src/vs/editor/common/languages/languageConfigurationRegistry.ts/ResolvedLanguageConfiguration/_handleComments
class ResolvedLanguageConfiguration:	private static _handleComments(
		conf: LanguageConfiguration
	): ICommentsConfiguration | null {
		const commentRule = conf.comments;
		if (!commentRule) {
			return null;
		}

		// comment configuration
		const comments: ICommentsConfiguration = {};

		if (commentRule.lineComment) {
			comments.lineCommentToken = commentRule.lineComment;
		}
		if (commentRule.blockComment) {
			const [blockStart, blockEnd] = commentRule.blockComment;
			comments.blockCommentStartToken = blockStart;
			comments.blockCommentEndToken = blockEnd;
		}

		return comments;
	}