Fix type error in ArchiverInterface::supports(), fixes #10702

src/Composer/Package/Archiver/ArchiverInterface.php

@@ -36,9 +36,9 @@ interface ArchiverInterface
      * Format supported by the archiver.
      *
      * @param string $format     The archive format
-     * @param string $sourceType The source type (git, svn, hg, etc.)
+     * @param ?string $sourceType The source type (git, svn, hg, etc.)
      *
      * @return bool true if the format is supported by the archiver
      */
-    public function supports(string $format, string $sourceType): bool;
+    public function supports(string $format, ?string $sourceType): bool;
 }

src/Composer/Package/Archiver/PharArchiver.php

@@ -97,7 +97,7 @@ class PharArchiver implements ArchiverInterface
     /**
      * @inheritDoc
      */
-    public function supports(string $format, string $sourceType): bool
+    public function supports(string $format, ?string $sourceType): bool
     {
         return isset(static::$formats[$format]);
     }

src/Composer/Package/Archiver/ZipArchiver.php

@@ -78,7 +78,7 @@ class ZipArchiver implements ArchiverInterface
     /**
      * @inheritDoc
      */
-    public function supports(string $format, string $sourceType): bool
+    public function supports(string $format, ?string $sourceType): bool
     {
         return isset(static::$formats[$format]) && $this->compressionAvailable();
     }