Reuse parsed PHPDocs of equal strings

FileTypeMapper, InvalidPhpDocTagValueRule and InvalidPHPStanDocTagRule
parse the same PHPDoc strings, and the two rules parse each one directly
after the other. PhpDocStringResolver now keeps the most recently parsed
nodes in an LruCache, and the two rules use it instead of their own lexer
and parser. The new cache.parsedPhpDocCountMax parameter sets how many
nodes it keeps, 1024 by default.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

Author: SanderMuller

conf/config.neon

@@ -146,6 +146,7 @@ parameters:
 		phpStormStubsNodesCountMax: 128
 		memberCacheKeysMax: 2048
 		resolvedLocalTypeAliasesCountMax: 2048
+		parsedPhpDocCountMax: 1024
 	reportUnmatchedIgnoredErrors: true
 	reportIgnoresWithoutComments: false
 	typeAliases: []

conf/parametersSchema.neon

@@ -164,7 +164,8 @@ parametersSchema:
 		nameScopeMapMemoryCacheCountMax: int(),
 		phpStormStubsNodesCountMax: int(),
 		memberCacheKeysMax: int(),
-		resolvedLocalTypeAliasesCountMax: int()
+		resolvedLocalTypeAliasesCountMax: int(),
+		parsedPhpDocCountMax: int()
 	])
 	reportUnmatchedIgnoredErrors: bool()
 	reportIgnoresWithoutComments: bool()

src/PhpDoc/PhpDocStringResolver.php

@@ -2,7 +2,9 @@
 
 namespace PHPStan\PhpDoc;
 
+use PHPStan\DependencyInjection\AutowiredParameter;
 use PHPStan\DependencyInjection\AutowiredService;
+use PHPStan\Internal\LruCache;
 use PHPStan\PhpDocParser\Ast\PhpDoc\PhpDocNode;
 use PHPStan\PhpDocParser\Lexer\Lexer;
 use PHPStan\PhpDocParser\Parser\PhpDocParser;
@@ -12,16 +14,37 @@
 final class PhpDocStringResolver
 {
 
-	public function __construct(private Lexer $phpDocLexer, private PhpDocParser $phpDocParser)
+	/**
+	 * FileTypeMapper and the rules that validate PHPDocs parse the same strings, often one right after
+	 * another. The parsed nodes are not modified afterwards, so equal strings can share one node.
+	 *
+	 * @var LruCache<PhpDocNode>
+	 */
+	private LruCache $parsedPhpDocs;
+
+	public function __construct(
+		private Lexer $phpDocLexer,
+		private PhpDocParser $phpDocParser,
+		#[AutowiredParameter(ref: '%cache.parsedPhpDocCountMax%')]
+		int $parsedPhpDocCountMax,
+	)
 	{
+		$this->parsedPhpDocs = new LruCache($parsedPhpDocCountMax);
 	}
 
 	public function resolve(string $phpDocString): PhpDocNode
 	{
+		$phpDocNode = $this->parsedPhpDocs->get($phpDocString);
+		if ($phpDocNode !== null) {
+			return $phpDocNode;
+		}
+
 		$tokens = new TokenIterator($this->phpDocLexer->tokenize($phpDocString));
 		$phpDocNode = $this->phpDocParser->parse($tokens);
 		$tokens->consumeTokenType(Lexer::TOKEN_END); // @phpstan-ignore missingType.checkedException
 
+		$this->parsedPhpDocs->set($phpDocString, $phpDocNode, 0);
+
 		return $phpDocNode;
 	}
 

src/Rules/PhpDoc/InvalidPHPStanDocTagRule.php

@@ -8,9 +8,7 @@
 use PHPStan\DependencyInjection\RegisteredRule;
 use PHPStan\DependencyInjection\ValidatesStubFiles;
 use PHPStan\Node\VirtualNode;
-use PHPStan\PhpDocParser\Lexer\Lexer;
-use PHPStan\PhpDocParser\Parser\PhpDocParser;
-use PHPStan\PhpDocParser\Parser\TokenIterator;
+use PHPStan\PhpDoc\PhpDocStringResolver;
 use PHPStan\Rules\MultipleNodeTypesRule;
 use PHPStan\Rules\RuleErrorBuilder;
 use function in_array;
@@ -70,10 +68,7 @@ final class InvalidPHPStanDocTagRule implements MultipleNodeTypesRule
 		'@phpstan-all-methods-impure',
 	];
 
-	public function __construct(
-		private Lexer $phpDocLexer,
-		private PhpDocParser $phpDocParser,
-	)
+	public function __construct(private PhpDocStringResolver $phpDocStringResolver)
 	{
 	}
 
@@ -111,8 +106,7 @@ public function processNode(Node $node, Scope $scope): array
 			return [];
 		}
 		$phpDocString = $docComment->getText();
-		$tokens = new TokenIterator($this->phpDocLexer->tokenize($phpDocString));
-		$phpDocNode = $this->phpDocParser->parse($tokens);
+		$phpDocNode = $this->phpDocStringResolver->resolve($phpDocString);
 
