Runkit7: Unofficial runkit extension fork for PHP 7.0+

For all those things you.... probably shouldn't have been doing anyway.... but surely do! Now with partial support for PHP7.0, 7.1, 7.2, and 7.3! (function/method manipulation is recommended only for unit testing. Note that PHP 7.3 has known crashes in runkit_import() but other functionality works.)

Building and installing runkit in unix

Building and installing runkit in Windows

Compatibility: PHP7.0 to PHP 7.3

See runkit-api.php for the implemented functionality and method signatures. New functionality was added to support usage with PHP7.

This adds the ability to set return types (including nullable return types, in PHP 7.1) on added/redefined functions.
This adds the ability to set declare(strict_types=1) on added/redefined functions.

Superglobals work reliably when tested on web servers and tests. Class and function manipulation is recommended only for unit tests.

The runkit.superglobal ini setting works reliably in PHP 7.
Manipulating user-defined (i.e. not builtin or part of extensions) functions and methods via runkit_method_* and runkit_function_* generally works, but is recommended only in unit tests (unlikely to crash, but will cause memory leaks)
Manipulating built in functions may cause segmentation faults in rare cases. File a bug report if you see this. Function and method manipulation is recommended only for debugging or unit tests, because of the possibility of crashes. (Manipulating built in class methods is impossible/not supported)
Adding default properties to classes doesn't work in php7, because of a change in the way PHP stores objects. Eventually, I plan to add runkit_default_property_modify, which will replace one default value with a different default property, keeping the number of properties the same. See the reasons for disabling property manipulation at PROPERTY_MANIPULATION.md As a substitute, user code can do the following things:
- rename (or add) __construct with runkit_method_rename/runkit_method_add, and create a new version of __construct that sets the properties, then calls the original constructor.
- For getting/setting properties of individual objects, see ReflectionProperty ReflectionProperty->setAccessible(true) and ReflectionProperty->setValue(), etc.
Modifying constants works for constants declared in different files, but does not work for constants within the same file. PHP7.0+ inlines constants within the same file if they are guaranteed to have only one definition. Patching php-src and/or opcache to not inline constants (e.g. based on a php.ini setting) is possible, but hasn't been tried yet.
Sandboxing (and runkit_lint) were removed.
runkit_object_id works. If that function is the only function you need from runkit, see runkit7/runkit_object_id.

The following contributions are welcome:

Pull requests with PHP5 -> PHP7 code migration of functions
New test cases for features that no longer work in PHP7, or bug reports containing code crashing runkit7.
Issues for PHP language features that worked in PHP5, but no longer work in PHP7, for the implemented methods (runkit_function_* and runkit_method_*)
Fixes and documentation.

Most of the runkit tests for method manipulation and function manipulation are passing. Other methods and corresponding tests are disabled/skipped because changes to php internals in php7 made them impractical.

Examples

The following mocking libraries work with the runkit7 fork

timecop-PHP (Fork), a time testing library inspired by the ruby timecop gem (requires runkit.internal_override=1, suggested only for unit tests)
staticmock, a mockery-like DSL to replace static methods in tests.
SimpleStaticMock (Fork), a very simple class to mock static methods in unit tests. Unrelated to tototoshi/staticmock.
TraceOn (Fork), a simple PHP utility to trace(investigate) invocations of instance/static/global methods.

PHP7 SPECIFIC DETAILS

Bugs in PHP7 runkit

There are segumentation faults in runkit_import() in PHP 7.3 (confirmed on NTS)
There are segmentation faults when manipulating internal functions (a.k.a. "runkit.internal_override=1") (when you rename/redefine/(copy?) internal functions, and call internal functions with user functions' implementation, or vice versa) (and when functions redefinitions aren't cleaned up) Many (but not all) of these crashes have been fixed.
There are reference counting bugs causing memory leaks. 2 calls to emalloc have been temporarily replaced with calls to pemalloc so that tests would not crash during shutdown (and other reasons)
The Zend VM bytecode representation may change in 7.3 betas and in future minor/major PHP releases after 7.3. Any new opcodes added may not work as expected with each new minor php version release.

APIs for PHP7

Implemented APIs for PHP7

runkit_function_*: Most tests are passing. There are some memory leaks when renaming internal functions.
runkit_method_*: Most tests are passing. There are some memory leaks when renaming internal functions.
runkit_zval_inspect: Partly passing, and needs to be rewritten because of PHP7's zval changes.
runkit_constant_add works. Other constant manipulation functions don't work for constants accessed within the same file due to the compiler inlining their values for performance.
Runkit superglobals.
runkit_import Some flags are missing for PHP 7.x, especially properties, and other tests have known failures. See runkit7#73

Unsupported APIs for PHP7:

(These functions will be missing. Some of these should be possible to implement.)

runkit_class_adopt and runkit_class_emancipate Disabled because of bugs related to properties.
runkit_lint* Might be possible if this is rewritten to use actual threading: See issue #114
runkit_constant_* : runkit_constant_add works reliably, other methods don't. This works better when the constants are declared in a file separate from the file accessing that constant.
runkit_default_property_* Disabled because of bugs related to properties See issue #30 (implement function to modify only) and issue #113 (Manipulate static properties)

runkit_default_property_add has been removed in php7 - it requires reallocing a different zval to add a property to the property table That would break a lot of things (PHP internals, other PHP modules, etc)
runkit_return_value_used: Removed, was not working and unrelated to other features. vld seems to have a working implementation in the opcode analyzer, not familiar with how it works.

