strtok() always returns a non-empty-string when it does not return false

staabm · ondrejmirtes · commit 9463e66359b3 · 2024-01-14T16:45:22.000+01:00
diff --git a/resources/functionMap.php b/resources/functionMap.php
@@ -12083,8 +12083,8 @@
 'strrpos' => ['0|positive-int|false', 'haystack'=>'string', 'needle'=>'string|int', 'offset='=>'int'],
 'strspn' => ['int', 'str'=>'string', 'mask'=>'string', 'start='=>'int', 'len='=>'int'],
 'strstr' => ['string|false', 'haystack'=>'string', 'needle'=>'mixed', 'before_needle='=>'bool'],
-'strtok' => ['string|false', 'str'=>'string', 'token'=>'string'],
-'strtok\'1' => ['string|false', 'token'=>'string'],
+'strtok' => ['non-empty-string|false', 'str'=>'string', 'token'=>'string'],
+'strtok\'1' => ['non-empty-string|false', 'token'=>'string'],
 'strtolower' => ['string', 'str'=>'string'],
 'strtotime' => ['int|false', 'time'=>'string', 'now='=>'int'],
 'strtoupper' => ['string', 'str'=>'string'],
diff --git a/src/Type/Php/StrTokFunctionReturnTypeExtension.php b/src/Type/Php/StrTokFunctionReturnTypeExtension.php
@@ -5,10 +5,11 @@
 use PhpParser\Node\Expr\FuncCall;
 use PHPStan\Analyser\Scope;
 use PHPStan\Reflection\FunctionReflection;
-use PHPStan\Reflection\ParametersAcceptorSelector;
+use PHPStan\Type\Accessory\AccessoryNonEmptyStringType;
 use PHPStan\Type\Constant\ConstantBooleanType;
 use PHPStan\Type\Constant\ConstantStringType;
 use PHPStan\Type\DynamicFunctionReturnTypeExtension;
+use PHPStan\Type\IntersectionType;
 use PHPStan\Type\StringType;
 use PHPStan\Type\Type;
 use function count;
@@ -21,11 +22,11 @@ public function isFunctionSupported(FunctionReflection $functionReflection): boo
 		return $functionReflection->getName() === 'strtok';
 	}
 
-	public function getTypeFromFunctionCall(FunctionReflection $functionReflection, FuncCall $functionCall, Scope $scope): Type
+	public function getTypeFromFunctionCall(FunctionReflection $functionReflection, FuncCall $functionCall, Scope $scope): ?Type
 	{
 		$args = $functionCall->getArgs();
 		if (count($args) !== 2) {
-			return ParametersAcceptorSelector::selectFromArgs($scope, $args, $functionReflection->getVariants())->getReturnType();
+			return null;
 		}
 
 		$delimiterType = $scope->getType($functionCall->getArgs()[0]->value);
@@ -35,10 +36,10 @@ public function getTypeFromFunctionCall(FunctionReflection $functionReflection,
 		}
 
 		if ($isEmptyString->no()) {
-			return new StringType();
+			return new IntersectionType([new StringType(), new AccessoryNonEmptyStringType()]);
 		}
 
-		return ParametersAcceptorSelector::selectFromArgs($scope, $args, $functionReflection->getVariants())->getReturnType();
+		return null;
 	}
 
 }
diff --git a/tests/PHPStan/Analyser/data/bug-3981.php b/tests/PHPStan/Analyser/data/bug-3981.php
@@ -13,8 +13,8 @@ class Foo
 	 */
 	public function doFoo(string $s, string $nonEmptyString): void
 	{
-		assertType('string|false', strtok($s, ' '));
-		assertType('string', strtok($nonEmptyString, ' '));
+		assertType('non-empty-string|false', strtok($s, ' '));
+		assertType('non-empty-string', strtok($nonEmptyString, ' '));
 		assertType('false', strtok('', ' '));
 