 		$errors = [];
 		foreach ($phpDocNode->getTags() as $phpDocTag) {

src/Rules/PhpDoc/InvalidPhpDocTagValueRule.php

@@ -8,12 +8,10 @@
 use PHPStan\DependencyInjection\RegisteredRule;
 use PHPStan\DependencyInjection\ValidatesStubFiles;
 use PHPStan\Node\VirtualNode;
+use PHPStan\PhpDoc\PhpDocStringResolver;
 use PHPStan\PhpDocParser\Ast\PhpDoc\InvalidTagValueNode;
 use PHPStan\PhpDocParser\Ast\PhpDoc\TypeAliasTagValueNode;
 use PHPStan\PhpDocParser\Ast\Type\InvalidTypeNode;
-use PHPStan\PhpDocParser\Lexer\Lexer;
-use PHPStan\PhpDocParser\Parser\PhpDocParser;
-use PHPStan\PhpDocParser\Parser\TokenIterator;
 use PHPStan\Rules\MultipleNodeTypesRule;
 use PHPStan\Rules\RuleErrorBuilder;
 use function sprintf;
@@ -27,10 +25,7 @@
 final class InvalidPhpDocTagValueRule implements MultipleNodeTypesRule
 {
 
-	public function __construct(
-		private Lexer $phpDocLexer,
-		private PhpDocParser $phpDocParser,
-	)
+	public function __construct(private PhpDocStringResolver $phpDocStringResolver)
 	{
 	}
 
@@ -69,8 +64,7 @@ public function processNode(Node $node, Scope $scope): array
 		}
 
 		$phpDocString = $docComment->getText();
-		$tokens = new TokenIterator($this->phpDocLexer->tokenize($phpDocString));
-		$phpDocNode = $this->phpDocParser->parse($tokens);
+		$phpDocNode = $this->phpDocStringResolver->resolve($phpDocString);
 
 		$errors = [];
 		foreach ($phpDocNode->getTags() as $phpDocTag) {

tests/PHPStan/PhpDoc/PhpDocStringResolverTest.php

@@ -2,7 +2,9 @@
 
 namespace PHPStan\PhpDoc;
 
+use PHPStan\PhpDocParser\Lexer\Lexer;
 use PHPStan\PhpDocParser\Parser\ParserException;
+use PHPStan\PhpDocParser\Parser\PhpDocParser;
 use PHPStan\Testing\PHPStanTestCase;
 
 class PhpDocStringResolverTest extends PHPStanTestCase
@@ -17,4 +19,24 @@ public function testConsumeEnd(): void
 		$phpDocStringResolver->resolve('/** @param int $test */  test');
 	}
 
+	public function testEqualStringsShareOneNode(): void
+	{
+		$phpDocStringResolver = $this->createPhpDocStringResolver();
+
+		$node = $phpDocStringResolver->resolve('/** @param int $test */');
+		$this->assertSame($node, $phpDocStringResolver->resolve('/** @param int $test */'));
+		$this->assertNotSame($node, $phpDocStringResolver->resolve('/** @param string $test */'));
+	}
+
+	private function createPhpDocStringResolver(): PhpDocStringResolver
+	{
+		$container = self::getContainer();
+
+		return new PhpDocStringResolver(
+			$container->getByType(Lexer::class),
+			$container->getByType(PhpDocParser::class),
+			1024,
+		);
+	}
+
 }

tests/PHPStan/Rules/PhpDoc/InvalidPHPStanDocTagRuleTest.php

@@ -2,8 +2,7 @@
 
 namespace PHPStan\Rules\PhpDoc;
 
-use PHPStan\PhpDocParser\Lexer\Lexer;
-use PHPStan\PhpDocParser\Parser\PhpDocParser;
+use PHPStan\PhpDoc\PhpDocStringResolver;
 use PHPStan\Rules\Rule;
 use PHPStan\Testing\RuleTestCase;
 use PHPUnit\Framework\Attributes\RequiresPhp;
@@ -16,10 +15,8 @@ class InvalidPHPStanDocTagRuleTest extends RuleTestCase
 
 	protected function getRule(): Rule
 	{
-		$container = self::getContainer();
 		return new InvalidPHPStanDocTagRule(
-			$container->getByType(Lexer::class),
-			$container->getByType(PhpDocParser::class),
+			self::getContainer()->getByType(PhpDocStringResolver::class),
 		);
 	}
 

tests/PHPStan/Rules/PhpDoc/InvalidPhpDocTagValueRuleTest.php

@@ -2,8 +2,7 @@
 
 namespace PHPStan\Rules\PhpDoc;
 
-use PHPStan\PhpDocParser\Lexer\Lexer;
-use PHPStan\PhpDocParser\Parser\PhpDocParser;
+use PHPStan\PhpDoc\PhpDocStringResolver;
 use PHPStan\Rules\Rule;
 use PHPStan\Testing\RuleTestCase;
 use PHPUnit\Framework\Attributes\RequiresPhp;
@@ -16,10 +15,8 @@ class InvalidPhpDocTagValueRuleTest extends RuleTestCase
 
 	protected function getRule(): Rule
 	{
-		$container = self::getContainer();
 		return new InvalidPhpDocTagValueRule(
-			$container->getByType(Lexer::class),
-			$container->getByType(PhpDocParser::class),
+			self::getContainer()->getByType(PhpDocStringResolver::class),
 		);
 	}