From 5f202efa0bcf8f51f13ab073a09b42ebfb6c8f26 Mon Sep 17 00:00:00 2001
From: Andreas Schempp <andreas.schempp@terminal42.ch>
Date: Wed, 16 Oct 2019 13:36:28 +0200
Subject: [PATCH] Added comment why source link check is necessary

---
 src/Composer/Repository/BaseRepository.php | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/Composer/Repository/BaseRepository.php b/src/Composer/Repository/BaseRepository.php
index 5ee866543..d668f43cb 100644
--- a/src/Composer/Repository/BaseRepository.php
+++ b/src/Composer/Repository/BaseRepository.php
@@ -68,6 +68,9 @@ abstract class BaseRepository implements RepositoryInterface
             if (!$invert) {
                 $links += $package->getReplaces();
 
+                // On forward search, check if any replaced package was required and add the replaced
+                // packages to the list of needles. Contrary to the cross-reference link check below,
+                // replaced packages are the target of links.
                 foreach ($package->getReplaces() as $link) {
                     foreach ($needles as $needle) {
                         if ($link->getSource() === $needle) {