Make return type extension for array_column() aware of PHP version

src/Type/Php/ArrayColumnFunctionReturnTypeExtension.php

@@ -4,6 +4,7 @@
 
 use PhpParser\Node\Expr\FuncCall;
 use PHPStan\Analyser\Scope;
+use PHPStan\Php\PhpVersion;
 use PHPStan\Reflection\FunctionReflection;
 use PHPStan\Reflection\ParametersAcceptorSelector;
 use PHPStan\ShouldNotHappenException;
@@ -25,6 +26,10 @@
 class ArrayColumnFunctionReturnTypeExtension implements DynamicFunctionReturnTypeExtension
 {
 
+	public function __construct(private PhpVersion $phpVersion)
+	{
+	}
+
 	public function isFunctionSupported(FunctionReflection $functionReflection): bool
 	{
 		return $functionReflection->getName() === 'array_column';
@@ -187,15 +192,17 @@ private function castToArrayKeyType(Type $type): Type
 	{
 		$isArray = $type->isArray();
 		if ($isArray->yes()) {
-			return new IntegerType();
+			return $this->phpVersion->throwsTypeErrorForInternalFunctions() ? new NeverType() : new IntegerType();
 		}
 		if ($isArray->no()) {
 			return ArrayType::castToArrayKeyType($type);
 		}
-		return TypeCombinator::union(
-			ArrayType::castToArrayKeyType(TypeCombinator::remove($type, new ArrayType(new MixedType(), new MixedType()))),
-			new IntegerType(),
-		);
+		$withoutArrayType = TypeCombinator::remove($type, new ArrayType(new MixedType(), new MixedType()));
+		$keyType = ArrayType::castToArrayKeyType($withoutArrayType);
+		if ($this->phpVersion->throwsTypeErrorForInternalFunctions()) {
+			return $keyType;
+		}
+		return TypeCombinator::union($keyType, new IntegerType());
 	}
 
 }

tests/PHPStan/Analyser/NodeScopeResolverTest.php

@@ -666,7 +666,14 @@ public function dataFileAsserts(): iterable
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-6399.php');
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-4357.php');
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-5817.php');
+
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/array-column.php');
+		if (PHP_VERSION_ID >= 80000) {
+			yield from $this->gatherAssertTypes(__DIR__ . '/data/array-column-php8.php');
+		} else {
+			yield from $this->gatherAssertTypes(__DIR__ . '/data/array-column-php7.php');
+		}
+
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-6497.php');
 
 		if (PHP_VERSION_ID >= 70400) {

tests/PHPStan/Analyser/data/array-column-php7.php

@@ -0,0 +1,22 @@
+<?php
+
+namespace ArrayColumn\Php7;
+
+use function PHPStan\Testing\assertType;
+
+class ArrayColumnPhp7Test
+{
+
+	/** @param array<int, array{column: string, key: array}> $array */
+	public function testConstantArray1(array $array): void
+	{
+		assertType('array<int, string>', array_column($array, 'column', 'key'));
+	}
+
+	/** @param array<int, array{column: string, key: array|string}> $array */
+	public function testConstantArray2(array $array): void
+	{
+		assertType('array<int|string, string>', array_column($array, 'column', 'key'));
+	}
+
+}

tests/PHPStan/Analyser/data/array-column-php8.php

@@ -0,0 +1,22 @@
+<?php
+
+namespace ArrayColumn\Php8;
+
+use function PHPStan\Testing\assertType;
+
+class ArrayColumnPhp7Test
+{
+
+	/** @param array<int, array{column: string, key: array}> $array */
+	public function testConstantArray1(array $array): void
+	{
+		assertType('array<*NEVER*, string>', array_column($array, 'column', 'key'));
+	}
+
+	/** @param array<int, array{column: string, key: array|string}> $array */
+	public function testConstantArray2(array $array): void
+	{
+		assertType('array<string, string>', array_column($array, 'column', 'key'));
+	}
+
+}