Add support for PHP 8.5 #[\NoDiscard]

Co-authored-by: Ondrej Mirtes <ondrej@mirtes.cz>

Author: DanielEScherzer

.github/workflows/lint.yml

@@ -135,7 +135,7 @@ jobs:
         uses: "shivammathur/setup-php@v2"
         with:
           coverage: "none"
-          php-version: "8.4"
+          php-version: "8.5"
 
       - name: "Install dependencies"
         run: "composer install --no-interaction --no-progress"

Makefile

@@ -110,6 +110,12 @@ lint:
 		--exclude tests/PHPStan/Rules/Classes/data/enum-cannot-be-attribute.php \
 		--exclude tests/PHPStan/Rules/Classes/data/class-attributes.php \
 		--exclude tests/PHPStan/Rules/Classes/data/enum-attributes.php \
+		--exclude tests/PHPStan/Rules/Cast/data/void-cast.php \
+		--exclude tests/PHPStan/Rules/Properties/data/property-hook-attributes-nodiscard.php \
+		--exclude tests/PHPStan/Rules/Functions/data/arrow-function-typehints-nodiscard.php \
+		--exclude tests/PHPStan/Rules/Functions/data/closure-typehints-nodiscard.php \
+		--exclude tests/PHPStan/Rules/Functions/data/typehints-nodiscard.php \
+		--exclude tests/PHPStan/Rules/Methods/data/typehints-nodiscard.php \
 		src tests
 
 install-paratest:

build/collision-detector.json

@@ -15,6 +15,7 @@
 		"../tests/PHPStan/Rules/Functions/data/define-bug-3349.php",
 		"../tests/PHPStan/Levels/data/stubs/function.php",
 		"../tests/PHPStan/Rules/Properties/data/abstract-final-property-hook-parse-error.php",
-		"../tests/PHPStan/Rules/Properties/data/final-property-hooks.php"
+		"../tests/PHPStan/Rules/Properties/data/final-property-hooks.php",
+		"../tests/PHPStan/Rules/Cast/data/void-cast.php"
     ]
 }

src/Analyser/MutatingScope.php

@@ -1442,6 +1442,16 @@ static function (Node $node, Scope $scope) use ($arrowScope, &$arrowFunctionImpu
 				if (array_key_exists($cacheKey, $cachedTypes)) {
 					$cachedClosureData = $cachedTypes[$cacheKey];
 
+					$mustUseReturnValue = TrinaryLogic::createNo();
+					foreach ($node->attrGroups as $attrGroup) {
+						foreach ($attrGroup->attrs as $attr) {
+							if ($attr->name->toLowerString() === 'nodiscard') {
+								$mustUseReturnValue = TrinaryLogic::createYes();
+								break;
+							}
+						}
+					}
+
 					return new ClosureType(
 						$parameters,
 						$cachedClosureData['returnType'],
@@ -1454,6 +1464,7 @@ static function (Node $node, Scope $scope) use ($arrowScope, &$arrowFunctionImpu
 						invalidateExpressions: $cachedClosureData['invalidateExpressions'],
 						usedVariables: $cachedClosureData['usedVariables'],
 						acceptsNamedArguments: TrinaryLogic::createYes(),
+						mustUseReturnValue: $mustUseReturnValue,
 					);
 				}
 				if (self::$resolveClosureTypeDepth >= 2) {
@@ -1656,6 +1667,16 @@ static function (Node $node, Scope $scope) use ($arrowScope, &$arrowFunctionImpu
 			];
 			$node->setAttribute('phpstanCachedTypes', $cachedTypes);
 
