From b3150d451aa6356cfab43704cd7f5fe4e285025b Mon Sep 17 00:00:00 2001
From: Bruce Weirdan <weirdan@gmail.com>
Date: Mon, 28 Aug 2023 01:58:02 +0200
Subject: [PATCH] Fix crash on property access to undefined property on a class
 with a missing dependncy

---
 src/Psalm/Storage/ClassLikeStorage.php        |  4 ++++
 .../Fetch/AtomicPropertyFetchAnalyzerTest.php | 19 +++++++++++++++++++
 2 files changed, 23 insertions(+)

diff --git a/src/Psalm/Storage/ClassLikeStorage.php b/src/Psalm/Storage/ClassLikeStorage.php
index 5be0d5221..f8564444a 100644
--- a/src/Psalm/Storage/ClassLikeStorage.php
+++ b/src/Psalm/Storage/ClassLikeStorage.php
@@ -501,6 +501,10 @@ final class ClassLikeStorage implements HasAttributesInterface
         }
 
         foreach ($this->parent_classes as $parent_class) {
+            // skip missing dependencies
+            if (!$codebase->classlike_storage_provider->has($parent_class)) {
+                continue;
+            }
             $parent_class_storage = $codebase->classlike_storage_provider->get($parent_class);
             if ($parent_class_storage->hasAttribute($fq_class_name)) {
                 return true;
diff --git a/tests/Internal/Analyzer/Statements/Expression/Fetch/AtomicPropertyFetchAnalyzerTest.php b/tests/Internal/Analyzer/Statements/Expression/Fetch/AtomicPropertyFetchAnalyzerTest.php
index 250f52dae..e34a9ab87 100644
--- a/tests/Internal/Analyzer/Statements/Expression/Fetch/AtomicPropertyFetchAnalyzerTest.php
+++ b/tests/Internal/Analyzer/Statements/Expression/Fetch/AtomicPropertyFetchAnalyzerTest.php
@@ -5,11 +5,13 @@ declare(strict_types=1);
 namespace Psalm\Tests\Internal\Analyzer\Statements\Expression\Fetch;
 
 use Psalm\Tests\TestCase;
+use Psalm\Tests\Traits\InvalidCodeAnalysisTestTrait;
 use Psalm\Tests\Traits\ValidCodeAnalysisTestTrait;
 
 final class AtomicPropertyFetchAnalyzerTest extends TestCase
 {
     use ValidCodeAnalysisTestTrait;
+    use InvalidCodeAnalysisTestTrait;
 
     public function providerValidCodeParse(): iterable
     {
@@ -72,4 +74,21 @@ final class AtomicPropertyFetchAnalyzerTest extends TestCase
             ],
         ];
     }
+
+    public function providerInvalidCodeParse(): iterable
+    {
+        return [
+            'undefinedPropertyAccessOnMissingDependency' => [
+                'code' => <<<'PHP'
+                    <?php
+                    class A extends Missing {}
+                    function make(): A { return new A; }
+
+                    make()->prop;
+                    PHP,
+                'error_message' => 'UndefinedPropertyFetch',
+                'ignored_issues' => ['MissingDependency'],
+            ],
+        ];
+    }
 }