 		assertType('non-empty-string', $nonEmptyString[0]);
diff --git a/tests/PHPStan/Reflection/ParametersAcceptorSelectorTest.php b/tests/PHPStan/Reflection/ParametersAcceptorSelectorTest.php
@@ -9,6 +9,7 @@
 use PHPStan\Reflection\Native\NativeParameterReflection;
 use PHPStan\Reflection\Php\DummyParameter;
 use PHPStan\Testing\PHPStanTestCase;
+use PHPStan\Type\Accessory\AccessoryNonEmptyStringType;
 use PHPStan\Type\ArrayType;
 use PHPStan\Type\Constant\ConstantBooleanType;
 use PHPStan\Type\Constant\ConstantIntegerType;
@@ -18,6 +19,7 @@
 use PHPStan\Type\Generic\TemplateTypeScope;
 use PHPStan\Type\Generic\TemplateTypeVariance;
 use PHPStan\Type\IntegerType;
+use PHPStan\Type\IntersectionType;
 use PHPStan\Type\MixedType;
 use PHPStan\Type\NullType;
 use PHPStan\Type\ObjectType;
@@ -198,7 +200,7 @@ public function dataSelectFromTypes(): Generator
 					),
 				],
 				false,
-				new UnionType([new StringType(), new ConstantBooleanType(false)]),
+				new UnionType([new IntersectionType([new StringType(), new AccessoryNonEmptyStringType()]), new ConstantBooleanType(false)]),
 			),
 		];
 		yield [

Original file line number	Diff line number	Diff line change
`@@ -5,10 +5,11 @@`
`5`	`5`	`use PhpParser\Node\Expr\FuncCall;`
`6`	`6`	`use PHPStan\Analyser\Scope;`
`7`	`7`	`use PHPStan\Reflection\FunctionReflection;`
`8`		`-use PHPStan\Reflection\ParametersAcceptorSelector;`
	`8`	`+use PHPStan\Type\Accessory\AccessoryNonEmptyStringType;`
`9`	`9`	`use PHPStan\Type\Constant\ConstantBooleanType;`
`10`	`10`	`use PHPStan\Type\Constant\ConstantStringType;`
`11`	`11`	`use PHPStan\Type\DynamicFunctionReturnTypeExtension;`
	`12`	`+use PHPStan\Type\IntersectionType;`
`12`	`13`	`use PHPStan\Type\StringType;`
`13`	`14`	`use PHPStan\Type\Type;`
`14`	`15`	`use function count;`
`@@ -21,11 +22,11 @@ public function isFunctionSupported(FunctionReflection $functionReflection): boo`
`21`	`22`	`return $functionReflection->getName() === 'strtok';`
`22`	`23`	`}`
`23`	`24`
`24`		`- public function getTypeFromFunctionCall(FunctionReflection $functionReflection, FuncCall $functionCall, Scope $scope): Type`
	`25`	`+ public function getTypeFromFunctionCall(FunctionReflection $functionReflection, FuncCall $functionCall, Scope $scope): ?Type`
`25`	`26`	`{`
`26`	`27`	`$args = $functionCall->getArgs();`
`27`	`28`	`if (count($args) !== 2) {`
`28`		`- return ParametersAcceptorSelector::selectFromArgs($scope, $args, $functionReflection->getVariants())->getReturnType();`
	`29`	`+ return null;`
`29`	`30`	`}`
`30`	`31`
`31`	`32`	`$delimiterType = $scope->getType($functionCall->getArgs()[0]->value);`
`@@ -35,10 +36,10 @@ public function getTypeFromFunctionCall(FunctionReflection $functionReflection,`
`35`	`36`	`}`
`36`	`37`
`37`	`38`	`if ($isEmptyString->no()) {`
`38`		`- return new StringType();`
	`39`	`+ return new IntersectionType([new StringType(), new AccessoryNonEmptyStringType()]);`
`39`	`40`	`}`
`40`	`41`
`41`		`- return ParametersAcceptorSelector::selectFromArgs($scope, $args, $functionReflection->getVariants())->getReturnType();`
	`42`	`+ return null;`
`42`	`43`	`}`
`43`	`44`
`44`	`45`	`}`