Check continue/break outside of loop and switch (level 0)

build.xml

@@ -137,6 +137,8 @@
 			<arg path="tests/PHPStan/Rules/Functions/data/arrow-function-nullsafe-by-ref.php"/>
 			<arg value="--exclude"/>
 			<arg path="tests/PHPStan/Levels/data/namedArguments.php"/>
+			<arg value="--exclude"/>
+			<arg path="tests/PHPStan/Rules/Keywords/data/continue-break.php"/>
 			<arg path="src" />
 			<arg path="tests" />
 			<arg path="compiler/src" />

conf/config.level0.neon

@@ -46,6 +46,7 @@ rules:
 	- PHPStan\Rules\Functions\ParamAttributesRule
 	- PHPStan\Rules\Functions\PrintfParametersRule
 	- PHPStan\Rules\Functions\ReturnNullsafeByRefRule
+	- PHPStan\Rules\Keywords\ContinueBreakInLoopRule
 	- PHPStan\Rules\Methods\AbstractMethodInNonAbstractClassRule
 	- PHPStan\Rules\Methods\ExistingClassesInTypehintsRule
 	- PHPStan\Rules\Methods\MissingMethodImplementationRule

src/Rules/Keywords/ContinueBreakInLoopRule.php

@@ -0,0 +1,71 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Rules\Keywords;
+
+use PhpParser\Node;
+use PhpParser\Node\Stmt;
+use PHPStan\Analyser\Scope;
+use PHPStan\Rules\Rule;
+use PHPStan\Rules\RuleErrorBuilder;
+
+/**
+ * @implements Rule<Stmt>
+ */
+class ContinueBreakInLoopRule implements Rule
+{
+
+	public function getNodeType(): string
+	{
+		return Stmt::class;
+	}
+
+	public function processNode(Node $node, Scope $scope): array
+	{
+		if (!$node instanceof Stmt\Continue_ && !$node instanceof Stmt\Break_) {
+			return [];
+		}
+
+		if (!$node->num instanceof Node\Scalar\LNumber) {
+			$value = 1;
+		} else {
+			$value = $node->num->value;
+		}
+
+		$parent = $node->getAttribute('parent');
+		while ($value > 0) {
+			if (
+				$parent === null
+				|| $parent instanceof Stmt\Function_
+				|| $parent instanceof Stmt\ClassMethod
+				|| $parent instanceof Node\Expr\Closure
+			) {
+				return [
+					RuleErrorBuilder::message(sprintf(
+						'Keyword %s used outside of a loop or a switch statement.',
+						$node instanceof Stmt\Continue_ ? 'continue' : 'break'
+					))->nonIgnorable()->build(),
+				];
+			}
+			if (
+				$parent instanceof Stmt\For_
+				|| $parent instanceof Stmt\Foreach_
+				|| $parent instanceof Stmt\Do_
+				|| $parent instanceof Stmt\While_
+			) {
+				$value--;
+			}
+			if ($parent instanceof Stmt\Case_) {
+				$value--;
+				$parent = $parent->getAttribute('parent');
+				if (!$parent instanceof Stmt\Switch_) {
+					throw new \PHPStan\ShouldNotHappenException();
+				}
+			}
+
+			$parent = $parent->getAttribute('parent');
+		}
+
+		return [];
+	}
+
+}

tests/PHPStan/Rules/Keywords/ContinueBreakInLoopRuleTest.php

@@ -0,0 +1,52 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Rules\Keywords;
+
+use PHPStan\Testing\RuleTestCase;
+
+/**
+ * @extends RuleTestCase<ContinueBreakInLoopRule>
+ */
+class ContinueBreakInLoopRuleTest extends RuleTestCase
+{
+
+	protected function getRule(): \PHPStan\Rules\Rule
+	{
+		return new ContinueBreakInLoopRule();
+	}
+
+	public function testRule(): void
+	{
+		if (!self::$useStaticReflectionProvider) {
+			$this->markTestSkipped('Test requires static reflection.');
+		}
+
+		$this->analyse([__DIR__ . '/data/continue-break.php'], [
+			[
+				'Keyword break used outside of a loop or a switch statement.',
+				67,
+			],
+			[
+				'Keyword break used outside of a loop or a switch statement.',
+				69,
+			],
+			[
+				'Keyword break used outside of a loop or a switch statement.',
+				77,
+			],
+			[
+				'Keyword continue used outside of a loop or a switch statement.',
+				79,
+			],
+			[
+				'Keyword break used outside of a loop or a switch statement.',
+				87,
+			],
+			[
+				'Keyword break used outside of a loop or a switch statement.',
+				95,
+			],
+		]);
+	}
+
+}

tests/PHPStan/Rules/Keywords/data/continue-break.php

@@ -0,0 +1,96 @@
+<?php
+
+namespace ContinueBreak;
+
+class Foo
+{
+
+	public function doFoo($foo): void
+	{
+		switch ($foo) {
+			case 1:
+				break;
+			default:
+				break;
+		}
+
+		foreach ([1, 2, 3] as $val) {
+			if (rand(0, 1)) {
+				break;
+			} else {
+				continue;
+			}
+		}
+
+		for ($i = 0; $i < 5; $i++) {
+			if (rand(0, 1)) {
+				break;
+			} else {
+				continue;
+			}
+		}
+
+		while (true) {
+			if (rand(0, 1)) {
+				break;
+			} else {
+				continue;
+			}
+		}
+
+		do {
+			if (rand(0, 1)) {
+				break;
+			} else {
+				continue;
+			}
+		} while (true);
+	}
+
+	public function doLorem($foo)
+	{
+		foreach ([1, 2, 3] as $val) {
+			switch ($foo) {
+				case 1:
+					break 2;
+				default:
+					break 2;
+			}
+		}
+	}
+
+	public function doBar($foo)
+	{
+		foreach ([1, 2, 3] as $val) {
+			switch ($foo) {
+				case 1:
+					break 3;
+				default:
+					break 3;
+			}
+		}
+	}
+
+	public function doBaz()
+	{
+		if (rand(0, 1)) {
+			break;
+		} else {
+			continue;
+		}
+	}
+
+	public function doIpsum($foo)
+	{
+		foreach ([1, 2, 3] as $val) {
+			function (): void {
+				break;
+			};
+		}
+	}
+
+}
+
+if (rand(0, 1)) {
+	break;
+}