+			$mustUseReturnValue = TrinaryLogic::createNo();
+			foreach ($node->attrGroups as $attrGroup) {
+				foreach ($attrGroup->attrs as $attr) {
+					if ($attr->name->toLowerString() === 'nodiscard') {
+						$mustUseReturnValue = TrinaryLogic::createYes();
+						break;
+					}
+				}
+			}
+
 			return new ClosureType(
 				$parameters,
 				$returnType,
@@ -1668,6 +1689,7 @@ static function (Node $node, Scope $scope) use ($arrowScope, &$arrowFunctionImpu
 				invalidateExpressions: $invalidateExpressions,
 				usedVariables: $usedVariables,
 				acceptsNamedArguments: TrinaryLogic::createYes(),
+				mustUseReturnValue: $mustUseReturnValue,
 			);
 		} elseif ($node instanceof New_) {
 			if ($node->class instanceof Name) {
@@ -2716,10 +2738,12 @@ private function createFirstClassCallable(
 			$throwPoints = [];
 			$impurePoints = [];
 			$acceptsNamedArguments = TrinaryLogic::createYes();
+			$mustUseReturnValue = TrinaryLogic::createMaybe();
 			if ($variant instanceof CallableParametersAcceptor) {
 				$throwPoints = $variant->getThrowPoints();
 				$impurePoints = $variant->getImpurePoints();
 				$acceptsNamedArguments = $variant->acceptsNamedArguments();
+				$mustUseReturnValue = $variant->mustUseReturnValue();
 			} elseif ($function !== null) {
 				$returnTypeForThrow = $variant->getReturnType();
 				$throwType = $function->getThrowType();
@@ -2745,6 +2769,7 @@ private function createFirstClassCallable(
 				}
 
 				$acceptsNamedArguments = $function->acceptsNamedArguments();
+				$mustUseReturnValue = $function->mustUseReturnValue();
 			}
 
 			$parameters = $variant->getParameters();
@@ -2759,6 +2784,7 @@ private function createFirstClassCallable(
 				$throwPoints,
 				$impurePoints,
 				acceptsNamedArguments: $acceptsNamedArguments,
+				mustUseReturnValue: $mustUseReturnValue,
 			);
 		}
 

src/PhpDoc/TypeNodeResolver.php

@@ -1032,7 +1032,7 @@ function (CallableTypeParameterNode $parameterNode) use ($nameScope, &$isVariadi
 				),
 			]);
 		} elseif ($mainType instanceof ClosureType) {
-			$closure = new ClosureType($parameters, $returnType, $isVariadic, $templateTypeMap, templateTags: $templateTags, impurePoints: $mainType->getImpurePoints(), invalidateExpressions: $mainType->getInvalidateExpressions(), usedVariables: $mainType->getUsedVariables(), acceptsNamedArguments: $mainType->acceptsNamedArguments());
+			$closure = new ClosureType($parameters, $returnType, $isVariadic, $templateTypeMap, templateTags: $templateTags, impurePoints: $mainType->getImpurePoints(), invalidateExpressions: $mainType->getInvalidateExpressions(), usedVariables: $mainType->getUsedVariables(), acceptsNamedArguments: $mainType->acceptsNamedArguments(), mustUseReturnValue: $mainType->mustUseReturnValue());
 			if ($closure->isPure()->yes() && $returnType->isVoid()->yes()) {
 				return new ErrorType();
 			}

src/Reflection/Annotations/AnnotationMethodReflection.php

@@ -183,4 +183,9 @@ public function getAttributes(): array
 		return [];
 	}
 
+	public function mustUseReturnValue(): TrinaryLogic
+	{
+		return TrinaryLogic::createNo();
+	}
+
 }

src/Reflection/Callables/CallableParametersAcceptor.php

@@ -36,4 +36,11 @@ public function getInvalidateExpressions(): array;
 	 */
 	public function getUsedVariables(): array;
 
+	/**
+	 * Has the #[\NoDiscard] attribute - on PHP 8.5+ if the function's return
+	 * value is unused at runtime a warning is emitted, PHPStan will emit the
+	 * warning during analysis and on older PHP versions too
+	 */
+	public function mustUseReturnValue(): TrinaryLogic;
+
 }

src/Reflection/Callables/FunctionCallableVariant.php

@@ -168,4 +168,9 @@ public function acceptsNamedArguments(): TrinaryLogic
 		return $this->function->acceptsNamedArguments();
 	}
 
+	public function mustUseReturnValue(): TrinaryLogic
+	{
+		return $this->function->mustUseReturnValue();
+	}
+
 }

src/Reflection/Dummy/ChangedTypeMethodReflection.php

@@ -172,4 +172,9 @@ public function getAttributes(): array
 		return $this->reflection->getAttributes();
 	}
 
+	public function mustUseReturnValue(): TrinaryLogic
+	{
+		return $this->reflection->mustUseReturnValue();
+	}
+
 }

src/Reflection/Dummy/DummyConstructorReflection.php

@@ -157,4 +157,10 @@ public function getAttributes(): array
 		return [];
 	}
 
+	public function mustUseReturnValue(): TrinaryLogic
+	{
+		// Align with the getAttributes() returning empty
+		return TrinaryLogic::createNo();
+	}
+
 }