tree-sitter: fix parsing of nested comments, extend tests (#76)

tree_sitter_v/grammar.js

@@ -131,8 +131,17 @@ module.exports = grammar({
 		block_comment: (_) =>
 			seq(
 				'/*',
-				token(choice(/(?:[^/][^*]+\/\*+[^/][^*]+)+(?:[^*][^/]+\*+\/[^*][^/]+)+/, /[^*]*\*/)),
-				'/',
+				repeat(
+					choice(
+						/\*/,
+						regexOr(
+							'[^*]', // any symbol except reserved
+							'[/][^*]', // start of nested comment
+							'[^*][/]', // end of nested comment
+						),
+					),
+				),
+				'*/',
 			),
 
 		comment: ($) => choice($.line_comment, $.block_comment),
@@ -1328,3 +1337,16 @@ function comma_sep1(rules) {
 function comma_sep(rule) {
 	return optional(comma_sep1(rule));
 }
+
+/**
+ * @param {...string} args - One or more regular expression patterns.
+ *
+ * @return {PatternRule}
+ */
+function regexOr(...args) {
+	const regex = args.length > 1 ? args.join('|') : args[0];
+	return {
+		type: 'PATTERN',
+		value: regex,
+	};
+}