From 584344fda3f8f787e10910eb8187f0863ab19a2e Mon Sep 17 00:00:00 2001
From: Vincent Langlet <vincentlanglet@hotmail.fr>
Date: Sun, 30 Jan 2022 15:17:18 +0100
Subject: [PATCH 1/3] Failing test

---
 tests/ReturnTypeProvider/ExceptionCodeTest.php | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/tests/ReturnTypeProvider/ExceptionCodeTest.php b/tests/ReturnTypeProvider/ExceptionCodeTest.php
index ccc8ea10db5..84e8acb28e5 100644
--- a/tests/ReturnTypeProvider/ExceptionCodeTest.php
+++ b/tests/ReturnTypeProvider/ExceptionCodeTest.php
@@ -35,14 +35,23 @@ function f(\PDOException $e): string {
             ',
             [],
         ];
-        yield 'Exception' => [
+        yield 'CustomThrowable' => [
+            '<?php
+                interface CustomThrowable extends \Throwable {}
+
+                /** @var CustomThrowable $e */
+                $code = $e->getCode();
+            ',
+            ['$code' => 'int'],
+        ];
+        yield 'Throwable' => [
             '<?php
                 /** @var \Throwable $e */
                 $code = $e->getCode();
             ',
             ['$code' => 'int|string'],
         ];
-        yield 'Throwable' => [
+        yield 'Exception' => [
             '<?php
                 /** @var \Exception $e */
                 $code = $e->getCode();

From cd3213201d1cbccd3aa1bc4892fc4b2a3cadd60b Mon Sep 17 00:00:00 2001
From: Vincent Langlet <vincentlanglet@hotmail.fr>
Date: Sun, 30 Jan 2022 15:30:40 +0100
Subject: [PATCH 2/3] Fix

---
 .../Expression/Call/Method/MethodCallReturnTypeFetcher.php  | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/Psalm/Internal/Analyzer/Statements/Expression/Call/Method/MethodCallReturnTypeFetcher.php b/src/Psalm/Internal/Analyzer/Statements/Expression/Call/Method/MethodCallReturnTypeFetcher.php
index c4779156a9e..9f8abaa7973 100644
--- a/src/Psalm/Internal/Analyzer/Statements/Expression/Call/Method/MethodCallReturnTypeFetcher.php
+++ b/src/Psalm/Internal/Analyzer/Statements/Expression/Call/Method/MethodCallReturnTypeFetcher.php
@@ -97,7 +97,11 @@ public static function fetch(
 
         if ($premixin_method_id->method_name === 'getcode'
             && $premixin_method_id->fq_class_name !== Exception::class
-            && in_array(Throwable::class, $class_storage->class_implements)) {
+            && (
+                in_array(Throwable::class, $class_storage->class_implements)
+                || $codebase->interfaceExtends($premixin_method_id->fq_class_name, Throwable::class)
+            )
+        ) {
             if ($premixin_method_id->fq_class_name === PDOException::class) {
                 return Type::getString();
             } else {

From 854a3412fe58643b243f65f32a10df191ab409f9 Mon Sep 17 00:00:00 2001
From: Vincent Langlet <vincentlanglet@hotmail.fr>
Date: Sun, 30 Jan 2022 15:32:55 +0100
Subject: [PATCH 3/3] Use function

---
 .../Expression/Call/Method/MethodCallReturnTypeFetcher.php      | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Psalm/Internal/Analyzer/Statements/Expression/Call/Method/MethodCallReturnTypeFetcher.php b/src/Psalm/Internal/Analyzer/Statements/Expression/Call/Method/MethodCallReturnTypeFetcher.php
index 9f8abaa7973..a5dc24d171c 100644
--- a/src/Psalm/Internal/Analyzer/Statements/Expression/Call/Method/MethodCallReturnTypeFetcher.php
+++ b/src/Psalm/Internal/Analyzer/Statements/Expression/Call/Method/MethodCallReturnTypeFetcher.php
@@ -98,7 +98,7 @@ public static function fetch(
         if ($premixin_method_id->method_name === 'getcode'
             && $premixin_method_id->fq_class_name !== Exception::class
             && (
-                in_array(Throwable::class, $class_storage->class_implements)
+                $codebase->classImplements($premixin_method_id->fq_class_name, Throwable::class)
                 || $codebase->interfaceExtends($premixin_method_id->fq_class_name, Throwable::class)
             )
         ) {