Statical analysis for Latte [WIP]

[dg]

The purpose of this PR is to enable statical analysis of resulting code by analysers like PHPStan, Psalm, etc.

Related #262, #275, #276

First commit propagates known types infomation from {var type}, {varType}, {define}, {templateType} and {parameters} into compiled PHP code in form of /** @var type $var */ annotations.

The second commit propagates filter parameter in the form of @property annotations and stub class:

/**
* @property FiltersTemplate4d1f38ae82 $filters
*/
final class Template4d1f38ae82 extends Latte\Runtime\Template
{

	public function main(array $ʟ_args): void
	{
		echo LR\Filters::escapeHtmlText(($this->filters->lower)(($this->filters->upper)($a))) /* line 1 */;
	}
}

/**
* @property callable(mixed): string $lower
* @property callable(mixed): string $upper
*/
class FiltersTemplate4d1f38ae82
{
}

[JanTvrdik]

Very much looking forward to this. I did some initial testing and the main issue I encountered is, that it does not support "closure" variables, i.e. $foo would be reported as undefined in the template bellow.

{define outer, Foo $foo}
	{embed wrapper}
		{block inner}{$foo->text}{/block}
	{/embed}
{/define}

[MartinMystikJonas]

@dg: I tried fist attempts to migrate my tests to your implementation. SO far I notived few things I would need to solve before I continue:

1. There are many failing tests currently some of them are tests I want to extend by additional checks. It would be best if you could fix these tests befaore I start adding new checks.
2. When you print variable type comments for multiple variable it is printen on single line like this /** @var string $a *//** @var string $c */ I think it would be best to print each var on separate line for better readability and also it would simplify some tests expects.
3. When I prepared my implementation I stumbled upon one problem. Tag {varType} does not diffrentiate between specifying global varibles (passed to template) and local variables (created inside template). This becomes problem when you starts to use blocks. Because block see only global variables and not local variables (unless explicitly passed). Your implementation adds all types from {varType} to global scope so it is printet also inside block where these variables are not available. I solved this issue by adding variables to global scope only if {varType} is used in template head and othervise it will just output type comment in place. This is snippet of my code:

$comment = "/** @var $type $variable */\n";
		if ($this->getCompiler()->isInHead()) {
			$this->getCompiler()->paramsExtraction .= $comment;
			return "";
		} else {
			return $writer->write($comment);
		}

[MartinMystikJonas]

@dg Example of global/local sope test I wrote in my implementation:

$template = <<<'XX'

{varType string $a}

{$a}

{varType string $c}
{var $c = 10}

{include test}

{define test}
  {varType int $b}
  {var $b = 5}
  {$a}{$b}
{/define}

XX;

Assert::matchFile(
	__DIR__ . '/expected/varType.phtml',
	$latte->compile($template)
);

Expects vartype.phtml:

<?php
%A%
	public function main(): array
	{
		extract($this->params);
		/** @var string $a */
%A%
	public function blockTest(array $ʟ_args): void
	{
		extract($this->params);
		/** @var string $a */
%A%
		/** @var int $b */
		$b = 5%a%;
%A%

Notice that in blockTest there is no variable type comment for $c, which is local variable.

[MartinMystikJonas]

@dg: Here you can find my first patch https://gist.github.com/MartinMystikJonas/05a11cbbb404184493b2353f4041a6bc

It includes:

1. Fix for most tests
2. When there is multiple variable comments each comment is printed on separate line
3. Backward compatible whitespaces when variable types are not used (prevents need to update may test expects)
4. Fixed buf with {default} - it called addExpression but with string parameter not expression
5. Draft of new test for {varType}