From 7e359b13018bb1eabbfc10c1ab66d37e10826fe7 Mon Sep 17 00:00:00 2001
From: Sam Anglin <sam@mizouzie.dev>
Date: Tue, 7 Apr 2026 13:57:58 +0300
Subject: [PATCH 1/3] Fix infinite recursion in ConstantArrayType::isCallable()
 via RecursionGuard

---
 src/Type/Constant/ConstantArrayType.php       | 34 ++++++++++++-------
 .../Analyser/AnalyserIntegrationTest.php      |  8 +++++
 .../bug-constant-array-callable-recursion.php | 22 ++++++++++++
 3 files changed, 52 insertions(+), 12 deletions(-)
 create mode 100644 tests/PHPStan/Analyser/data/bug-constant-array-callable-recursion.php

diff --git a/src/Type/Constant/ConstantArrayType.php b/src/Type/Constant/ConstantArrayType.php
index aa711029a8d..32c5daa583c 100644
--- a/src/Type/Constant/ConstantArrayType.php
+++ b/src/Type/Constant/ConstantArrayType.php
@@ -42,6 +42,7 @@
 use PHPStan\Type\MixedType;
 use PHPStan\Type\NeverType;
 use PHPStan\Type\NullType;
+use PHPStan\Type\RecursionGuard;
 use PHPStan\Type\Traits\ArrayTypeTrait;
 use PHPStan\Type\Traits\NonObjectTypeTrait;
 use PHPStan\Type\Traits\UndecidedComparisonTypeTrait;
@@ -494,23 +495,32 @@ public function equals(Type $type): bool
 
 	public function isCallable(): TrinaryLogic
 	{
-		$hasNonExistentMethod = false;
-		$typeAndMethods = $this->doFindTypeAndMethodNames($hasNonExistentMethod);
-		if ($typeAndMethods === []) {
-			return TrinaryLogic::createNo();
-		}
+		$result = RecursionGuard::run($this, function (): TrinaryLogic {
+			$hasNonExistentMethod = false;
+			$typeAndMethods = $this->doFindTypeAndMethodNames($hasNonExistentMethod);
+			if ($typeAndMethods === []) {
+				return TrinaryLogic::createNo();
+			}
 
-		$results = array_map(
-			static fn (ConstantArrayTypeAndMethod $typeAndMethod): TrinaryLogic => $typeAndMethod->getCertainty(),
-			$typeAndMethods,
-		);
+			$results = array_map(
+				static fn (ConstantArrayTypeAndMethod $typeAndMethod): TrinaryLogic => $typeAndMethod->getCertainty(),
+				$typeAndMethods,
+			);
 
-		$result = TrinaryLogic::createYes()->and(...$results);
+			$result = TrinaryLogic::createYes()->and(...$results);
 
-		if ($hasNonExistentMethod) {
-			$result = $result->and(TrinaryLogic::createMaybe());
+			if ($hasNonExistentMethod) {
+				$result = $result->and(TrinaryLogic::createMaybe());
+			}
+
+			return $result;
+		});
+
+		if ($result instanceof ErrorType) {
+			return TrinaryLogic::createNo();
 		}
 
+
 		return $result;
 	}
 
diff --git a/tests/PHPStan/Analyser/AnalyserIntegrationTest.php b/tests/PHPStan/Analyser/AnalyserIntegrationTest.php
index 9020c4b3c4a..6cb682edbcc 100644
--- a/tests/PHPStan/Analyser/AnalyserIntegrationTest.php
+++ b/tests/PHPStan/Analyser/AnalyserIntegrationTest.php
@@ -93,6 +93,14 @@ public function testInfiniteRecursionWithCallable(): void
 		$this->assertNoErrors($errors);
 	}
 
+	public function testConstantArrayCallableDoesNotCauseInfiniteRecursion(): void
+	{
+		// Previously caused infinite recursion / OOM via ConstantArrayType::isCallable()
+		// resolving getMethod() which triggered return type resolution that called isCallable() again
+		$errors = $this->runAnalyse(__DIR__ . '/data/bug-constant-array-callable-recursion.php');
+		$this->assertCount(3, $errors);
+	}
+
 	public function testClassThatExtendsUnknownClassIn3rdPartyPropertyTypeShouldNotCauseAutoloading(): void
 	{
 		// no error about PHPStan\Tests\Baz not being able to be autoloaded
diff --git a/tests/PHPStan/Analyser/data/bug-constant-array-callable-recursion.php b/tests/PHPStan/Analyser/data/bug-constant-array-callable-recursion.php
new file mode 100644
index 00000000000..db244a276f7
--- /dev/null
+++ b/tests/PHPStan/Analyser/data/bug-constant-array-callable-recursion.php
@@ -0,0 +1,22 @@
+<?php
+
+namespace BugConstantArrayCallableRecursion;
+
+class Period
+{
+
+	/**
+	 * @return array{'BugConstantArrayCallableRecursion\Period', 'endIteration'}
+	 */
+	public function endIteration(): callable
+	{
+		return [self::class, 'endIteration'];
+	}
+
+}
+
+function test(): void
+{
+	$cb = ['BugConstantArrayCallableRecursion\Period', 'endIteration'];
+	is_callable($cb);
+}

From c7842c6e4663c13217638be34c218fddb60c32ea Mon Sep 17 00:00:00 2001
From: Sam Anglin <sam@mizouzie.dev>
Date: Tue, 7 Apr 2026 16:44:28 +0300
Subject: [PATCH 2/3] Address coding standards

---
 src/Type/Constant/ConstantArrayType.php | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/Type/Constant/ConstantArrayType.php b/src/Type/Constant/ConstantArrayType.php
index 32c5daa583c..c5cf80b83c0 100644
--- a/src/Type/Constant/ConstantArrayType.php
+++ b/src/Type/Constant/ConstantArrayType.php
@@ -520,7 +520,6 @@ public function isCallable(): TrinaryLogic
 			return TrinaryLogic::createNo();
 		}
 
-
 		return $result;
 	}
 

From 206c197498f1fbadd22ff2cf12ae462971e236b5 Mon Sep 17 00:00:00 2001
From: Sam <90829439+MizouziE@users.noreply.github.com>
Date: Tue, 7 Apr 2026 17:14:17 +0300
Subject: [PATCH 3/3] Update tests/PHPStan/Analyser/AnalyserIntegrationTest.php

Co-authored-by: Markus Staab <maggus.staab@googlemail.com>
---
 tests/PHPStan/Analyser/AnalyserIntegrationTest.php | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tests/PHPStan/Analyser/AnalyserIntegrationTest.php b/tests/PHPStan/Analyser/AnalyserIntegrationTest.php
index 6cb682edbcc..0288da8ba15 100644
--- a/tests/PHPStan/Analyser/AnalyserIntegrationTest.php
+++ b/tests/PHPStan/Analyser/AnalyserIntegrationTest.php
@@ -93,6 +93,7 @@ public function testInfiniteRecursionWithCallable(): void
 		$this->assertNoErrors($errors);
 	}
 
+	#[RequiresPhp('>= 8.0')]
 	public function testConstantArrayCallableDoesNotCauseInfiniteRecursion(): void
 	{
 		// Previously caused infinite recursion / OOM via ConstantArrayType::isCallable()