SimpleTest conversion

Overview

The migration is pretty straightforward:

1. create new test file in `xxx/tests/yyy_test.php`
2. copy contents of the old test file
3. replace extends UnitTestCase with extends basic_testcase and extends UnitTestCaseUsingDatabase with extends advanced_testcase
4. move constructor code to setUp
5. fix setUp(), tearDown()
6. fix assert syntax
7. add $this->resetAfterTest() in advanced test cases that modify database
8. add missing global $CFG for includes outside of testcase classes

Assert differences

SimpleTest	PHPUnit	Notes
$this->assertEqual($expected, $actual)	$this->assertEquals($expected, $actual)
$this->assertIdentical($expected, $actual)	$this->assertSame($expected, $actual)
$this->assertTrue($actual)	$this->assertTrue((bool)$a, $b)	SimpleTest convers parameter to bool.
$this->assertFalse($actual)	$this->assertFalse((bool)$a, $b)	SimpleTest convers parameter to bool.
$this->expectException(true)	$this->setExpectedException('exception_name')
$this->expectError()	$this->setExpectedException('PHPUnit_Framework_Error')