# Writing IO tests

Another way we can write tests with Counsel is using Input/Output (IO) tests. The example will show basic conventions and steps for writing IO tests with Counsel:

IO tests are written in yaml files.
IO test file names need to end with *Test.yaml.
The most basic IO test will require the following fields:

test - a short description about what you want to test
perform - the input, command to run
expect - what should be the output

Optional fields for an IO test:

cwd - specify the current working directory the test
platform - specify one or more platforms within this test should run
skip - mark the IO test as skipped
assertions - specify basic true/false expectations

# Example

Example 2.1 - Testing the famous ls command with Counsel.

test: |
  "ls" command test
cwd: tests/doubles/ls-dir
perform: |
  ls
expect: |
  bar.txt
  baz.txt
  foo.txt
  sub-1
assertions:
  status: 0

# Real-world Counsel IO test example

test:
  Dot reporter error true and false output
perform:
  src/counsel.js --config dot-reporter-true-false-reporting-test.js --is-io-test
expect: |
  Counsel {{version}}

  xx                        2 / 2 (100%)

  x 1) CoreAssertionsTest -> it_is_able_to_assert_true
  {{root}}io-tests/dot-reporter-true-false-test/CoreAssertionsTest.js:6

  5|     {
  6|         this.assertTrue(false);
  7|     }

  Value is not truthy:

  false

  x 2) CoreAssertionsTest -> it_is_able_to_assert_false
  {{root}}io-tests/dot-reporter-true-false-test/CoreAssertionsTest.js:12

  11|     {
  12|         this.assertFalse(true);
  13|     }

  Value is not falsy:

  true

  Time: {{executionTimeFormatted}}

  2 failed, 2 tests
assertions:
  status: 2
  assertionsCount: 2
  assertionsFailuresCount: 2
  assertionsPassesCount: 0
  testsCount: 2
  testsFailuresCount: 2
  testsPassesCount: 0
  progress: 100

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