Array after array_push / array_unshift call can still be empty

Author: herndlm

src/Analyser/NodeScopeResolver.php

@@ -1825,7 +1825,7 @@ function (MutatingScope $scope) use ($expr, $nodeCallback, $context): Expression
 
 				/**
 				 * @param Arg[] $callArgs
-				 * @param callable(?Type, Type, bool=): void $setOffsetValueType
+				 * @param callable(?Type, Type, bool): void $setOffsetValueType
 				 */
 				$setOffsetValueTypes = static function (Scope $scope, array $callArgs, callable $setOffsetValueType, ?bool &$nonConstantArrayWasUnpacked = null): void {
 					foreach ($callArgs as $callArg) {
@@ -1850,7 +1850,7 @@ function (MutatingScope $scope) use ($expr, $nodeCallback, $context): Expression
 							}
 							continue;
 						}
-						$setOffsetValueType(null, $callArgType);
+						$setOffsetValueType(null, $callArgType, false);
 					}
 				};
 
@@ -1861,7 +1861,7 @@ function (MutatingScope $scope) use ($expr, $nodeCallback, $context): Expression
 					$setOffsetValueTypes(
 						$scope,
 						$callArgs,
-						static function (?Type $offsetType, Type $valueType, bool $optional = false) use (&$arrayTypeBuilder): void {
+						static function (?Type $offsetType, Type $valueType, bool $optional) use (&$arrayTypeBuilder): void {
 							$arrayTypeBuilder->setOffsetValueType($offsetType, $valueType, $optional);
 						},
 						$nonConstantArrayWasUnpacked,
@@ -1890,8 +1890,14 @@ static function (?Type $offsetType, Type $valueType, bool $optional = false) use
 					$setOffsetValueTypes(
 						$scope,
 						$callArgs,
-						static function (?Type $offsetType, Type $valueType) use (&$arrayType): void {
+						static function (?Type $offsetType, Type $valueType, bool $optional) use (&$arrayType): void {
+							$isIterableAtLeastOnce = $arrayType->isIterableAtLeastOnce()->yes() || !$optional;
 							$arrayType = $arrayType->setOffsetValueType($offsetType, $valueType);
+							if ($isIterableAtLeastOnce) {
+								return;
+							}
+
+							$arrayType = TypeCombinator::union(...TypeUtils::getArrays($arrayType));
 						},
 					);
 				}

tests/PHPStan/Analyser/data/array-push.php

@@ -13,10 +13,14 @@
  * @param non-empty-array<int> $c
  * @param array<int|string> $d
  */
-function arrayPush(array $a, array $b, array $c, array $d): void
+function arrayPush(array $a, array $b, array $c, array $d, array $arr): void
 {
 	array_push($a, ...$b);
-	assertType('non-empty-array<int|string>', $a);
+	assertType('array<int|string>', $a);
+
+	/** @var non-empty-array<string> $arr */
+	array_push($arr, ...$b);
+	assertType('non-empty-array<int|string>', $arr);
 
 	array_push($b, ...[]);
 	assertType('array<int>', $b);
@@ -27,7 +31,7 @@ function arrayPush(array $a, array $b, array $c, array $d): void
 	/** @var array<bool|null> $d1 */
 	$d1 = [];
 	array_push($d, ...$d1);
-	assertType('non-empty-array<bool|int|string|null>', $d);
+	assertType('array<bool|int|string|null>', $d);
 }
 
 function arrayPushConstantArray(): void

tests/PHPStan/Analyser/data/array-unshift.php

@@ -13,10 +13,14 @@
  * @param non-empty-array<int> $c
  * @param array<int|string> $d
  */
-function arrayUnshift(array $a, array $b, array $c, array $d): void
+function arrayUnshift(array $a, array $b, array $c, array $d, array $arr): void
 {
 	array_unshift($a, ...$b);
-	assertType('non-empty-array<int|string>', $a);
+	assertType('array<int|string>', $a);
+
+	/** @var non-empty-array<string> $arr */
+	array_unshift($arr, ...$b);
+	assertType('non-empty-array<int|string>', $arr);
 
 	array_unshift($b, ...[]);
 	assertType('array<int>', $b);
@@ -27,7 +31,7 @@ function arrayUnshift(array $a, array $b, array $c, array $d): void
 	/** @var array<bool|null> $d1 */
 	$d1 = [];
 	array_unshift($d, ...$d1);
-	assertType('non-empty-array<bool|int|string|null>', $d);
+	assertType('array<bool|int|string|null>', $d);
 }
 
 function arrayUnshiftConstantArray(): void

tests/PHPStan/Rules/Variables/EmptyRuleTest.php

@@ -169,4 +169,12 @@ public function testBug7318(): void
 		$this->analyse([__DIR__ . '/../Properties/data/bug-7318.php'], []);
 	}
 
+	public function testBug7424(): void
+	{
+		$this->treatPhpDocTypesAsCertain = true;
+		$this->strictUnnecessaryNullsafePropertyFetch = false;
+
+		$this->analyse([__DIR__ . '/data/bug-7424.php'], []);
+	}
+
 }

tests/PHPStan/Rules/Variables/data/bug-7424.php

@@ -0,0 +1,35 @@
+<?php
+
+namespace Bug7424;
+
+class Test
+{
+	public function run(): void
+	{
+		$data = $this->getInitData();
+
+		array_push($data, ...$this->getExtra());
+
+		if (empty($data)) {
+			return;
+		}
+
+		echo 'Proceeding to process data';
+	}
+
+	/**
+	 * @return string[]
+	 */
+	protected function getInitData(): array
+	{
+		return [];
+	}
+
+	/**
+	 * @return string[]
+	 */
+	protected function getExtra(): array
+	{
+		return [];
+	}
+}