From 12aef22f05914bc58c038f48938f888e15dbd763 Mon Sep 17 00:00:00 2001
From: Matthew Brown <github@muglug.com>
Date: Thu, 4 Jan 2018 14:01:17 -0500
Subject: [PATCH] Fix issue where byref differences would not be highlighted

---
 src/Psalm/Checker/FunctionLikeChecker.php | 26 ++++++++++++++++++-----
 tests/MethodSignatureTest.php             | 14 ++++++++++++
 2 files changed, 35 insertions(+), 5 deletions(-)

diff --git a/src/Psalm/Checker/FunctionLikeChecker.php b/src/Psalm/Checker/FunctionLikeChecker.php
index 968e1ad04..ae18863b2 100644
--- a/src/Psalm/Checker/FunctionLikeChecker.php
+++ b/src/Psalm/Checker/FunctionLikeChecker.php
@@ -739,6 +739,8 @@ abstract class FunctionLikeChecker extends SourceChecker implements StatementsSo
                 return null;
             }
 
+            $implementer_param = $implementer_method_storage->params[$i];
+
             $or_null_guide_type = $guide_param->signature_type
                 ? clone $guide_param->signature_type
                 : null;
@@ -748,15 +750,13 @@ abstract class FunctionLikeChecker extends SourceChecker implements StatementsSo
             }
 
             if ($guide_classlike_storage->user_defined
-                && (string)$implementer_method_storage->params[$i]->signature_type
-                    !== (string)$guide_param->signature_type
-                && (string)$implementer_method_storage->params[$i]->signature_type
-                    !== (string)$or_null_guide_type
+                && (string)$implementer_param->signature_type !== (string)$guide_param->signature_type
+                && (string)$implementer_param->signature_type !== (string)$or_null_guide_type
             ) {
                 if (IssueBuffer::accepts(
                     new MethodSignatureMismatch(
                         'Argument ' . ($i + 1) . ' of ' . $cased_implementer_method_id . ' has wrong type \'' .
-                            $implementer_method_storage->params[$i]->signature_type . '\', expecting \'' .
+                            $implementer_param->signature_type . '\', expecting \'' .
                             $guide_param->signature_type . '\' as defined by ' .
                             $cased_guide_method_id,
                         $implementer_method_storage->params[$i]->location
@@ -769,6 +769,22 @@ abstract class FunctionLikeChecker extends SourceChecker implements StatementsSo
                 return null;
             }
 
+            if ($guide_classlike_storage->user_defined && $implementer_param->by_ref !== $guide_param->by_ref) {
+                if (IssueBuffer::accepts(
+                    new MethodSignatureMismatch(
+                        'Argument ' . ($i + 1) . ' of ' . $cased_implementer_method_id . ' is' .
+                            ($implementer_param->by_ref ? '' : ' not') . ' passed by reference, but argument ' .
+                            ($i + 1) . ' of ' . $cased_guide_method_id . ' is' . ($guide_param->by_ref ? '' : ' not'),
+                        $implementer_method_storage->params[$i]->location
+                            ?: $code_location
+                    )
+                )) {
+                    return false;
+                }
+
+                return null;
+            }
+
             $implemeneter_param_type = $implementer_method_storage->params[$i]->type;
 
             if (!$guide_classlike_storage->user_defined &&
diff --git a/tests/MethodSignatureTest.php b/tests/MethodSignatureTest.php
index cc08e935f..4761d71ba 100644
--- a/tests/MethodSignatureTest.php
+++ b/tests/MethodSignatureTest.php
@@ -245,6 +245,20 @@ class MethodSignatureTest extends TestCase
                     function foo($bar = null, $bat) : void {}',
                 'error_message' => 'MisplacedRequiredParam',
             ],
+            'clasginByRef' => [
+                '<?php
+                    class A {
+                      public function foo(string $a) : void {
+                        echo $a;
+                      }
+                    }
+                    class B extends A {
+                      public function foo(string &$a) : void {
+                        echo $a;
+                      }
+                    }',
+                'error_message' => 'MethodSignatureMismatch',
+            ],
         ];
     }
 }