Merge pull request #29 from dejwCake/fix-c1

Fix composer v1 ClassLoader getRegisteredLoaders method missing

Author: Seldaek

src/PackageVersions/Installer.php

@@ -127,7 +127,7 @@ private static function composer2ApiUsable(): bool
             }
         } else {
             $rawData = InstalledVersions::getRawData();
-            if ($rawData === []) {
+            if ($rawData === null || $rawData === []) {
                 return false;
             }
         }

src/PackageVersions/Versions.php

@@ -82,7 +82,7 @@ private static function composer2ApiUsable(): bool
             }
         } else {
             $rawData = InstalledVersions::getRawData();
-            if ($rawData === []) {
+            if ($rawData === null || $rawData === []) {
                 return false;
             }
         }