From f049f5bf0788f406baadba9d543555f720efdf07 Mon Sep 17 00:00:00 2001
From: David Grudl <david@grudl.com>
Date: Mon, 25 Nov 2024 11:38:08 +0100
Subject: [PATCH] creating lazy services in PHP 8.4 WIP

---
 src/DI/Definitions/ServiceDefinition.php  | 36 +++++++++++++++++------
 src/DI/Extensions/DIExtension.php         | 15 ++++++++++
 src/DI/Extensions/DefinitionSchema.php    |  1 +
 src/DI/Extensions/ServicesExtension.php   |  4 +++
 tests/DI/Compiler.loadConfig.include.phpt |  1 +
 5 files changed, 48 insertions(+), 9 deletions(-)

diff --git a/src/DI/Definitions/ServiceDefinition.php b/src/DI/Definitions/ServiceDefinition.php
index 0546b54b3..9b26b2871 100644
--- a/src/DI/Definitions/ServiceDefinition.php
+++ b/src/DI/Definitions/ServiceDefinition.php
@@ -11,6 +11,7 @@
 
 use Nette;
 use Nette\DI\ServiceCreationException;
+use Nette\Utils\Strings;
 
 
 /**
@@ -24,6 +25,8 @@ final class ServiceDefinition extends Definition
 {
 	use Nette\SmartObject;
 
+	public ?bool $lazy = null;
+
 	private Statement $creator;
 
 	/** @var Statement[] */
@@ -181,18 +184,33 @@ private function prependSelf(Statement $setup): Statement
 
 	public function generateCode(Nette\DI\PhpGenerator $generator): string
 	{
-		$code = $this->creator->generateCode($generator) . ";\n";
-		if (!$this->setup) {
-			return 'return ' . $code;
+		$lines = [];
+		foreach ([$this->creator, ...$this->setup] as $stmt) {
+			$lines[] = $stmt->generateCode($generator) . ";\n";
 		}
 
-		$code = '$service = ' . $code;
-		foreach ($this->setup as $setup) {
-			$code .= $setup->generateCode($generator) . ";\n";
+		$class = $this->creator->getEntity();
+		$lazy = PHP_VERSION_ID >= 80400
+			&& $this->lazy
+			&& is_string($class)
+			&& ($ancestor = ($tmp = class_parents($class)) ? array_pop($tmp) : $class)
+			&& !(new \ReflectionClass($ancestor))->isInternal()
+			&& !preg_grep('#(?:func_get_arg|func_num_args)#i', $lines); // latteFactory workaround
+
+		if ($lazy) {
+			$lines[0] = (new \ReflectionClass($class))->hasMethod('__construct')
+				? $generator->formatPhp("\$service->__construct(...?:);\n", [$this->creator->arguments])
+				: '';
+			return "return new ReflectionClass($class::class)->newLazyGhost(function (\$service) {\n"
+				. Strings::indent(implode('', $lines))
+				. '});';
+
+		} elseif (count($lines) === 1) {
+			return 'return ' . $lines[0];
+
+		} else {
+			return '$service = ' . implode('', $lines) . 'return $service;';
 		}
-
-		$code .= 'return $service;';
-		return $code;
 	}
 
 
diff --git a/src/DI/Extensions/DIExtension.php b/src/DI/Extensions/DIExtension.php
index 5b789cffa..ce17727d4 100644
--- a/src/DI/Extensions/DIExtension.php
+++ b/src/DI/Extensions/DIExtension.php
@@ -10,6 +10,7 @@
 namespace Nette\DI\Extensions;
 
 use Nette;
+use Nette\DI\Definitions\ServiceDefinition;
 use Tracy;
 
 
@@ -36,6 +37,7 @@ public function __construct(bool $debugMode = false)
 			public array $excluded = [];
 			public ?string $parentClass = null;
 			public object $export;
+			public bool $lazy = false;
 		};
 		$this->config->export = new class {
 			public bool $parameters = true;
@@ -56,6 +58,19 @@ public function loadConfiguration(): void
 	}
 
 
+	public function beforeCompile(): void
+	{
+		if ($this->config->lazy) {
+			$builder = $this->getContainerBuilder();
+			foreach ($builder->getDefinitions() as $def) {
+				if ($def instanceof ServiceDefinition) {
+					$def->lazy ??= true;
+				}
+			}
+		}
+	}
+
+
 	public function afterCompile(Nette\PhpGenerator\ClassType $class): void
 	{
 		if ($this->config->parentClass) {
diff --git a/src/DI/Extensions/DefinitionSchema.php b/src/DI/Extensions/DefinitionSchema.php
index a49ab3faa..487ddecae 100644
--- a/src/DI/Extensions/DefinitionSchema.php
+++ b/src/DI/Extensions/DefinitionSchema.php
@@ -173,6 +173,7 @@ private static function getServiceSchema(): Schema
 			'tags' => Expect::array(),
 			'reset' => Expect::array(),
 			'alteration' => Expect::bool(),
+			'lazy' => Expect::bool(),
 		]);
 	}
 
diff --git a/src/DI/Extensions/ServicesExtension.php b/src/DI/Extensions/ServicesExtension.php
index 8bb50257d..075cf54a3 100644
--- a/src/DI/Extensions/ServicesExtension.php
+++ b/src/DI/Extensions/ServicesExtension.php
@@ -113,6 +113,10 @@ private function updateServiceDefinition(Definitions\ServiceDefinition $definiti
 		if (isset($config->inject)) {
 			$definition->addTag(InjectExtension::TagInject, $config->inject);
 		}
+
+		if (isset($config->lazy)) {
+			$definition->lazy = $config->lazy;
+		}
 	}
 
 
diff --git a/tests/DI/Compiler.loadConfig.include.phpt b/tests/DI/Compiler.loadConfig.include.phpt
index 26d00f815..590afe064 100644
--- a/tests/DI/Compiler.loadConfig.include.phpt
+++ b/tests/DI/Compiler.loadConfig.include.phpt
@@ -49,6 +49,7 @@ Assert::equal([
 			'tags' => [],
 			'reset' => [],
 			'alteration' => null,
+			'lazy' => null,
 			'defType' => Nette\DI\Definitions\ServiceDefinition::class,
 		],
 	],