From bde9ba0af015b9500107c3792e940a42466f3daf Mon Sep 17 00:00:00 2001
From: staabm <120441+staabm@users.noreply.github.com>
Date: Sun, 1 Mar 2026 11:41:48 +0000
Subject: [PATCH] Fix slow analysis on large coalesce chains

- Avoided expensive $scope->getType($expr->right) call when the right
  side of a coalesce is itself a Coalesce expression
- For right-associative chains like $a ?? $b ?? $c ?? $d, getType on
  the nested chain recursively evaluated the entire remaining chain
  at each level, causing O(N^2) complexity
- Since a nested Coalesce expression is never an explicit NeverType,
  the getType call can be safely skipped for Coalesce right operands
- New regression test in tests/PHPStan/Analyser/data/bug-14214.php

Closes https://github.com/phpstan/phpstan/issues/14214
---
 src/Analyser/NodeScopeResolver.php            |  2 +-
 .../Analyser/AnalyserIntegrationTest.php      |  6 ++
 tests/PHPStan/Analyser/data/bug-14214.php     | 88 +++++++++++++++++++
 3 files changed, 95 insertions(+), 1 deletion(-)
 create mode 100644 tests/PHPStan/Analyser/data/bug-14214.php

diff --git a/src/Analyser/NodeScopeResolver.php b/src/Analyser/NodeScopeResolver.php
index d5f62a9b8a7..dd0641824c1 100644
--- a/src/Analyser/NodeScopeResolver.php
+++ b/src/Analyser/NodeScopeResolver.php
@@ -3692,7 +3692,7 @@ function (MutatingScope $scope) use ($stmt, $expr, $nodeCallback, $context, $sto
 
 			$rightScope = $scope->filterByFalseyValue($expr);
 			$rightResult = $this->processExprNode($stmt, $expr->right, $rightScope, $storage, $nodeCallback, $context->enterDeep());
-			$rightExprType = $scope->getType($expr->right);
+			$rightExprType = $expr->right instanceof Coalesce ? null : $scope->getType($expr->right);
 			if ($rightExprType instanceof NeverType && $rightExprType->isExplicit()) {
 				$scope = $scope->filterByTruthyValue(new Expr\Isset_([$expr->left]));
 			} else {
diff --git a/tests/PHPStan/Analyser/AnalyserIntegrationTest.php b/tests/PHPStan/Analyser/AnalyserIntegrationTest.php
index 820338325d9..7d17f188a2e 100644
--- a/tests/PHPStan/Analyser/AnalyserIntegrationTest.php
+++ b/tests/PHPStan/Analyser/AnalyserIntegrationTest.php
@@ -1644,6 +1644,12 @@ public function testBug14207And(): void
 		$this->assertNoErrors($errors);
 	}
 
+	public function testBug14214(): void
+	{
+		$errors = $this->runAnalyse(__DIR__ . '/data/bug-14214.php');
+		$this->assertNoErrors($errors);
+	}
+
 	public function testBug13945(): void
 	{
 		$errors = $this->runAnalyse(__DIR__ . '/data/bug-13945.php');
diff --git a/tests/PHPStan/Analyser/data/bug-14214.php b/tests/PHPStan/Analyser/data/bug-14214.php
new file mode 100644
index 00000000000..2539d106d84
--- /dev/null
+++ b/tests/PHPStan/Analyser/data/bug-14214.php
@@ -0,0 +1,88 @@
+<?php declare(strict_types = 1);
+
+namespace Bug14214;
+
+use function PHPStan\Testing\assertType;
+
+class HelloWorld
+{
+	public static function is_too_slow(): void
+	{
+		$x0 = $x1 = $x2 = $x3 = $x4 = $x5 = $x6 = $x7 = $x8 = $x9 = $x10 = null;
+		$x11 = $x12 = $x13 = $x14 = $x15 = $x16 = null;
+
+		if (rand(0, 1)) {
+			$x0 = rand(0, 1);
+		}
+		if (rand(0, 1)) {
+			$x1 = rand(2, 3);
+		}
+		if (rand(0, 1)) {
+			$x2 = rand(4, 5);
+		}
+		if (rand(0, 1)) {
+			$x3 = rand(6, 7);
+		}
+		if (rand(0, 1)) {
+			$x4 = rand(8, 9);
+		}
+		if (rand(0, 1)) {
+			$x5 = rand(10, 11);
+		}
+		if (rand(0, 1)) {
+			$x6 = rand(12, 13);
+		}
+		if (rand(0, 1)) {
+			$x7 = rand(14, 15);
+		}
+		if (rand(0, 1)) {
+			$x8 = rand(16, 17);
+		}
+		if (rand(0, 1)) {
+			$x9 = rand(18, 19);
+		}
+		if (rand(0, 1)) {
+			$x10 = rand(20, 21);
+		}
+		if (rand(0, 1)) {
+			$x11 = rand(22, 23);
+		}
+		if (rand(0, 1)) {
+			$x12 = rand(24, 25);
+		}
+		if (rand(0, 1)) {
+			$x13 = rand(26, 27);
+		}
+		if (rand(0, 1)) {
+			$x14 = rand(28, 29);
+		}
+		if (rand(0, 1)) {
+			$x15 = rand(30, 31);
+		}
+		if (rand(0, 1)) {
+			$x16 = rand(32, 33);
+		}
+
+		$x = (
+			$x0 ??
+			$x1 ??
+			$x2 ??
+			$x3 ??
+			$x4 ??
+			$x5 ??
+			$x6 ??
+			$x7 ??
+			$x8 ??
+			$x9 ??
+			$x10 ??
+			$x11 ??
+			$x12 ??
+			$x13 ??
+			$x14 ??
+			$x15 ??
+			$x16
+		);
+
+		assertType('int<0, 33>|null', $x);
+	}
+}