From 138cabd75aa923eff9f320675e905dafc2c3dc49 Mon Sep 17 00:00:00 2001
From: Ondrej Mirtes <ondrej@mirtes.cz>
Date: Wed, 11 Nov 2020 19:39:06 +0100
Subject: [PATCH] Support ARRAY_FILTER_USE_KEY and ARRAY_FILTER_USE_BOTH

---
 src/Analyser/NodeScopeResolver.php            | 25 ++++++++--
 .../Analyser/NodeScopeResolverTest.php        |  6 +++
 tests/PHPStan/Analyser/data/bug-3132.php      | 48 +++++++++++++++++++
 3 files changed, 76 insertions(+), 3 deletions(-)
 create mode 100644 tests/PHPStan/Analyser/data/bug-3132.php

diff --git a/src/Analyser/NodeScopeResolver.php b/src/Analyser/NodeScopeResolver.php
index 9f2e9fe0d9..55f9673fe2 100644
--- a/src/Analyser/NodeScopeResolver.php
+++ b/src/Analyser/NodeScopeResolver.php
@@ -2411,9 +2411,28 @@ private function processArgs(
 						&& $calleeReflection->getName() === 'array_filter'
 						&& isset($args[0])
 					) {
-						$parameterType = new CallableType([
-							new DummyParameter('item', $scope->getType($args[0]->value)->getIterableValueType(), false, PassedByReference::createNo(), false, null),
-						], new MixedType(), false);
+						if (isset($args[2])) {
+							$mode = $scope->getType($args[2]->value);
+							if ($mode instanceof ConstantIntegerType) {
+								if ($mode->getValue() === ARRAY_FILTER_USE_KEY) {
+									$arrayFilterParameters = [
+										new DummyParameter('key', $scope->getType($args[0]->value)->getIterableKeyType(), false, PassedByReference::createNo(), false, null),
+									];
+								} elseif ($mode->getValue() === ARRAY_FILTER_USE_BOTH) {
+									$arrayFilterParameters = [
+										new DummyParameter('item', $scope->getType($args[0]->value)->getIterableValueType(), false, PassedByReference::createNo(), false, null),
+										new DummyParameter('key', $scope->getType($args[0]->value)->getIterableKeyType(), false, PassedByReference::createNo(), false, null),
+									];
+								}
+							}
+						}
+						$parameterType = new CallableType(
+							$arrayFilterParameters ?? [
+								new DummyParameter('item', $scope->getType($args[0]->value)->getIterableValueType(), false, PassedByReference::createNo(), false, null),
+							],
+							new MixedType(),
+							false
+						);
 					}
 				}
 			}
diff --git a/tests/PHPStan/Analyser/NodeScopeResolverTest.php b/tests/PHPStan/Analyser/NodeScopeResolverTest.php
index 64fa2f38f1..2a0b0df629 100644
--- a/tests/PHPStan/Analyser/NodeScopeResolverTest.php
+++ b/tests/PHPStan/Analyser/NodeScopeResolverTest.php
@@ -10322,6 +10322,11 @@ public function dataBug2733(): array
 		return $this->gatherAssertTypes(__DIR__ . '/data/bug-2733.php');
 	}
 
+	public function dataBug3132(): array
+	{
+		return $this->gatherAssertTypes(__DIR__ . '/data/bug-3132.php');
+	}
+
 	/**
 	 * @param string $file
 	 * @return array<string, mixed[]>
@@ -10499,6 +10504,7 @@ private function gatherAssertTypes(string $file): array
 	 * @dataProvider dataCastToNumericString
 	 * @dataProvider dataBug2539
 	 * @dataProvider dataBug2733
+	 * @dataProvider dataBug3132
 	 * @param string $assertType
 	 * @param string $file
 	 * @param mixed ...$args
diff --git a/tests/PHPStan/Analyser/data/bug-3132.php b/tests/PHPStan/Analyser/data/bug-3132.php
new file mode 100644
index 0000000000..51e97e2afa
--- /dev/null
+++ b/tests/PHPStan/Analyser/data/bug-3132.php
@@ -0,0 +1,48 @@
+<?php
+
+namespace Bug3132;
+
+use function PHPStan\Analyser\assertType;
+use const ARRAY_FILTER_USE_BOTH;
+
+class Foo
+{
+
+	/**
+	 * @param array<string,object> $objects
+	 *
+	 * @return array<string,object>
+	 */
+	function filter(array $objects) : array
+	{
+		return array_filter($objects, static function ($key) {
+			assertType('string', $key);
+		}, ARRAY_FILTER_USE_KEY);
+	}
+
+	/**
+	 * @param array<string,object> $objects
+	 *
+	 * @return array<string,object>
+	 */
+	function bar(array $objects) : array
+	{
+		return array_filter($objects, static function ($val) {
+			assertType('object', $val);
+		});
+	}
+
+	/**
+	 * @param array<string,object> $objects
+	 *
+	 * @return array<string,object>
+	 */
+	function baz(array $objects) : array
+	{
+		return array_filter($objects, static function ($val, $key) {
+			assertType('string', $key);
+			assertType('object', $val);
+		}, ARRAY_FILTER_USE_BOTH);
+	}
+
+}