array_push preserves list

Author: ondrejmirtes

src/Analyser/NodeScopeResolver.php

@@ -3145,9 +3145,13 @@ static function (?Type $offsetType, Type $valueType, bool $optional) use (&$arra
 
 				if ($constantArray->isConstantArray()->yes() && $nonConstantArrayWasUnpacked) {
 					$array = new ArrayType($constantArray->generalize(GeneralizePrecision::lessSpecific())->getIterableKeyType(), $constantArray->getIterableValueType());
+					$isList = $constantArray->isList()->yes();
 					$constantArray = $constantArray->isIterableAtLeastOnce()->yes()
 						? TypeCombinator::intersect($array, new NonEmptyArrayType())
 						: $array;
+					$constantArray = $isList
+						? AccessoryArrayListType::intersectWith($constantArray)
+						: $constantArray;
 				}
 
 				$newArrayTypes[] = $constantArray;

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

@@ -66,7 +66,7 @@ function arrayPushConstantArray(): void
 	/** @var array<bool|null> $f1 */
 	$f1 = [];
 	array_push($f, ...$f1);
-	assertType('non-empty-array<int<0, max>, 17|bool|null>', $f);
+	assertType('non-empty-list<17|bool|null>', $f);
 
 	$g = [new stdClass()];
 	array_push($g, ...[new stdClass(), new stdClass()]);

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

@@ -66,7 +66,7 @@ function arrayUnshiftConstantArray(): void
 	/** @var array<bool|null> $f1 */
 	$f1 = [];
 	array_unshift($f, ...$f1);
-	assertType('non-empty-array<int<0, max>, 17|bool|null>', $f);
+	assertType('non-empty-list<17|bool|null>', $f);
 
 	$g = [new stdClass()];
 	array_unshift($g, ...[new stdClass(), new stdClass()]);

tests/PHPStan/Analyser/data/bug-7115.php

@@ -27,7 +27,7 @@ public function doFoo(): void
 			array_push($d, $thing);
 		}
 
-		assertType('array<int<0, max>, array{a: int, b: string}>', $b);
+		assertType('list<array{a: int, b: string}>', $b);
 		assertType('list<array{a: int, b: string}>', $c);
 		assertType('list<array{a: int, b: string}>', $d);
 	}

tests/PHPStan/Rules/Methods/ReturnTypeRuleTest.php

@@ -998,4 +998,9 @@ public function testBug5008(): void
 		$this->analyse([__DIR__ . '/data/bug-5008.php'], []);
 	}
 
+	public function testArrayPushPreservesList(): void
+	{
+		$this->analyse([__DIR__ . '/data/array-push-preserves-list.php'], []);
+	}
+
 }

tests/PHPStan/Rules/Methods/data/array-push-preserves-list.php

@@ -0,0 +1,83 @@
+<?php
+
+namespace ArrayPushPreservesList;
+
+use function array_unshift;
+
+class Foo
+{
+
+	/**
+	 * @param list<int> $a
+	 * @return list<int>
+	 */
+	public function doFoo(array $a): array
+	{
+		array_push($a, ...$a);
+
+		return $a;
+	}
+
+	/**
+	 * @param list<int> $a
+	 * @return list<int>
+	 */
+	public function doFoo2(array $a): array
+	{
+		array_push($a, ...[1, 2, 3]);
+
+		return $a;
+	}
+
+	/**
+	 * @param list<int> $a
+	 * @return list<int>
+	 */
+	public function doFoo3(array $a): array
+	{
+		$b = [1, 2, 3];
+		array_push($b, ...$a);
+
+		return $b;
+	}
+
+}
+
+class Bar
+{
+
+	/**
+	 * @param list<int> $a
+	 * @return list<int>
+	 */
+	public function doFoo(array $a): array
+	{
+		array_unshift($a, ...$a);
+
+		return $a;
+	}
+
+	/**
+	 * @param list<int> $a
+	 * @return list<int>
+	 */
+	public function doFoo2(array $a): array
+	{
+		array_unshift($a, ...[1, 2, 3]);
+
+		return $a;
+	}
+
+	/**
+	 * @param list<int> $a
+	 * @return list<int>
+	 */
+	public function doFoo3(array $a): array
+	{
+		$b = [1, 2, 3];
+		array_unshift($b, ...$a);
+
+		return $b;
+	}
+
+}