From c5a15d559ab3cdab1d8a602f714a05feb3e00145 Mon Sep 17 00:00:00 2001
From: Leonardo Losoviz <leo@getpop.org>
Date: Mon, 14 Dec 2020 19:41:36 +0800
Subject: [PATCH] [Downgrade] Fix parameter type widening issue, when method
 lives on the ancestor's interface (#4877)

Co-authored-by: rector-bot <tomas@getrector.org>
---
 .../DowngradeParameterTypeWideningRector.php  | 15 +++++-
 .../Fixture/interface_on_parent_class.php.inc | 48 +++++++++++++++++++
 2 files changed, 62 insertions(+), 1 deletion(-)
 create mode 100644 rules/downgrade-php72/tests/Rector/ClassMethod/DowngradeParameterTypeWideningRector/Fixture/interface_on_parent_class.php.inc

diff --git a/rules/downgrade-php72/src/Rector/ClassMethod/DowngradeParameterTypeWideningRector.php b/rules/downgrade-php72/src/Rector/ClassMethod/DowngradeParameterTypeWideningRector.php
index c543031b28b..b9d207667ff 100644
--- a/rules/downgrade-php72/src/Rector/ClassMethod/DowngradeParameterTypeWideningRector.php
+++ b/rules/downgrade-php72/src/Rector/ClassMethod/DowngradeParameterTypeWideningRector.php
@@ -150,8 +150,21 @@ CODE_SAMPLE
         foreach ($ancestorAndInterfaceClassNames as $ancestorClassOrInterface) {
             /** @var string */
             $parentClassName = $ancestorClassOrInterface->getAttribute(AttributeKey::CLASS_NAME);
-            /** @var ClassMethod */
             $classMethod = $this->nodeRepository->findClassMethod($parentClassName, $methodName);
+            /**
+             * If it doesn't find the method, it's because the method
+             * lives somewhere else.
+             * For instance, in test "interface_on_parent_class.php.inc",
+             * the ancestor abstract class is also retrieved
+             * as containing the method, but it does not: it is
+             * in its implemented interface. That happens because
+             * `ReflectionMethod` doesn't allow to do do the distinction.
+             * The interface is also retrieve though, so that method
+             * will eventually be refactored.
+             */
+            if ($classMethod === null) {
+                continue;
+            }
             $this->removeParamTypeFromMethod($ancestorClassOrInterface, $position, $classMethod);
             $this->removeParamTypeFromMethodForChildren($parentClassName, $methodName, $position);
         }
diff --git a/rules/downgrade-php72/tests/Rector/ClassMethod/DowngradeParameterTypeWideningRector/Fixture/interface_on_parent_class.php.inc b/rules/downgrade-php72/tests/Rector/ClassMethod/DowngradeParameterTypeWideningRector/Fixture/interface_on_parent_class.php.inc
new file mode 100644
index 00000000000..6550916a16a
--- /dev/null
+++ b/rules/downgrade-php72/tests/Rector/ClassMethod/DowngradeParameterTypeWideningRector/Fixture/interface_on_parent_class.php.inc
@@ -0,0 +1,48 @@
+<?php
+
+namespace Rector\DowngradePhp72\Tests\Rector\ClassMethod\DowngradeParameterTypeWideningRector\Fixture;
+
+interface SomeInterface
+{
+    public function test(string $input);
+}
+
+abstract class AbstractSomeAncestorClass implements SomeInterface
+{
+}
+
+class SomeChildClass extends AbstractSomeAncestorClass
+{
+    public function test($input) // type omitted for $input
+    {
+        /* ... */
+    }
+}
+
+?>
+-----
+<?php
+
+namespace Rector\DowngradePhp72\Tests\Rector\ClassMethod\DowngradeParameterTypeWideningRector\Fixture;
+
+interface SomeInterface
+{
+    /**
+     * @param string $input
+     */
+    public function test($input);
+}
+
+abstract class AbstractSomeAncestorClass implements SomeInterface
+{
+}
+
+class SomeChildClass extends AbstractSomeAncestorClass
+{
+    public function test($input) // type omitted for $input
+    {
+        /* ... */
+    }
+}
+
+?>