Reasons for disabling property manipulation

See PROPERTY_MANIPULATION.md

FURTHER WORK

See https://github.com/runkit7/runkit7/issues

Tasks for the near future:

Replace property manipulation with runkit_default_property_modify (runkit7#30)

Contributing

See CONTRIBUTING.md for guidelines on issues and pull requests, as well as links to resources that are useful for php7 module and runkit7 development.

UPSTREAM DOCUMENTATION

(runkit7 is an unofficial fork of https://github.com/zenovich/runkit, adding php7 support)

Features

Runkit has two groups of features outlined below (Sandboxing was removed in runkit7):

CUSTOM SUPERGLOBALS

A new .ini entry runkit.superglobal is defined which may be specified as a simple variable, or list of simple variables to be registered as superglobals. runkit.superglobal is defined as PHP_INI_SYSTEM and must be set in the system-wide php.ini.

Example:

php.ini:

runkit.superglobal=foo,bar

test.php:

function testme() {
  echo "Foo is $foo\n";
  echo "Bar is $bar\n";
  echo "Baz is $baz\n";
}
$foo = 1;
$bar = 2;
$baz = 3;

testme();

Outputs:

Foo is 1
Bar is 2
Baz is

USER DEFINED FUNCTION AND CLASS MANIPULATION

__NOTE: Only a subset of the APIs have been ported to PHP7. Some of these APIs have segmentation faults in corner cases __ (when runkit.internal_override=On)

User defined functions and user defined methods may now be renamed, delete, and redefined using the API described at http://www.php.net/runkit

Examples for these functions may also be found in the tests folder.

`runkit_lint` alternatives

runkit_lint was disabled with the rest of the sandbox code due to issues porting it to PHP 7 (Issue #114). As a replacement for runkit_lint/runkit_lint_file try any of the following:

php -l --no-php-ini $filename will quickly check if a file is syntactically valid, but will not show you any php notices about deprecated code, etc.
opcache_compile_file may help, but will not show you any notices.
token_get_all($code, TOKEN_PARSE) will detect invalid ASTs in php 7.0+
Projects such as PHP-Parser (Pure PHP) and php-ast (C module), which produce an Abstract Syntax Tree from php code. Alternately, token_get_all() will throw an error for syntax errors if the flag TOKEN_PARSE is passed in. (Unfortunately, it parses but does not detect erroneous code, e.g. duplicate classes/methods in the same file).
```
// Example replacement for runkit_lint.
try {
    $ast = token_get_all('<?php function foo(){}', TOKEN_PARSE)
    return true;
} catch (ParseError $e) {
    return false;
}
```
Alternately, you may wish to use a different approach and run a PHP static analyzer such as Phan, Psalm, or PHPStan

Installation

BUILDING AND INSTALLING RUNKIT(7) IN UNIX

git clone https://github.com/runkit7/runkit7.git
cd runkit7
phpize
# The sandbox related code and flags have been removed, no need to disable them.
# (--enable-runkit-modify (on by default) controls function, method, class, manipulation, and will control property manipulation)
# (--enable-runkit-super (on by default) allows you to add custom superglobals)
./configure
make
make test
sudo make install

Pecl tars are also included with newer GitHub releases.

Go to https://github.com/runkit7/runkit7/releases
Download the tgz file from the link (e.g. runkit-1.0.6.tgz)
pecl install ./runkit-1.0.6.tgz

BUILDING AND INSTALLING RUNKIT7 IN WINDOWS

Setting up php build environment

Read https://wiki.php.net/internals/windows/stepbystepbuild first. This is just a special case of these instructions.

For PHP7, you need to install "Visual Studio 2015 Community Edition" (or other 2015 edition). Make sure that C++ is installed with Visual Studio. The command prompt to use is "VS2015 x86 Native Tools Command Prompt" on 32-bit, "VS2015 x64 Native Tools Command Prompt" on 64-bit.

Note that different visual studio versions are needed for different PHP versions. For PHP 7.2+, use Visual Studio 2017 and vc15 instead.

For 64-bit installations of php7, use "x64" instead of "x86" for the below commands/folders.

After completing setup steps mentioned, including for C:\php-sdk\phpdev\vc14

extract download of php-7.0.30-src (or any version of php 7) to C:\php-sdk\phpdev\vc14\x86\php-7.0.30-src

Installing runkit7 on windows

There are currently no sources providing DLLs of this fork. Runkit7 and other extensions used must be built from source.

Create subdirectory C:\php-sdk\phpdev\vc14\x86\pecl, adjacent to php source directory)

extract download of runkit7 to C:\php-sdk\phpdev\vc14\x86\pecl\runkit7 (all of the c files and h files should be within runkit7, pecl is

Then, execute the following (Add --enable-runkit to the configure flags you were already using)

cd C:\php-sdk
C:\php-sdk\bin\phpsdk_setvars.bat
cd phpdev\vc14\x86\php-7.0.30\src
buildconf
configure --enable-runkit
nmake

Then, optionally test it (Most of the tests should pass, be skipped, or be known failures.):

nmake test TESTS="C:\php-sdk\vc14\x86\pecl\runkit7\tests

doit76/runkit7