min() and max() may return false if array size could be zero

dktapps · web-flow · commit ad7dce2bc830 · 2020-08-16T19:28:56.000+02:00
diff --git a/src/Type/Php/MinMaxFunctionReturnTypeExtension.php b/src/Type/Php/MinMaxFunctionReturnTypeExtension.php
@@ -7,6 +7,7 @@
 use PHPStan\Reflection\FunctionReflection;
 use PHPStan\Reflection\ParametersAcceptorSelector;
 use PHPStan\Type\Constant\ConstantArrayType;
+use PHPStan\Type\Constant\ConstantBooleanType;
 use PHPStan\Type\ConstantScalarType;
 use PHPStan\Type\ConstantType;
 use PHPStan\Type\ErrorType;
@@ -37,8 +38,15 @@ public function getTypeFromFunctionCall(FunctionReflection $functionReflection,
 		if (count($functionCall->args) === 1) {
 			$argType = $scope->getType($functionCall->args[0]->value);
 			if ($argType->isArray()->yes()) {
+				$isIterable = $argType->isIterableAtLeastOnce();
+				if ($isIterable->no()) {
+					return new ConstantBooleanType(false);
+				}
 				$iterableValueType = $argType->getIterableValueType();
 				$argumentTypes = [];
+				if (!$isIterable->yes()) {
+					$argumentTypes[] = new ConstantBooleanType(false);
+				}
 				if ($iterableValueType instanceof UnionType) {
 					foreach ($iterableValueType->getTypes() as $innerType) {
 						$argumentTypes[] = $innerType;
diff --git a/tests/PHPStan/Analyser/NodeScopeResolverTest.php b/tests/PHPStan/Analyser/NodeScopeResolverTest.php
@@ -10009,6 +10009,11 @@ public function dataNativeMixedType(): array
 		return $this->gatherAssertTypes(__DIR__ . '/../Reflection/data/mixedType.php');
 	}
 
+	public function dataMinMaxReturnTypeWithArrays(): array
+	{
+		return $this->gatherAssertTypes(__DIR__ . '/data/minmax-arrays.php');
+	}
+
 	/**
 	 * @dataProvider dataBug2574
 	 * @dataProvider dataBug2577
@@ -10070,6 +10075,7 @@ public function dataNativeMixedType(): array
 	 * @dataProvider dataBitwiseNot
 	 * @dataProvider dataGraphicsDrawReturnTypes
 	 * @dataProvider dataNativeUnionTypes
+	 * @dataProvider dataMinMaxReturnTypeWithArrays
 	 * @param string $assertType
 	 * @param string $file
 	 * @param mixed ...$args
diff --git a/tests/PHPStan/Analyser/data/minmax-arrays.php b/tests/PHPStan/Analyser/data/minmax-arrays.php
@@ -0,0 +1,36 @@
+<?php
+
+namespace MinMaxArrays;
+
+use function PHPStan\Analyser\assertType;
+
+function dummy(): void
+{
+	assertType('1', min([1]));
+	assertType('false', min([]));
+	assertType('1', max([1]));
+	assertType('false', max([]));
+}
+
+/**
+ * @param int[] $ints
+ */
+function dummy2(array $ints): void
+{
+	if (count($ints) !== 0) {
+		assertType('int', min($ints));
+		assertType('int', max($ints));
+	} else {
+		assertType('false', min($ints));
+		assertType('false', max($ints));
+	}
+}
+
+/**
+ * @param int[] $ints
+ */
+function dummy3(array $ints): void
+{
+	assertType('int|false', min($ints));
+	assertType('int|false', max($ints));
+}
