Fix #8923

src/Psalm/Internal/Analyzer/ScopeAnalyzer.php

@@ -265,7 +265,8 @@ class ScopeAnalyzer
                     static fn(string $action): bool => $action !== self::ACTION_NONE
                 );
 
-                if ($stmt instanceof PhpParser\Node\Stmt\While_
+                if (($stmt instanceof PhpParser\Node\Stmt\While_
+                    || $stmt instanceof PhpParser\Node\Stmt\Do_)
                     && $nodes
                     && ($stmt_expr_type = $nodes->getType($stmt->cond))
                     && $stmt_expr_type->isAlwaysTruthy()

tests/Loop/DoTest.php

@@ -16,6 +16,14 @@ class DoTest extends TestCase
     public function providerValidCodeParse(): iterable
     {
         return [
+            'doWhileTrue' => [
+                'code' => '<?php
+                    function ret(): int {
+                        do {
+                            return 1;
+                        } while (true);
+                    }'
+            ],
             'doWhileVar' => [
                 'code' => '<?php
                     $worked = false;

tests/Loop/ForTest.php

@@ -16,6 +16,14 @@ class ForTest extends TestCase
     public function providerValidCodeParse(): iterable
     {
         return [
+            'forTrue' => [
+                'code' => '<?php
+                    function ret(): int {
+                        for (;;) {
+                            return 1;
+                        }
+                    }'
+            ],
             'implicitFourthLoop' => [
                 'code' => '<?php
                     function test(): int {

tests/Loop/WhileTest.php

@@ -14,6 +14,14 @@ class WhileTest extends TestCase
     public function providerValidCodeParse(): iterable
     {
         return [
+            'whileTrue' => [
+                'code' => '<?php
+                    function ret(): int {
+                        do {
+                            return 1;
+                        } while (true);
+                    }'
+            ],
             'whileVar' => [
                 'code' => '<?php
                     $worked = false;