1. Mirror, Mirror on the Wall
James Titcumb
NomadPHP December 2015

2. James Titcumb
www.jamestitcumb.com
www.roave.com
www.phphants.co.uk
www.phpsouthcoast.co.uk
@asgrim
Who is this guy?

3. Reflection

5. © 1937 Disney’s Snow White - disneyscreencaps.com

7. ● Structure
● Metadata
● Values
● Type introspection
● Modification
Reflection

8. How does it work?

9. GET_REFLECTION_OBJECT_PTR(ce);
lc_name = zend_str_tolower_dup(name, name_len);
if ((ce == zend_ce_closure && (name_len == sizeof(ZEND_INVOKE_FUNC_NAME)-1)
&& memcmp(lc_name, ZEND_INVOKE_FUNC_NAME, sizeof(ZEND_INVOKE_FUNC_NAME)-1) == 0)
|| zend_hash_str_exists(&ce->function_table, lc_name, name_len)) {
efree(lc_name);
RETURN_TRUE;
} else {
efree(lc_name);
RETURN_FALSE;
}

10. Okay. What now?

11. github.com/ /BetterReflection
Better Reflection!

13. What?

14. Why?

15. How?

16. Magic of the AST

17. source: http://goo.gl/HORwLQ

18. WTF is AST?

19. use PhpParserParserFactory;
$parser = (new ParserFactory)
->create(ParserFactory::PREFER_PHP7);
print_r($parser->parse(
file_get_contents('ast-demo-src.php')
));

20. <?php
echo "Hello world";

21. AST
`-- Echo statement
`-- String, value "Hello world"

22. <?php
echo "Hello " . "world";

23. AST
`-- Echo statement
`-- Concat
|-- Left
| `-- String, value "Hello "
`-- Right
`-- String, value "world"

24. AST to Reflection

25. Benefits?

26. ReflectionProperty->getDocBlockTypes()
Types!

27. Using Better Reflection

28. $reflection = new ReflectionClass(
'BetterReflectionTestFixtureExampleClass'
);
$this->assertSame(
'ExampleClass',
$reflection->getShortName()
);

29. $reflection = ReflectionClass::createFromName(
'BetterReflectionTestFixtureExampleClass'
);
$this->assertSame(
'ExampleClass',
$reflection->getShortName()
);

30. // In ReflectionClass :
public static function createFromName($className)
{
return ClassReflector::buildDefaultReflector()->reflect($className);
}
// In ClassReflector :
public static function buildDefaultReflector()
{
return new self(new AggregateSourceLocator([
new PhpInternalSourceLocator(),
new EvaledCodeSourceLocator(),
new AutoloadSourceLocator(),
]));
}

31. (don’t try this at home kids!)
Some voodoo...

33. class MyClass
{
public function foo()
{
return 5;
}
}

34. // Create the reflection first
// ***BEFORE*** class is loaded
$classInfo = ReflectionClass::createFromName('MyClass');

35. // Override the body...!
$methodInfo = $classInfo->getMethod('foo');
$methodInfo->setBody(function () {
return 4;
});

36. // Save the class and require it
$classCode = (new CodePrinter())->prettyPrint([$classInfo->getAst()]);
$tmpFile = tempnam(sys_get_temp_dir(), 'br-monkey-patching');
file_put_contents($tmpFile, '<?php ' . $classCode);
require_once($tmpFile);
unlink($tmpFile);

37. // Now create an instance, and call the function...
$c = new MyClass();
var_dump($c->foo()); // will be 4!!!

39. What’s in it for me?

40. The future...

41. ● DONE Currently: rewriting the internals
○ SourceLocators “might” return some code ?!
● DONE Returning AST/Code for method/fn
Ideas/plans - DONE

42. ● WIP More compatibility core reflection
● WIP Reflect core fns with default params
○ This is not currently possible with core reflection
● WIP Modification & exporting
● WIP Reflecting on closures
Ideas/plans - WIP

43. ● Adding a getColumn() function
● PHP 7 compatibility
● @inheritDoc traversal (to inherit type hints)
● Make it faster
Ideas/plans

44. ¯_(ツ)_/¯

45. github.com/ /BetterReflection
Better Reflection

46. Any questions? :)
https://joind.in/16523
James Titcumb @asgrim