Make NonEmptyArrayType::toArray() return $this

Author: zonuexe

src/Type/Accessory/NonEmptyArrayType.php

@@ -406,7 +406,7 @@ public function toString(): Type
 
 	public function toArray(): Type
 	{
-		return new MixedType();
+		return $this;
 	}
 
 	public function toArrayKey(): Type

src/Type/Php/ArraySliceFunctionReturnTypeExtension.php

@@ -5,6 +5,7 @@
 use PhpParser\Node\Expr\FuncCall;
 use PHPStan\Analyser\Scope;
 use PHPStan\Reflection\FunctionReflection;
+use PHPStan\Type\Constant\ConstantArrayType;
 use PHPStan\Type\Constant\ConstantIntegerType;
 use PHPStan\Type\DynamicFunctionReturnTypeExtension;
 use PHPStan\Type\Type;
@@ -50,7 +51,7 @@ public function getTypeFromFunctionCall(FunctionReflection $functionReflection,
 		}
 
 		if ($valueType->isIterableAtLeastOnce()->yes()) {
-			return $valueType->toArray();
+			return TypeCombinator::union($valueType, new ConstantArrayType([], []));
 		}
 
 		return $valueType;

tests/PHPStan/Analyser/NodeScopeResolverTest.php

@@ -1260,6 +1260,7 @@ public function dataFileAsserts(): iterable
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/base64_decode.php');
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-9404.php');
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/globals.php');
+		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-9208.php');
 	}
 
 	/**

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

@@ -9,10 +9,14 @@ class Foo
 
 	/**
 	 * @param non-empty-array $a
+	 * @param non-empty-list $b
+	 * @param non-empty-array<int>|non-empty-list<string> $c
 	 */
-	public function nonEmpty(array $a): void
+	public function nonEmpty(array $a, array $b, array $c): void
 	{
 		assertType('array', array_slice($a, 1));
+		assertType('list<mixed>', array_slice($b, 1));
+		assertType('array<int|string>', array_slice($c, 1));
 	}
 
 	/**

tests/PHPStan/Analyser/data/bug-9208.php

@@ -0,0 +1,22 @@
+<?php
+
+namespace Bug9208;
+
+use function PHPStan\Testing\assertType;
+
+/**
+ * @param int|non-empty-list<int> $id_or_ids
+ * @return non-empty-list<int>
+ */
+function f(int|array $id_or_ids): array
+{
+	if (is_array($id_or_ids)) {
+		assertType('non-empty-list<int>', (array)$id_or_ids);
+	} else {
+		assertType('array{int}', (array)$id_or_ids);
+	}
+
+	$ids = (array)$id_or_ids;
+	assertType('non-empty-list<int>', $ids);
+	return $ids;
+}