#2 Use oohology/gitignorewriter to write to gitignore

composer.json

@@ -19,7 +19,8 @@
     "require": {
         "php": ">=7.1",
         "composer/composer": "^1.10",
-        "composer-plugin-api": "^1.0.0"
+        "composer-plugin-api": "^1.0.0",
+        "oohology/gitignorewriter": "^1.1"
     },
     "minimum-stability": "dev",
     "prefer-stable": true,

src/Handler.php

@@ -5,6 +5,7 @@ namespace LakeDrops\DrupalSpoons;
 use Composer\Composer;
 use Composer\IO\IOInterface;
 use Composer\Json\JsonFile;
+use GitIgnoreWriter\GitIgnoreWriter;
 use Symfony\Component\Filesystem\Filesystem;
 
 /**
@@ -68,9 +69,11 @@ class Handler {
     $jsonFile->write($content);
 
     // Add some patterns to .gitignore.
+    $gitignore = new GitIgnoreWriter('.gitignore');
     foreach (['/' . $composerJson, '/' . $composerLock, '/vendor/', '/web/', '/.env'] as $item) {
-      exec('git ignore ' . $item);
+      $gitignore->add($item);
     }
+    $gitignore->save();
   }
 
   /**