly <filename> option, the test run cannot have any additional test results. All tests results must match exactly what is listed in the file.

Empty specs

Sometimes a spec is empty, or all tests were filtered out. In this case, the exact expected result should have an empty object, see the "empty-specs" tests

{
  "cypress": {
    "empty-specs": {
      "empty.js": {}
    }
  }
}

If the expected empty object is missing, then the empty spec should not run.

Debugging

Run this script with environment variable DEBUG=cypress-expect to see verbose logs

Small print

Author: Gleb Bahmutov <gleb.bahmutov@gmail.com> © 2021

• @bahmutov
• glebbahmutov.com
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• presentations
• cypress.tips

License: MIT - do anything with the code, but don't blame me if it does not work.

Support: if you find any problems with this module, email / tweet / open issue on Github

MIT License

Copyright (c) 2021 Gleb Bahmutov <gleb.bahmutov@gmail.com>

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.