提交: f00309f94962bce86a760ecd7c103afa79ed9010 - luce (git)

A Markdown shard for the Crystal programming language

Commit MetaInfo

• 修訂: f00309f94962bce86a760ecd7c103afa79ed9010 (tree)
• 時間: 2023-12-28 12:19:51
• 作者: supercell <stigma@disr...>
• Commiter: supercell

Log Message

Add support for AlertBlockSyntaxes

Change Summary

• modified: CHANGELOG.md
• add: spec/extensions/alert_extension.unit
• modified: spec/luce_spec.cr
• modified: src/luce.cr
• add: src/luce/block_syntaxes/alert_block_syntax.cr
• modified: src/luce/extension_set.cr
• modified: src/luce/patterns.cr

差異

--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,7 @@ All notable changes to Luce will be documented in this file.
 ## [Unreleased]
 
 * Support for [footnotes](https://pandoc.org/MANUAL.html#footnotes).
+* Support for [Github Alerts][gh-alerts]
 * Tables are now able to interrupt other blocks.
 * Allow Element attributes to have no value ([#6][issue-6] - thanks [solvin]!).
 * Fix an infinite loop occurring when using a link in table headers.
@@ -16,6 +17,7 @@ All notable changes to Luce will be documented in this file.
   ([#3][issue-3] - thanks [solvin]!)
 * Fix crash in Crystal >=1.8 caused by exceeding the Regex Match Limit.
 
+[gh-alerts]: https://docs.github.com/get-started/writing-on-github/getting-started-with-writing-and-formatting-on-github/basic-writing-and-formatting-syntax#alerts
 [issue-3]: https://codeberg.org/supercell/luce/pulls/3
 [issue-6]: https://codeberg.org/supercell/luce/pulls/6
 [solvin]: https://codeberg.org/solvin

--- /dev/null
+++ b/spec/extensions/alert_extension.unit
@@ -0,0 +1,94 @@
+>>> type note
+> [!NoTe]
+> Test note alert.
+<<<
+<div class="markdown-alert markdown-alert-note">
+<p class="markdown-alert-title">Note</p>
+<p>Test note alert.</p>
+</div>
+>>> type tip
+> [!TiP]
+> Test tip alert.
+<<<
+<div class="markdown-alert markdown-alert-tip">
+<p class="markdown-alert-title">Tip</p>
+<p>Test tip alert.</p>
+</div>
+>>> type important
+> [!ImpoRtanT]
+> Test important alert.
+<<<
+<div class="markdown-alert markdown-alert-important">
+<p class="markdown-alert-title">Important</p>
+<p>Test important alert.</p>
+</div>
+>>> type warning
+> [!WarNinG]
+> Test warning alert.
+<<<
+<div class="markdown-alert markdown-alert-warning">
+<p class="markdown-alert-title">Warning</p>
+<p>Test warning alert.</p>
+</div>
+>>> type caution
+> [!CauTioN]
+> Test caution alert.
+<<<
+<div class="markdown-alert markdown-alert-caution">
+<p class="markdown-alert-title">Caution</p>
+<p>Test caution alert.</p>
+</div>
+>>> invalid type
+> [!foo]
+> Test foo alert.
+<<<
+<blockquote>
+<p>[!foo]
+Test foo alert.</p>
+</blockquote>
+>>> contents can both contain/not contain starting quote
+> [!NOTE]
+Test note alert.
+>Test note alert x2.
+<<<
+<div class="markdown-alert markdown-alert-note">
+<p class="markdown-alert-title">Note</p>
+<p>Test note alert.
+Test note alert x2.</p>
+</div>
+>>> spaces everywhere
+ >  [!NOTE]
+>   Test note alert.
+  > Test note alert x2.
+<<<
+<div class="markdown-alert markdown-alert-note">
+<p class="markdown-alert-title">Note</p>
+<p>Test note alert.
+Test note alert x2.</p>
+</div>
+>>> title has 3 more spaces then fallback to blockquote
+>    [!NOTE]
+>   Test blockquote.
+<<<
+<blockquote>
+<p>[!NOTE]
+Test blockquote.</p>
+</blockquote>
+>>>nested blockquote
+> [!NOTE]
+>> Test nested blockquote.
+<<<
+<div class="markdown-alert markdown-alert-note">
+<p class="markdown-alert-title">Note</p>
+<blockquote>
+<p>Test nested blockquote.</p>
+</blockquote>
+</div>
+>>>escape brackets
+> \[!note\]
+> Test escape brackets.
+<<<
+<div class="markdown-alert markdown-alert-note">
+<p class="markdown-alert-title">Note</p>
+<p>Test escape brackets.</p>
+</div>

--- a/spec/luce_spec.cr
+++ b/spec/luce_spec.cr
@@ -97,6 +97,8 @@ test_file "extensions/unordered_list_with_checkboxes.unit",
   block_syntaxes: [Luce::UnorderedListWithCheckboxSyntax.new]
 test_file "extensions/footnote_block.unit",
   block_syntaxes: [Luce::FootnoteDefSyntax.new]
+test_file "extensions/alert_extension.unit",
+  block_syntaxes: [Luce::AlertBlockSyntax.new]
 
 # Inline syntax extensions
 test_file "extensions/autolink_extension.unit",

--- a/src/luce.cr
+++ b/src/luce.cr
@@ -5,6 +5,7 @@
 #
 require "./luce/ast"
 require "./luce/block_parser"
+require "./luce/block_syntaxes/alert_block_syntax"
 require "./luce/block_syntaxes/block_syntax"
 require "./luce/block_syntaxes/blockquote_syntax"
 require "./luce/block_syntaxes/code_block_syntax"

