AppFlowy/app_flowy/lib/workspace/infrastructure/markdown/src/extension_set.dart

import 'block_parser.dart';
import 'inline_parser.dart';

/// ExtensionSets provide a simple grouping mechanism for common Markdown
/// flavors.
///
/// For example, the [gitHubFlavored] set of syntax extensions allows users to
/// output HTML from their Markdown in a similar fashion to GitHub's parsing.
class ExtensionSet {
  ExtensionSet(this.blockSyntaxes, this.inlineSyntaxes);

  /// The [ExtensionSet.none] extension set renders Markdown similar to
  /// [Markdown.pl].
  ///
  /// However, this set does not render _exactly_ the same as Markdown.pl;
  /// rather it is more-or-less the CommonMark standard of Markdown, without
  /// fenced code blocks, or inline HTML.
  ///
  /// [Markdown.pl]: http://daringfireball.net/projects/markdown/syntax
  static final ExtensionSet none = ExtensionSet([], []);

  /// The [commonMark] extension set is close to compliance with [CommonMark].
  ///
  /// [CommonMark]: http://commonmark.org/
  static final ExtensionSet commonMark =
      ExtensionSet([const FencedCodeBlockSyntax()], [InlineHtmlSyntax()]);

  /// The [gitHubWeb] extension set renders Markdown similarly to GitHub.
  ///
  /// This is different from the [gitHubFlavored] extension set in that GitHub
  /// actually renders HTML different from straight [GitHub flavored Markdown].
  ///
  /// (The only difference currently is that [gitHubWeb] renders headers with
  /// linkable IDs.)
  ///
  /// [GitHub flavored Markdown]: https://github.github.com/gfm/
  static final ExtensionSet gitHubWeb = ExtensionSet([
    const FencedCodeBlockSyntax(),
    const HeaderWithIdSyntax(),
    const SetextHeaderWithIdSyntax(),
    const TableSyntax()
  ], [
    InlineHtmlSyntax(),
    StrikethroughSyntax(),
    EmojiSyntax(),
    AutolinkExtensionSyntax(),
  ]);

  /// The [gitHubFlavored] extension set is close to compliance with the [GitHub
  /// flavored Markdown spec].
  ///
  /// [GitHub flavored Markdown]: https://github.github.com/gfm/
  static final ExtensionSet gitHubFlavored = ExtensionSet([
    const FencedCodeBlockSyntax(),
    const TableSyntax()
  ], [
    InlineHtmlSyntax(),
    StrikethroughSyntax(),
    AutolinkExtensionSyntax(),
  ]);

  final List<BlockSyntax> blockSyntaxes;
  final List<InlineSyntax> inlineSyntaxes;
}