[#25] Invalid Version: [[]] when no tag can be found

If no matching tag can be found, the semver library still attempts to create a tag with the string "". This in turn generates an exception, which is now caught, and we return null to indicate that no tag was found.

Author: tomzx

src/PHPSemVerCheckerGit/Console/Command/SuggestCommand.php

@@ -184,7 +184,14 @@ protected function findTag(Repository $repository, $tag)
 
 		$tagExpression = new SemanticExpression($tag);
 
-		return $this->getMappedVersionTag($tags, $tagExpression->maxSatisfying($tags));
+		try {
+			// Throws an exception if it cannot find a matching version
+			$satisfyingTag = $tagExpression->maxSatisfying($tags);
+		} catch (SemanticVersionException $e) {
+			return null;
+		}
+
+		return $this->getMappedVersionTag($tags, $satisfyingTag);
 	}
 
 	private function filterTags(array $tags)