Testcase for undocumented PHP feature allowing to use default argument values in the middle of the argument list

DefaultArgs.php

<?php
/**
 * Declarations of necessary classes and functions
 */

class ClassA {}
class ClassB {}
class ClassC {}

function argsFirst (
    ClassA $arg1 = null,
    ClassB $arg2,
    ClassC $arg3
) {

  assert ( $arg1 instanceof ClassA || $arg1 === null );
  assert ( $arg2 instanceof ClassB );
  assert ( $arg3 instanceof ClassC );
}

function argsMiddle (
    ClassA $arg1,
    ClassB $arg2 = null,
    ClassC $arg3
) {

  assert ( $arg1 instanceof ClassA );
  assert ( $arg2 instanceof ClassB || $arg2 === null );
  assert ( $arg3 instanceof ClassC );
}

function argsLast (
    ClassA $arg1,
    ClassB $arg2,
    ClassC $arg3 = null
) {

  assert ( $arg1 instanceof ClassA );
  assert ( $arg2 instanceof ClassB );
  assert ( $arg3 instanceof ClassC || $arg3 === null );
}

function argsFirstAndLast (
    ClassA $arg1 = null,
    ClassB $arg2,
    ClassC $arg3 = null
) {

  assert ( $arg1 instanceof ClassA || $arg1 === null );
  assert ( $arg2 instanceof ClassB );
  assert ( $arg3 instanceof ClassC || $arg3 === null );
}

function argsAllButLast (
    ClassA $arg1 = null,
    ClassB $arg2 = null,
    ClassC $arg3
) {

  assert ( $arg1 instanceof ClassA || $arg1 === null );
  assert ( $arg2 instanceof ClassB || $arg2 === null );
  assert ( $arg3 instanceof ClassC );
}

function argsAll (
    ClassA $arg1 = null,
    ClassB $arg2 = null,
    ClassC $arg3 = null
) {

  assert ( $arg1 instanceof ClassA || $arg1 === null );
  assert ( $arg2 instanceof ClassB || $arg2 === null );
  assert ( $arg3 instanceof ClassC || $arg3 === null );
}

DefaultArgsTest.php

<?php
/**
 * Supported PHP versions:
 *    5.3.0
 *    5.3.1
 *    5.3.2
 *    5.3.3
 *    5.3.4
 *    5.3.5
 *    5.3.7
 *    5.3.8
 *    5.3.9
 *    5.3.10
 *    5.3.11
 *    5.3.12
 *    5.4.0
 *    5.4.1
 *    5.4.2
 *    5.4.3
 */

require_once dirname ( __FILE__ ) . '/DefaultArgs.php';


/**
 *
 */
class DefaultArgsTest extends PHPUnit_Framework_TestCase {

  private $_valA;
  private $_valB;
  private $_valC;

  public function setUp () {

    $this->_valA = new ClassA;
    $this->_valB = new ClassB;
    $this->_valC = new ClassC;
  }

  public function testCorrectCallsFirst () {

    argsFirst ( $this->_valA, $this->_valB, $this->_valC );
    argsFirst (         null, $this->_valB, $this->_valC );
  }

  public function testCorrectCallsMiddle () {

    argsMiddle ( $this->_valA, $this->_valB, $this->_valC );
    argsMiddle ( $this->_valA,         null, $this->_valC );
  }

  public function testCorrectCallsLast () {

    argsLast ( $this->_valA, $this->_valB, $this->_valC );

    argsLast ( $this->_valA, $this->_valB, null );
    argsLast ( $this->_valA, $this->_valB );
  }

  public function testCorrectCallsFirstAndLast () {

    argsFirstAndLast ( $this->_valA, $this->_valB, $this->_valC );

    argsFirstAndLast ( $this->_valA, $this->_valB, null );
    argsFirstAndLast ( $this->_valA, $this->_valB );

    argsFirstAndLast (         null, $this->_valB, null );
    argsFirstAndLast (         null, $this->_valB );
  }

  public function testCorrectCallsAllButLast () {

    argsAllButLast ( $this->_valA, $this->_valB, $this->_valC );

    argsAllButLast (         null, $this->_valB, $this->_valC );
    argsAllButLast ( $this->_valA,         null, $this->_valC );

    argsAllButLast (         null,         null, $this->_valC );
  }

  public function testCorrectCallsAll () {

    argsAll ( $this->_valA, $this->_valB, $this->_valC );

    argsAll (         null, $this->_valB, $this->_valC );
    argsAll ( $this->_valA,         null, $this->_valC );
    argsAll ( $this->_valA, $this->_valB,         null );
    argsAll ( $this->_valA, $this->_valB );

    argsAll (         null,         null, $this->_valC );
    argsAll (         null, $this->_valB,         null );
    argsAll (         null, $this->_valB );
    argsAll ( $this->_valA,         null,         null );
    argsAll ( $this->_valA,         null );
    argsAll ( $this->_valA );

    argsAll (         null,         null,         null );
    argsAll (         null,         null );
    argsAll (         null );
    argsAll ();
  }

  public function provideAllCalls () {

    return Array (
        Array ( "argsFirst" ),
        Array ( "argsMiddle" ),
        Array ( "argsLast" ),
        Array ( "argsFirstAndLast" ),
        Array ( "argsAllButLast" ),
        Array ( "argsAll" ),
    );
  }

