Function that returns never is always an explicit throw point

phpstan · Sep 16, 2021 · c362fc5 · c362fc5
1 parent 24c1eb4
commit c362fc5
Show file tree

Hide file tree

Showing 3 changed files with 220 additions and 6 deletions.
diff --git a/src/Analyser/NodeScopeResolver.php b/src/Analyser/NodeScopeResolver.php
@@ -1975,7 +1975,7 @@ function (MutatingScope $scope) use ($expr, $nodeCallback, $context): Expression
 						$expr->args,
 						$methodReflection->getVariants()
 					);
-					$methodThrowPoint = $this->getMethodThrowPoint($methodReflection, $expr, $scope);
+					$methodThrowPoint = $this->getMethodThrowPoint($methodReflection, $parametersAcceptor, $expr, $scope);
 					if ($methodThrowPoint !== null) {
 						$throwPoints[] = $methodThrowPoint;
 					}
@@ -2642,8 +2642,15 @@ private function getFunctionThrowPoint(
 			return ThrowPoint::createExplicit($scope, $throwType, $funcCall, false);
 		}
 
-		if ($functionReflection->getThrowType() !== null) {
-			$throwType = $functionReflection->getThrowType();
+		$throwType = $functionReflection->getThrowType();
+		if ($throwType === null && $parametersAcceptor !== null) {
+			$returnType = $parametersAcceptor->getReturnType();
+			if ($returnType instanceof NeverType && $returnType->isExplicit()) {
+				$throwType = new ObjectType(\Throwable::class);
+			}
+		}
+
+		if ($throwType !== null) {
 			if (!$throwType instanceof VoidType) {
 				return ThrowPoint::createExplicit($scope, $throwType, $funcCall, true);
 			}
@@ -2675,7 +2682,7 @@ private function getFunctionThrowPoint(
 		return null;
 	}
 
-	private function getMethodThrowPoint(MethodReflection $methodReflection, MethodCall $methodCall, MutatingScope $scope): ?ThrowPoint
+	private function getMethodThrowPoint(MethodReflection $methodReflection, ParametersAcceptor $parametersAcceptor, MethodCall $methodCall, MutatingScope $scope): ?ThrowPoint
 	{
 		foreach ($this->dynamicThrowTypeExtensionProvider->getDynamicMethodThrowTypeExtensions() as $extension) {
 			if (!$extension->isMethodSupported($methodReflection)) {
@@ -2690,8 +2697,15 @@ private function getMethodThrowPoint(MethodReflection $methodReflection, MethodC
 			return ThrowPoint::createExplicit($scope, $throwType, $methodCall, false);
 		}
 
-		if ($methodReflection->getThrowType() !== null) {
-			$throwType = $methodReflection->getThrowType();
+		$throwType = $methodReflection->getThrowType();
+		if ($throwType === null) {
+			$returnType = $parametersAcceptor->getReturnType();
+			if ($returnType instanceof NeverType && $returnType->isExplicit()) {
+				$throwType = new ObjectType(\Throwable::class);
+			}
+		}
+
+		if ($throwType !== null) {
 			if (!$throwType instanceof VoidType) {
 				return ThrowPoint::createExplicit($scope, $throwType, $methodCall, true);
 			}

diff --git a/tests/PHPStan/Rules/Exceptions/OverwrittenExitPointByFinallyRuleTest.php b/tests/PHPStan/Rules/Exceptions/OverwrittenExitPointByFinallyRuleTest.php
@@ -85,6 +85,94 @@ public function testBug5627(): void
 				'The overwriting return is on this line.',
 				51,
 			],
+			[
+				'This throw is overwritten by a different one in the finally block below.',
+				62,
+			],
+			[
+				'This throw is overwritten by a different one in the finally block below.',
+				64,
+			],
+			[
+				'The overwriting return is on this line.',
+				66,
+			],
+			[
+				'This exit point is overwritten by a different one in the finally block below.',
+				81,
+			],
+			[
+				'This exit point is overwritten by a different one in the finally block below.',
+				83,
+			],
+			[
+				'The overwriting return is on this line.',
+				85,
+			],
+			[
+				'This exit point is overwritten by a different one in the finally block below.',
+				91,
+			],
+			[
+				'This exit point is overwritten by a different one in the finally block below.',
+				93,
+			],
+			[
+				'The overwriting return is on this line.',
+				95,
+			],
+			[
+				'This exit point is overwritten by a different one in the finally block below.',
+				101,
+			],
+			[
+				'The overwriting return is on this line.',
+				103,
+			],
+			[
+				'This throw is overwritten by a different one in the finally block below.',
+				122,
+			],
+			[
+				'This throw is overwritten by a different one in the finally block below.',
+				124,
+			],
+			[
+				'The overwriting return is on this line.',
+				126,
+			],
+			[
+				'This exit point is overwritten by a different one in the finally block below.',
+				141,
+			],
+			[
+				'This exit point is overwritten by a different one in the finally block below.',
+				143,
+			],
+			[
+				'The overwriting return is on this line.',
+				145,
+			],
+			[
+				'This exit point is overwritten by a different one in the finally block below.',
+				151,
+			],
+			[
+				'This exit point is overwritten by a different one in the finally block below.',
+				153,
+			],
+			[
+				'The overwriting return is on this line.',
+				155,
+			],
+			[
+				'This exit point is overwritten by a different one in the finally block below.',
+				161,
+			],
+			[
+				'The overwriting return is on this line.',
+				163,
+			],
 		]);
 	}
 

diff --git a/tests/PHPStan/Rules/Exceptions/data/bug-5627.php b/tests/PHPStan/Rules/Exceptions/data/bug-5627.php
@@ -53,3 +53,115 @@ public function d(): string {
 	}
 
 }
+
+class Bar
+{
+
+	public function a(): string {
+		try {
+			throw new \Exception('try');
+		} catch (\Exception $e) {
+			throw new \Exception('catch');
+		} finally {
+			return 'finally';
+		}
+	}
+
+	/**
+	 *
+	 * @return never
+	 */
+	public function abort()
+	{
+		throw new \Exception();
+	}
+
+	public function b(): string {
+		try {
+			$this->abort();
+		} catch (\Exception $e) {
+			$this->abort();
+		} finally {
+			return 'finally';
+		}
+	}
+
+	public function c(): string {
+		try {
+			$this->abort();
+		} catch (\Throwable $e) {
+			$this->abort();
+		} finally {
+			return 'finally';
+		}
+	}
+
+	public function d(): string {
+		try {
+			$this->abort();
+		} finally {
+			return 'finally';
+		}
+	}
+
+}
+
+/**
+ * @return never
+ */
+function abort()
+{
+
+}
+
+class Baz
+{
+
+	public function a(): string {
+		try {
+			throw new \Exception('try');
+		} catch (\Exception $e) {
+			throw new \Exception('catch');
+		} finally {
+			return 'finally';
+		}
+	}
+
+
+
+
+
+
+
+
+
+
+	public function b(): string {
+		try {
+			abort();
+		} catch (\Exception $e) {
+			abort();
+		} finally {
+			return 'finally';
+		}
+	}
+
+	public function c(): string {
+		try {
+			abort();
+		} catch (\Throwable $e) {
+			abort();
+		} finally {
+			return 'finally';
+		}
+	}
+
+	public function d(): string {
+		try {
+			abort();
+		} finally {
+			return 'finally';
+		}
+	}
+
+}