Alter removes a reference variable, breaking the code after

[williamdes]

https://psalm.dev/r/7e011cd6cc

Source: https://github.com/phpmyadmin/phpmyadmin/blob/1835ebb4fccc20aa06868be88ab8bcaa9c395ccf/libraries/classes/Display/Results.php#L333

It removes the assignment ($relDb = &), but if you do that the code below will not work.

Same here:

diff --git a/libraries/classes/Plugins/Schema/Pdf/Pdf.php b/libraries/classes/Plugins/Schema/Pdf/Pdf.php
index 6e3dae46b2..90f956648e 100644
--- a/libraries/classes/Plugins/Schema/Pdf/Pdf.php
+++ b/libraries/classes/Plugins/Schema/Pdf/Pdf.php
@@ -398,7 +398,7 @@ class Pdf extends PdfLib
      */
     public function numLines($w, $txt)
     {
-        $cw = &$this->CurrentFont['cw'];
+        $this->CurrentFont['cw'];
         if ($w == 0) {
             $w = $this->w - $this->rMargin - $this->x;
         }

[psalm-github-bot]

I found these snippets:

https://psalm.dev/r/7e011cd6cc

<?php
class A {
    /** @var array */
    private $transformationInfo = [];
    
    function foo(): void {
        global $cfgRelation;
       
        $this->transformationInfo[$cfgRelation['db']] = [];
        $relDb = &$this->transformationInfo[$cfgRelation['db']];
            if (! empty($cfgRelation['history'])) {
                $relDb[$cfgRelation['history']] = ['sqlquery' => $sqlHighlightingData];
            }

            if (! empty($cfgRelation['bookmark'])) {
                $relDb[$cfgRelation['bookmark']] = ['query' => $sqlHighlightingData];
            }

    }
}

Psalm output (using commit c5190f0):

INFO: MixedArrayAccess - 9:35 - Cannot access array value on mixed variable $cfgRelation

INFO: MixedArrayOffset - 9:9 - Cannot access value on variable $this->transformationInfo[mixed] using mixed offset

INFO: MixedArrayAccess - 10:45 - Cannot access array value on mixed variable $cfgRelation

INFO: MixedArrayOffset - 10:19 - Cannot access value on variable $this->transformationInfo using mixed offset

INFO: MixedAssignment - 10:9 - Unable to determine the type that $relDb is being assigned to

ERROR: UndefinedVariable - 12:66 - Cannot find referenced variable $sqlHighlightingData

INFO: MixedArrayAccess - 12:24 - Cannot access array value on mixed variable $cfgRelation

INFO: MixedArrayAssignment - 12:17 - Cannot access array value on mixed variable $relDb[mixed]

INFO: MixedArrayOffset - 12:17 - Cannot access value on variable $relDb[mixed] using mixed offset

ERROR: UndefinedVariable - 16:64 - Cannot find referenced variable $sqlHighlightingData

INFO: MixedArrayAccess - 16:24 - Cannot access array value on mixed variable $cfgRelation

INFO: MixedArrayAssignment - 16:17 - Cannot access array value on mixed variable $relDb[mixed]

INFO: MixedArrayOffset - 16:17 - Cannot access value on variable $relDb[mixed] using mixed offset

INFO: UnusedVariable - 10:9 - $relDb is never referenced or the value is not used

[orklah]

Psalm already prevent emitting UnusedVariable on references. After #6129, it will also do that for globals. I think it'd also need to do it for variables that are references of others.

[AndrolGenhald]

I believe this is now fixed, likely by #7339. I tested by:

• Checking out that phpmyadmin commit
• composer update
• vendor/bin/psalm --alter --issues=UnusedVariable libraries/classes/Display/Results.php

And $relDb = & was removed, then:

• git checkout .
• composer require --dev vimeo/psalm="dev-master"
• Fix psalm.xml by removing totallyTyped="false"
• vendor/bin/psalm --alter --issues=UnusedVariable libraries/classes/Display/Results.php

And the line is not changed.