Introduce reportArrayKeyCast parameter

conf/config.neon

@@ -76,6 +76,7 @@ parameters:
 	reportStaticMethodSignatures: false
 	reportWrongPhpDocTypeInVarTag: false
 	reportAnyTypeWideningInVarTag: false
+	allowFloatBoolNullAsArrayKey: true
 	reportPossiblyNonexistentGeneralArrayOffset: false
 	reportPossiblyNonexistentConstantArrayOffset: false
 	checkMissingOverrideMethodAttribute: false

conf/parametersSchema.neon

@@ -85,6 +85,7 @@ parametersSchema:
 	reportStaticMethodSignatures: bool()
 	reportWrongPhpDocTypeInVarTag: bool()
 	reportAnyTypeWideningInVarTag: bool()
+	allowFloatBoolNullAsArrayKey: bool()
 	reportPossiblyNonexistentGeneralArrayOffset: bool()
 	reportPossiblyNonexistentConstantArrayOffset: bool()
 	checkMissingOverrideMethodAttribute: bool()

src/Rules/Arrays/AllowedArrayKeysTypes.php

@@ -22,19 +22,22 @@
 final class AllowedArrayKeysTypes
 {
 
-	public static function getType(?PhpVersion $phpVersion = null): Type
+	public static function getType(?PhpVersion $phpVersion = null, bool $allowFloatBoolNull = true): Type
 	{
 		$types = [
 			new IntegerType(),
 			new StringType(),
-			new BooleanType(),
 		];
 
-		if ($phpVersion === null || !$phpVersion->deprecatesImplicitlyFloatConversionToInt()) {
-			$types[] = new FloatType();
-		}
-		if ($phpVersion === null || !$phpVersion->deprecatesNullArrayOffset()) {
-			$types[] = new NullType();
+		if ($allowFloatBoolNull) {
+			$types[] = new BooleanType();
+
+			if ($phpVersion === null || !$phpVersion->deprecatesImplicitlyFloatConversionToInt()) {
+				$types[] = new FloatType();
+			}
+			if ($phpVersion === null || !$phpVersion->deprecatesNullArrayOffset()) {
+				$types[] = new NullType();
+			}
 		}
 
 		return new UnionType($types);

src/Rules/Arrays/InvalidKeyInArrayDimFetchRule.php

@@ -27,6 +27,8 @@ public function __construct(
 		private PhpVersion $phpVersion,
 		#[AutowiredParameter]
 		private bool $reportMaybes,
+		#[AutowiredParameter]
+		private bool $allowFloatBoolNullAsArrayKey,
 	)
 	{
 	}
@@ -59,17 +61,18 @@ public function processNode(Node $node, Scope $scope): array
 		}
 
 		$phpVersion = $this->phpVersion;
+		$allowFloatBoolNullAsArrayKey = $this->allowFloatBoolNullAsArrayKey;
 		$dimensionType = $this->ruleLevelHelper->findTypeToCheck(
 			$scope,
 			$node->dim,
 			'',
-			static fn (Type $dimType): bool => AllowedArrayKeysTypes::getType($phpVersion)->isSuperTypeOf($dimType)->yes(),
+			static fn (Type $dimType): bool => AllowedArrayKeysTypes::getType($phpVersion, $allowFloatBoolNullAsArrayKey)->isSuperTypeOf($dimType)->yes(),
 		)->getType();
 		if ($dimensionType instanceof ErrorType) {
 			return [];
 		}
 
-		$isSuperType = AllowedArrayKeysTypes::getType($phpVersion)->isSuperTypeOf($dimensionType);
+		$isSuperType = AllowedArrayKeysTypes::getType($phpVersion, $allowFloatBoolNullAsArrayKey)->isSuperTypeOf($dimensionType);
 		if ($isSuperType->yes() || ($isSuperType->maybe() && !$this->reportMaybes)) {
 			return [];
 		}

src/Rules/Arrays/InvalidKeyInArrayItemRule.php

@@ -4,6 +4,7 @@
 
 use PhpParser\Node;
 use PHPStan\Analyser\Scope;
+use PHPStan\DependencyInjection\AutowiredParameter;
 use PHPStan\DependencyInjection\RegisteredRule;
 use PHPStan\Php\PhpVersion;
 use PHPStan\Rules\Rule;
@@ -24,6 +25,8 @@ final class InvalidKeyInArrayItemRule implements Rule
 	public function __construct(
 		private RuleLevelHelper $ruleLevelHelper,
 		private PhpVersion $phpVersion,
+		#[AutowiredParameter]
+		private bool $allowFloatBoolNullAsArrayKey,
 	)
 	{
 	}
@@ -40,17 +43,18 @@ public function processNode(Node $node, Scope $scope): array
 		}
 
