From 8925b4f5969412997b1621ab9e477383ea6399db Mon Sep 17 00:00:00 2001
From: Jordi Boggiano <j.boggiano@seld.be>
Date: Sun, 25 Oct 2020 12:42:35 +0100
Subject: [PATCH 1/2] Attempt fixing handling of root aliases when composer 1
 reads composer 2 lock files, fixes #9337

---
 src/Composer/Package/Locker.php | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/src/Composer/Package/Locker.php b/src/Composer/Package/Locker.php
index 1adc45dc6..93ee6de97 100644
--- a/src/Composer/Package/Locker.php
+++ b/src/Composer/Package/Locker.php
@@ -254,7 +254,17 @@ class Locker
     {
         $lockData = $this->getLockData();
 
-        return isset($lockData['aliases']) ? $lockData['aliases'] : array();
+        if (!isset($lockData['aliases'])) {
+            return array();
+        }
+
+        foreach ($lockData['aliases'] as $index => $alias) {
+            if (in_array($alias['version'], array('dev-master', 'dev-default', 'dev-trunk'), true)) {
+                $lockData['aliases'][$index]['version'] = '9999999-dev';
+            }
+        }
+
+        return $lockData['aliases'];
     }
 
     public function getLockData()

From 04e5d725f48fddf91c92b23b393bb86f2fa97faa Mon Sep 17 00:00:00 2001
From: Jordi Boggiano <j.boggiano@seld.be>
Date: Tue, 27 Oct 2020 20:53:54 +0100
Subject: [PATCH 2/2] Add docs

---
 src/Composer/Package/Locker.php | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/Composer/Package/Locker.php b/src/Composer/Package/Locker.php
index 93ee6de97..f4e82691d 100644
--- a/src/Composer/Package/Locker.php
+++ b/src/Composer/Package/Locker.php
@@ -258,6 +258,8 @@ class Locker
             return array();
         }
 
+        // forward compatibility with Composer 2 lock files created
+        // before https://github.com/composer/composer/issues/9337 was fixed
         foreach ($lockData['aliases'] as $index => $alias) {
             if (in_array($alias['version'], array('dev-master', 'dev-default', 'dev-trunk'), true)) {
                 $lockData['aliases'][$index]['version'] = '9999999-dev';