--- /dev/null
+++ b/src/luce/block_syntaxes/alert_block_syntax.cr
@@ -0,0 +1,94 @@
+#
+# Copyright (c) 2023 supercell
+#
+# SPDX-License-Identifier: BSD-3-Clause
+#
+require "./block_syntax"
+
+# Parses GitHub Alert blocks
+#
+# See also: https://docs.github.com/get-started/writing-on-github/getting-started-with-writing-and-formatting-on-github/basic-writing-and-formatting-syntax#alerts
+module Luce
+  class AlertBlockSyntax < BlockSyntax
+    # Whether this alert ends with a lazy continuation line.
+    #
+    # The definition of lazy continuation lines:
+    # https://spec.commonmark.org/0.30/#lazy-continuation-line
+    @lazy_continuation = false
+    @content_line_regexp = Regex.new(%q{>?\s?(.*)*})
+
+    def pattern : Regex
+      Luce.alert_pattern
+    end
+
+    def can_parse?(parser : BlockParser) : Bool
+      pattern.matches?(parser.current.content) && parser.lines.any?(&.content.matches?(@content_line_regexp))
+    end
+
+    def parse_child_lines(parser : BlockParser) : Array(Line)
+      # Grab all of the lines that form the alert, stripping off the ">".
+      child_lines = [] of Line
+      @lazy_continuation = false
+
+      until parser.done?
+        stripped_content = parser.current.content.sub(/^\s*>?\s*/, "")
+        match = @content_line_regexp.match(stripped_content)
+        unless match.nil?
+          child_lines << Line.new(stripped_content)
+          parser.advance
+          @lazy_continuation = false
+          next
+        end
+
+        last_line = child_lines.last
+
+        # A paragraph continuation is OK. This is content that cannot be parsed
+        # as any other syntax except Paragraph, and it doesn't match the bar in
+        # a Setext Header.
+        # Because indented code blocks cannot interrupt paragraphs, a line
+        # matched CodeBlockSyntax is also paragraph continuation text.
+        other_matched = parser.block_syntaxes.find(&.can_parse?(parser))
+        if (other_matched.is_a?(ParagraphSyntax) && !last_line.is_blank_line? && !Luce.code_fence_pattern.matches?(last_line.content)) ||
+           (other_matched.is_a?(CodeBlockSyntax) && !Luce.indent_pattern.matches?(last_line.content))
+          child_lines << parser.current
+          @lazy_continuation = true
+          parser.advance
+        else
+          break
+        end
+      end
+
+      child_lines
+    end
+
+    def parse(parser : BlockParser) : Node?
+      # Parse the alert type from the first line.
+      type = pattern.match(parser.current.content).not_nil![1].not_nil!.downcase
+      parser.advance
+      child_lines = parse_child_lines(parser)
+      # Recursively parse the contents of the alert.
+      children = BlockParser.new(child_lines, parser.document).parse_lines(
+        # The setext heading underline cannot be a lazy continuation line in a
+        # block quote.
+        # https://spec.commonmark.org/0.30/#example-93
+        disable_setext_heading: @lazy_continuation,
+        parent_syntax: self)
+
+      # Mapping the alert title text.
+      type_text_map = {
+        "note"      => "Note",
+        "tip"       => "Tip",
+        "important" => "Important",
+        "caution"   => "Caution",
+        "warning"   => "Warning",
+      }
+      title_text = type_text_map[type]
+      title_element = Element.new("p", [Text.new(title_text)] of Node)
+      title_element.attributes["class"] = "markdown-alert-title"
+      element_class = "markdown-alert markdown-alert-#{type.downcase}"
+      element = Element.new("div", [title_element] + children)
+      element.attributes["class"] = element_class
+      element
+    end
+  end
+end

--- a/src/luce/extension_set.cr
+++ b/src/luce/extension_set.cr
@@ -44,6 +44,7 @@ module Luce
         UnorderedListWithCheckboxSyntax.new,
         OrderedListWithCheckboxSyntax.new,
         FootnoteDefSyntax.new,
+        AlertBlockSyntax.new,
       ],
       [
         InlineHTMLSyntax.new,

--- a/src/luce/patterns.cr
+++ b/src/luce/patterns.cr
@@ -85,8 +85,13 @@ module Luce
   @@html_characters_pattern = Regex.new("&(?:([a-z0-9]+)|#([0-9]{1,7})|#x([a-f0-9]{1,6}));",
     Regex::Options::IGNORE_CASE)
 
+  # :nodoc:
   @@link_reference_definition_pattern = Regex.new(%q{^[ ]{0,3}\[})
 
+  # :nodoc:
+  @@alert_pattern = Regex.new(%q{^\s{0,3}>\s{0,3}\\?\[!(note|tip|important|caution|warning)\\?\]\s*$},
+    Regex::Options::IGNORE_CASE)
+
   # The line contains only whitespace or is empty
   def self.empty_pattern : Regex
     @@empty_pattern
@@ -197,4 +202,12 @@ module Luce
   def self.link_reference_definition_pattern : Regex
     @@link_reference_definition_pattern
   end
+
+  # Alert type patterns.
+  # A alert block is similar to a blockquote,
+  # starts with `> [!TYPE]`, and only 5 types are supported
+  # with case-insensitive.
+  def self.alert_pattern : Regex
+    @@alert_pattern
+  end
 end