| // Copyright (c) 2022, the Dart project authors. Please see the AUTHORS file |
| // for details. All rights reserved. Use of this source code is governed by a |
| // BSD-style license that can be found in the LICENSE file. |
| |
| import '../ast.dart'; |
| import '../charcode.dart'; |
| import '../inline_parser.dart'; |
| import '../util.dart'; |
| import 'inline_syntax.dart'; |
| |
| /// Matches backtick-enclosed inline code blocks. |
| class CodeSyntax extends InlineSyntax { |
| // This pattern matches: |
| // |
| // * a string of backticks (not followed by any more), followed by |
| // * a non-greedy string of anything, including newlines, ending with anything |
| // except a backtick, followed by |
| // * a string of backticks the same length as the first, not followed by any |
| // more. |
| // |
| // This conforms to the delimiters of inline code, both in Markdown.pl, and |
| // CommonMark. |
| static final String _pattern = r'(`+(?!`))((?:.|\n)*?[^`])\1(?!`)'; |
| |
| CodeSyntax() : super(_pattern); |
| |
| @override |
| bool tryMatch(InlineParser parser, [int? startMatchPos]) { |
| if (parser.pos > 0 && parser.charAt(parser.pos - 1) == $backquote) { |
| // Not really a match! We can't just sneak past one backtick to try the |
| // next character. An example of this situation would be: |
| // |
| // before ``` and `` after. |
| // ^--parser.pos |
| return false; |
| } |
| |
| final match = pattern.matchAsPrefix(parser.source, parser.pos); |
| if (match == null) { |
| return false; |
| } |
| parser.writeText(); |
| if (onMatch(parser, match)) parser.consume(match.match.length); |
| return true; |
| } |
| |
| @override |
| bool onMatch(InlineParser parser, Match match) { |
| var code = match[2]!.trim().replaceAll('\n', ' '); |
| if (parser.encodeHtml) code = escapeHtml(code); |
| parser.addNode(Element.text('code', code)); |
| |
| return true; |
| } |
| } |