Have you ever used PHP’s built in reflection, only to find you can’t do quite what you wanted? What about finding types for parameters or properties? What about reflecting on classes that aren’t loaded, so that you can modify them directly? Better Reflection is an awesome new library that uses magical time-warp techniques* (*actual magic or time-warp not guaranteed) to improve on PHP’s built-in reflection by providing additional functionality. In this talk we’ll briefly explore the cool features of Better Reflection, and how you can use Better Reflection in your projects to maximise your reflection-fu.

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