 		$phpVersion = $this->phpVersion;
+		$allowFloatBoolNullAsArrayKey = $this->allowFloatBoolNullAsArrayKey;
 		$dimensionType = $this->ruleLevelHelper->findTypeToCheck(
 			$scope,
 			$node->key,
 			'',
-			static fn (Type $dimType): bool => AllowedArrayKeysTypes::getType($phpVersion)->isSuperTypeOf($dimType)->yes(),
+			static fn (Type $dimType): bool => AllowedArrayKeysTypes::getType($phpVersion, $allowFloatBoolNullAsArrayKey)->isSuperTypeOf($dimType)->yes(),
 		)->getType();
 		if ($dimensionType instanceof ErrorType) {
 			return [];
 		}
 
-		$isSuperType = AllowedArrayKeysTypes::getType($phpVersion)->isSuperTypeOf($dimensionType);
+		$isSuperType = AllowedArrayKeysTypes::getType($phpVersion, $allowFloatBoolNullAsArrayKey)->isSuperTypeOf($dimensionType);
 		if ($isSuperType->yes()) {
 			return [];
 		}

tests/PHPStan/Rules/Arrays/InvalidKeyInArrayDimFetchRuleTest.php

@@ -15,13 +15,16 @@
 class InvalidKeyInArrayDimFetchRuleTest extends RuleTestCase
 {
 
+	private bool $allowFloatBoolNullAsArrayKey = true;
+
 	protected function getRule(): Rule
 	{
 		$ruleLevelHelper = new RuleLevelHelper(self::createReflectionProvider(), true, false, true, true, true, false, true);
 		return new InvalidKeyInArrayDimFetchRule(
 			$ruleLevelHelper,
 			self::getContainer()->getByType(PhpVersion::class),
 			true,
+			$this->allowFloatBoolNullAsArrayKey,
 		);
 	}
 
@@ -163,4 +166,20 @@ public function testBug12981(): void
 		]);
 	}
 
+	public function testUnsetFalseKey(): void
+	{
+		$this->allowFloatBoolNullAsArrayKey = false;
+
+		$this->analyse([__DIR__ . '/data/unset-false-key.php'], [
+			[
+				'Invalid array key type false.',
+				6,
+			],
+			[
+				'Invalid array key type false.',
+				13,
+			],
+		]);
+	}
+
 }

tests/PHPStan/Rules/Arrays/InvalidKeyInArrayItemRuleTest.php

@@ -15,6 +15,8 @@
 class InvalidKeyInArrayItemRuleTest extends RuleTestCase
 {
 
+	private bool $allowFloatBoolNullAsArrayKey = true;
+
 	private bool $checkExplicitMixed = false;
 
 	private bool $checkImplicitMixed = false;
@@ -26,6 +28,7 @@ protected function getRule(): Rule
 		return new InvalidKeyInArrayItemRule(
 			$ruleLevelHelper,
 			self::getContainer()->getByType(PhpVersion::class),
+			$this->allowFloatBoolNullAsArrayKey,
 		);
 	}
 
@@ -102,6 +105,38 @@ public function testInvalidMixedKey(): void
 		$this->analyse([__DIR__ . '/data/invalid-key-array-item.php'], $errors);
 	}
 
+	public function testInvalidKeyReportingCastedArrayKey(): void
+	{
+		$this->allowFloatBoolNullAsArrayKey = false;
+
+		$this->analyse([__DIR__ . '/data/invalid-key-array-item.php'], [
+			[
+				'Invalid array key type DateTimeImmutable.',
+				12,
+			],
+			[
+				'Invalid array key type array.',
+				13,
+			],
+			[
+				'Possibly invalid array key type stdClass|string.',
+				14,
+			],
+			[
+				'Invalid array key type float.',
+				26,
+			],
+			[
+				'Invalid array key type null.',
+				27,
+			],
+			[
+				'Invalid array key type false.',
+				31,
+			],
+		]);
+	}
+
 	public function testInvalidKeyInList(): void
 	{
 		$this->analyse([__DIR__ . '/data/invalid-key-list.php'], [

tests/PHPStan/Rules/Arrays/data/invalid-key-array-item.php

@@ -26,3 +26,7 @@
 	1.0 => 'aaa',
 	null => 'aaa',
 ];
+
+$d = [
+	false => 'aaa',
+];

tests/PHPStan/Rules/Arrays/data/unset-false-key.php

@@ -0,0 +1,16 @@
+<?php declare(strict_types=1);
+
+namespace UnsetFalseKey;
+
+/** @var array<int, int> $data */
+unset($data[false]);
+
+function test_remove_element(): void {
+	$modified = [1, 4, 6, 8];
+
+	// this would happen in the SUT
+	unset($modified[array_search(4, $modified, true)]);
+	unset($modified[array_search(5, $modified, true)]); // bug is here - will unset key `0` by accident
+
+	assert([1, 6, 8] === $modified); // actually is [6, 8]
+}