From 3f52ded9c37a9ab227b8052e132223efd97acc44 Mon Sep 17 00:00:00 2001
From: Bruce Weirdan <weirdan@gmail.com>
Date: Fri, 24 Feb 2023 00:53:36 -0400
Subject: [PATCH] Correctly process use aliases in `@psalm-scope-this`

Fixes vimeo/psalm#9386
---
 .../Internal/Analyzer/StatementsAnalyzer.php      | 15 +++++++--------
 tests/TypeReconciliation/ScopeTest.php            | 15 +++++++++++++++
 2 files changed, 22 insertions(+), 8 deletions(-)

diff --git a/src/Psalm/Internal/Analyzer/StatementsAnalyzer.php b/src/Psalm/Internal/Analyzer/StatementsAnalyzer.php
index c13850f0a98..896f5ac3878 100644
--- a/src/Psalm/Internal/Analyzer/StatementsAnalyzer.php
+++ b/src/Psalm/Internal/Analyzer/StatementsAnalyzer.php
@@ -76,7 +76,6 @@
 use function get_class;
 use function in_array;
 use function is_string;
-use function ltrim;
 use function preg_split;
 use function reset;
 use function round;
@@ -794,21 +793,21 @@ private function parseStatementDocblock(
 
         if (isset($comments->tags['psalm-scope-this'])) {
             $trimmed = trim(reset($comments->tags['psalm-scope-this']));
-            $trimmed = ltrim($trimmed, '\\');
+            $scope_fqcn = Type::getFQCLNFromString($trimmed, $this->getAliases());
 
-            if (!$codebase->classExists($trimmed)) {
+            if (!$codebase->classExists($scope_fqcn)) {
                 IssueBuffer::maybeAdd(
                     new UndefinedDocblockClass(
-                        'Scope class ' . $trimmed . ' does not exist',
+                        'Scope class ' . $scope_fqcn . ' does not exist',
                         new CodeLocation($this->getSource(), $stmt, null, true),
-                        $trimmed,
+                        $scope_fqcn,
                     ),
                 );
             } else {
-                $this_type = Type::parseString($trimmed);
-                $context->self = $trimmed;
+                $this_type = Type::parseString($scope_fqcn);
+                $context->self = $scope_fqcn;
                 $context->vars_in_scope['$this'] = $this_type;
-                $this->setFQCLN($trimmed);
+                $this->setFQCLN($scope_fqcn);
             }
         }
     }
diff --git a/tests/TypeReconciliation/ScopeTest.php b/tests/TypeReconciliation/ScopeTest.php
index 2ebe26ca274..19d2c0b9520 100644
--- a/tests/TypeReconciliation/ScopeTest.php
+++ b/tests/TypeReconciliation/ScopeTest.php
@@ -215,6 +215,21 @@ function a(): ?int {
                 ?>
                 <h1><?= $this->getMessage() ?></h1>',
             ],
+            'psalmScopeWithNamespace' => [
+                'code' => <<<'PHP'
+                    <?php
+                    namespace A {
+                        class C { public function f(): void {} }
+                    }
+                    namespace B {
+                        use A\C;
+                        /** @psalm-scope-this C */
+                        ?>
+                        <h1><?php $this->f(); ?></h1>
+                        <?php
+                    }
+                    PHP,
+            ],
         ];
     }