From 69e556fe060540070c59e26a952a0abc49a097e9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?J=C3=A9r=C3=B4me=20Tamarelle?= <jerome@tamarelle.net>
Date: Thu, 2 Apr 2026 23:23:09 +0200
Subject: [PATCH] Fix "null as array offset" deprecation in
 DockerComposeConfigurator

Since 33ce7c1, new compose.yaml files are created empty instead of being
seeded with "version: '3'\n". When the file is empty, the parsing loop
finds no top-level keys and $node stays null, causing "Using null as an
array offset" deprecations when $endAt[$node] is written.

Guard both assignments with `null !== $node` checks.
---
 src/Configurator/DockerComposeConfigurator.php | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/src/Configurator/DockerComposeConfigurator.php b/src/Configurator/DockerComposeConfigurator.php
index 5314aa7f..e1f07c33 100644
--- a/src/Configurator/DockerComposeConfigurator.php
+++ b/src/Configurator/DockerComposeConfigurator.php
@@ -275,7 +275,9 @@ private function configureDockerCompose(Recipe $recipe, array $config, bool $upd
                 }
 
                 // Keep end in memory (check break line on previous line)
-                $endAt[$node] = !$i || '' !== trim($lines[$i - 1]) ? $i : $i - 1;
+                if (null !== $node) {
+                    $endAt[$node] = !$i || '' !== trim($lines[$i - 1]) ? $i : $i - 1;
+                }
                 $node = $matches[1];
                 if (!isset($nodesLines[$node])) {
                     $nodesLines[$node] = [];
@@ -285,7 +287,9 @@ private function configureDockerCompose(Recipe $recipe, array $config, bool $upd
                     $startAt[$node] = $i + 1;
                 }
             }
-            $endAt[$node] = \count($lines) + 1;
+            if (null !== $node) {
+                $endAt[$node] = \count($lines) + 1;
+            }
 
             foreach ($extra as $key => $value) {
                 if (isset($endAt[$key])) {