RuleErrorFilterExtension

This allows for more flexibility in filtering errors.

Some use cases:

* Ignore `missingType.iterableValue` on controller actions:
  Rule: when the method is public and it has `#[Route]` attribute or the
        class has `#[AsController]` attribute.
* Ignore `should return int but returns int|null` on `getId` for entities.
  Rule: class needs to have `#[Entity]` attribute.
* Ignore `never returns null so it can be removed from the return type`
  Rule: method needs to have `#[GraphQL\Field]` attribute.

Author: ruudk

src/Analyser/AnalyserResultFinalizer.php

@@ -19,6 +19,7 @@ final class AnalyserResultFinalizer
 
 	public function __construct(
 		private RuleRegistry $ruleRegistry,
+		private RuleErrorFilter $ruleErrorFilter,
 		private RuleErrorTransformer $ruleErrorTransformer,
 		private ScopeFactory $scopeFactory,
 		private LocalIgnoresProcessor $localIgnoresProcessor,
@@ -87,6 +88,8 @@ public function finalize(AnalyserResult $analyserResult, bool $onlyFiles, bool $
 				continue;
 			}
 
+			$ruleErrors = $this->ruleErrorFilter->filter($ruleErrors, $node, $scope);
+
 			foreach ($ruleErrors as $ruleError) {
 				$tempCollectorErrors[] = $this->ruleErrorTransformer->transform($ruleError, $scope, $nodeType, $node->getStartLine());
 			}

src/Analyser/FileAnalyser.php

@@ -51,6 +51,7 @@ public function __construct(
 		private NodeScopeResolver $nodeScopeResolver,
 		private Parser $parser,
 		private DependencyResolver $dependencyResolver,
+		private RuleErrorFilter $ruleErrorFilter,
 		private RuleErrorTransformer $ruleErrorTransformer,
 		private LocalIgnoresProcessor $localIgnoresProcessor,
 	)
@@ -141,6 +142,8 @@ public function analyseFile(
 							continue;
 						}
 
+						$ruleErrors = $this->ruleErrorFilter->filter($ruleErrors, $node, $scope);
+
 						foreach ($ruleErrors as $ruleError) {
 							$temporaryFileErrors[] = $this->ruleErrorTransformer->transform($ruleError, $scope, $nodeType, $node->getStartLine());
 						}

src/Analyser/RuleErrorFilter.php

@@ -0,0 +1,51 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Analyser;
+
+use PhpParser\Node;
+use PHPStan\DependencyInjection\Container;
+use PHPStan\Rules\RuleError;
+use PHPStan\Rules\RuleErrorFilterExtension;
+
+final class RuleErrorFilter
+{
+
+	public function __construct(private Container $container)
+	{
+	}
+
+	/**
+	 * @param RuleError[] $ruleErrors
+	 * @return RuleError[]
+	 */
+	public function filter(
+		array $ruleErrors,
+		Node $node,
+		Scope $scope,
+	): array
+	{
+		if ($ruleErrors === []) {
+			return [];
+		}
+
+		$extensions = $this->container->getServicesByTag(RuleErrorFilterExtension::EXTENSION_TAG);
+
+		foreach ($extensions as $extension) {
+			if (!$extension instanceof RuleErrorFilterExtension) {
+				continue;
+			}
+
+			$ruleErrors = array_filter(
+				$ruleErrors,
+				static fn (RuleError $ruleError): bool => !$extension->filter($ruleError, $node, $scope)
+			);
+
+			if ($ruleErrors === []) {
+				break;
+			}
+		}
+
+		return $ruleErrors;
+	}
+
+}

src/Rules/RuleErrorFilterExtension.php

@@ -0,0 +1,33 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Rules;
+
+use PHPStan\Analyser\Scope;
+use PhpParser\Node;
+
+/**
+ * This is the extension interface to implement if you want to filter out rule
+ * errors based on the node and scope.
+ *
+ * To register it in the configuration file use the `phpstan.ruleErrorFilterExtension` service tag:
+ *
+ * ```
+ * services:
+ * 	-
+ *		class: App\PHPStan\MyExtension
+ *		tags:
+ *			- phpstan.ruleErrorFilterExtension
+ * ```
+ *
+ * Learn more: https://phpstan.org
+ *
+ * @api
+ */
+interface RuleErrorFilterExtension
+{
+
+	public const EXTENSION_TAG = 'phpstan.ruleErrorFilterExtension';
+
+	public function filter(RuleError $ruleError, Node $node, Scope $scope): bool;
+
+}