Remove PHP7 language features and add PHP 5.6 compatible syntax :)
Install:
composer require janpiet/php-version-transpiler
Usage:
_Bin_Path/_php-version-transpiler _PHP_7_Source_Directory_ _PHP_5_6_Target_Directory_
Run tests:
composer install
bin/phpunit
View the files it generates:
- Input:
tests/_fixtures - Output:
tests/_out
requires composer & php7
composer install
bin/phpunit
As with every solution to such a problem there is no way to solve erverything, and there is no way to solve everything with one thing. I suspect there will far more use cases for a Shim for many incompatibility between 5.6 and 7.0. Other stuff will be that hard to detect, that I am not sure it will be worth it. Especially some of the more subtle additions to the language will not be emaulatable. But maybe they are not worth pursuing either?
| Feature | Supported | Emulated | Possible | SHIM | Notes |
|---|---|---|---|---|---|
| Scalar type declarations | x | - | x | - | |
| Return type declarations | x | - | x | - | |
| Null coalescing operator | x | x | x | - | |
| Spaceship operator | x | x | ? | - | |
| Constant arrays using define() | - | - | x | - | |
| Anonymous classes | x | x | x | - | But get_class() will now give something real back |
| Unicode codepoint escape syntax | - | - | partly? | partly? | Would need a shim |
| Closure::call() | - | - | x | - | |
| Filtered unserialize() | - | - | x | - | Generally a very hard implementation for such a simple feature |
| IntlChar | - | - | - | x | |
| Expectations | - | - | - | - | It is backwards compatible |
| Group use declarations | - | - | x | - | |
| Generator Return Expressions | - | - | partly? | partly? | Would need a shim |
| Generator delegation | - | - | - | - | |
| Integer division with intdiv() | - | - | - | x | Should be much easier to do this by Shim |
| Session options | - | - | ? | - | maybe, but might be leaky |
| preg_replace_callback_array() | - | - | x | - | Can be very easily a Shim |
| CSPRNG Functions | - | - | . | - | Can be very easily a Shim |
| Feature | Supported | Emulated | Possible | SHIM | Notes |
|---|---|---|---|---|---|
| Changes to error and exception handling | - | - | x | - | The docs contain a way out |
| Changes to the handling of indirect variables, properties, and methods | - | - | x | - | |
| Changes to list() handling | - | - | ? | - | |
| Array ordering when elements are automatically created during by reference assignments has changed | - | - | - | - | And never will be.... |
| Parentheses around function parameters no longer affect behaviour | - | - | x | - | Can be removed automatically |
| foreach no longer changes the internal array pointer | - | - | - | - | Therefore current() is essentially rendered useless here |
| foreach by-value operates on a copy of the array | - | - | partly? | partly? | Would need support from a shim, might be hard to detect |
| foreach by-reference has improved iteration behaviour | - | - | partly? | partly? | Would need support from a shim, might be hard to detect |