  /**
   * @dataProvider provideAllCalls
   *
   * @expectedException PHPUnit_Framework_Error
   * @expectedExceptionMessage must be an instance of ClassA, integer given
   */
  public function testBadTypeFirst ( $call ) {

    $call ( 42, $this->_valB, $this->_valC );
  }

  /**
   * @dataProvider provideAllCalls
   *
   * @expectedException PHPUnit_Framework_Error
   * @expectedExceptionMessage must be an instance of ClassA, instance of ClassB given
   */
  public function testBadClassFirst ( $call ) {

    $call ( new ClassB, $this->_valB, $this->_valC );
  }

  /**
   * @dataProvider provideAllCalls
   *
   * @expectedException PHPUnit_Framework_Error
   * @expectedExceptionMessage must be an instance of ClassB, integer given
   */
  public function testBadTypeMiddle ( $call ) {

    $call ( $this->_valA, 42, $this->_valC );
  }

  /**
   * @dataProvider provideAllCalls
   *
   * @expectedException PHPUnit_Framework_Error
   * @expectedExceptionMessage must be an instance of ClassB, instance of ClassC given
   */
  public function testBadClassMiddle ( $call ) {

    $call ( $this->_valA, new ClassC, $this->_valC );
  }

  /**
   * @dataProvider provideAllCalls
   *
   * @expectedException PHPUnit_Framework_Error
   * @expectedExceptionMessage must be an instance of ClassC, integer given
   */
  public function testBadTypeLast ( $call ) {

    $call ( $this->_valA, $this->_valB, 42 );
  }

  /**
   * @dataProvider provideAllCalls
   *
   * @expectedException PHPUnit_Framework_Error
   * @expectedExceptionMessage must be an instance of ClassC, instance of ClassA given
   */
  public function testBadClassLast ( $call ) {

    $call ( $this->_valA, $this->_valB, new ClassA );
  }

  public function provideCallsThatRequireClassA () {

    return Array (
        Array ( "argsMiddle" ),
        Array ( "argsLast" ),
    );
  }

  /**
   * @dataProvider provideCallsThatRequireClassA
   *
   * @expectedException PHPUnit_Framework_Error
   * @expectedExceptionMessage must be an instance of ClassA, null given
   */
  public function testNullFirstType ( $call ) {

    $call ( null, $this->_valB, $this->_valC );
  }

  /**
   * @dataProvider provideCallsThatRequireClassA
   *
   * @expectedException PHPUnit_Framework_Error
   * @expectedExceptionMessage must be an instance of ClassA, none given
   */
  public function testNoneFirstType ( $call ) {

    $call ();
  }

  public function provideCallsThatRequireClassB () {

    return Array (
        Array ( "argsFirst" ),
        Array ( "argsLast" ),
        Array ( "argsFirstAndLast" ),
    );
  }

  /**
   * @dataProvider provideCallsThatRequireClassB
   *
   * @expectedException PHPUnit_Framework_Error
   * @expectedExceptionMessage must be an instance of ClassB, null given
   */
  public function testNullSecondType ( $call ) {

    $call ( $this->_valA, null, $this->_valC );
  }

  /**
   * @dataProvider provideCallsThatRequireClassB
   *
   * @expectedException PHPUnit_Framework_Error
   * @expectedExceptionMessage must be an instance of ClassB, none given
   */
  public function testNoneSecondType ( $call ) {

    $call ( $this->_valA );
  }

  public function provideCallsThatRequireClassC () {

    return Array (
        Array ( "argsFirst" ),
        Array ( "argsMiddle" ),
        Array ( "argsAllButLast" ),
    );
  }

  /**
   * @dataProvider provideCallsThatRequireClassC
   *
   * @expectedException PHPUnit_Framework_Error
   * @expectedExceptionMessage must be an instance of ClassC, null given
   */
  public function testNullLastType ( $call ) {

    $call ( $this->_valA, $this->_valB, null );
  }

  /**
   * @dataProvider provideCallsThatRequireClassC
   *
   * @expectedException PHPUnit_Framework_Error
   * @expectedExceptionMessage must be an instance of ClassC, none given
   */
  public function testNoneLastType ( $call ) {

    $call ( $this->_valA, $this->_valB );
  }
}

NoPHPUnit.php

<?php
/**
 * Simple test script to execute without PHPUnit
 */

require_once dirname ( __FILE__ ) . '/DefaultArgs.php';

$valA = new ClassA;
$valB = new ClassB;
$valC = new ClassC;

argsFirst ( $valA, $valB, $valC );
argsMiddle ( $valA, $valB, $valC );
argsLast ( $valA, $valB, $valC );
argsFirstAndLast ( $valA, $valB, $valC );
argsAllButLast ( $valA, $valB, $valC );
argsAll ( $valA, $valB, $valC );

argsFirst ( null, $valB, $valC );
argsMiddle ( $valA, null, $valC );
argsLast ( $valA, $valB, null );
argsFirstAndLast ( null, $valB, null );
argsAllButLast ( null, null, $valC );
argsAll ( null, null, null );

argsLast ( $valA, $valB );
argsFirstAndLast ( null, $valB );
argsAll ( null, null );
argsAll ( null );
argsAll ();