From 1514837104b12d4a95c8ed389ed9fee01cf50c9b Mon Sep 17 00:00:00 2001
From: Ardit Tirana <ardit.tirana@protonmail.com>
Date: Mon, 22 Jun 2026 15:41:46 +0200
Subject: [PATCH] Avoid using a null alias as an array offset in getAliases()

Misc::getAliases() built a table-alias map with
`$tables[$thisDb][$expr->alias] = $expr->table` for every FROM/JOIN
expression. When a table has no alias, `$expr->alias` is null, so this
used null as an array offset, which is deprecated as of PHP 8.5. The
null-keyed entry was never read back: the only consumer looks up
`$tables[$thisDb][$expr->table]`, whose offset is always a non-empty
string.

Skip expressions without an alias. getAliases() output is unchanged.
Removes the now-resolved PossiblyNullArrayOffset baseline entry and adds
a regression test.
---
 psalm-baseline.xml       |  3 ---
 src/Utils/Misc.php       |  4 ++++
 tests/Utils/MiscTest.php | 19 +++++++++++++++++++
 3 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/psalm-baseline.xml b/psalm-baseline.xml
index 50327a724..10ebc58ed 100644
--- a/psalm-baseline.xml
+++ b/psalm-baseline.xml
@@ -1359,9 +1359,6 @@
     <MixedArrayOffset occurrences="1">
       <code>$tables[$thisDb][$expr-&gt;table]</code>
     </MixedArrayOffset>
-    <PossiblyNullArrayOffset occurrences="1">
-      <code>$tables[$thisDb]</code>
-    </PossiblyNullArrayOffset>
   </file>
   <file src="src/Utils/Query.php">
     <InvalidNullableReturnType occurrences="1">
diff --git a/src/Utils/Misc.php b/src/Utils/Misc.php
index f4e0bcd83..97a9ca816 100644
--- a/src/Utils/Misc.php
+++ b/src/Utils/Misc.php
@@ -68,6 +68,10 @@ public static function getAliases($statement, $database)
                 ];
             }
 
+            if (null === $expr->alias || $expr->alias === '') {
+                continue;
+            }
+
             if (! isset($tables[$thisDb])) {
                 $tables[$thisDb] = [];
             }
diff --git a/tests/Utils/MiscTest.php b/tests/Utils/MiscTest.php
index 192b22c34..6c775ccbf 100644
--- a/tests/Utils/MiscTest.php
+++ b/tests/Utils/MiscTest.php
@@ -132,6 +132,25 @@ public static function getAliasesProvider(): array
                     ],
                 ],
             ],
+            [
+                'SELECT mytable.a x, o.b y FROM mytable JOIN other o ON o.id = mytable.id',
+                'shop',
+                [
+                    'shop' => [
+                        'alias' => null,
+                        'tables' => [
+                            'mytable' => [
+                                'alias' => null,
+                                'columns' => ['a' => 'x'],
+                            ],
+                            'other' => [
+                                'alias' => 'o',
+                                'columns' => ['b' => 'y'],
+                            ],
+                        ],
+                    ],
+                ],
+            ],
         ];
     }
 }