README.md

ExitDieException

Provides a way to unit-test code that makes extensive use of exits and dies. Early returns can also be caught and tested for.

Usage:

index_wrapper.php:

<?php
require_once 'exit_die_exception.php';

try {
  require 'index.php';
}
catch (ExitDieException $e) {
  exit $e->getMessage;  // string
  // or
  exit $e->getCode; // integer
}

Now in index.php or any files included/required by it, you can replace:

• die 'message'; with throw new DieException('message');
• die 42; with throw new DieException('', 42);
• exit 'message'; with throw new ExitException('message');
• exit 42; with throw new ExitException('', 42);

This allows you to test for early exits/dies in your unit-tests, without killing the entire test. Simply use similar code to the above inside the test instead of calling the wrapper file. e.g. in Codeception:

  // tests
  public function testShouldThrowAnExitException() {
    $this->tester->expectException(new ExitDieException, function() {
      throw new ExitException;
    });
  }

Eventually, you will want to refactor your code to get rid of both all the exits/dies and the ExitDieExceptions. This allows you to unit test your code as you work towards this goal.

In a similar vein, the ReturnException allows you to replace troublesome early returns within functions and methods as you're refactoring. As an example, you decide to perform Extract Method on some code within a method. But, uh oh! the code you've just extracted contained an early return! So, previously, you were returning from the parent method, but now you're returning from the child method and executing the remainer of the parent's code! You've unintentionally changed the behaviour!

This is where ReturnException comes in.

  function parent() {
    try {
      $this->child();
    }
    catch (ReturnException $e) {
      return $e->value();
    }

    // Remainder of original parent code
    // ...
  }

  function child() {
    // Part of code previously in parent()
    // ...
    throw (new ReturnException)->response($return_value);
  }

Again, this is intended to be a temporary measure to allow you to refactor your code and eventually eliminate the need for ReturnException. One of the good things about both of these methods is that you can search through your project for remaining instances of ExitException, DieException and ReturnException to know what still needs cleaning up.