Add bin and edit workflow

bin/gems/kramdown-2.5.2/lib/kramdown/parser/base.rb

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+# -*- coding: utf-8; frozen_string_literal: true -*-
+#
+#--
+# Copyright (C) 2009-2026 Thomas Leitner <t_leitner@gmx.at>
+#
+# This file is part of kramdown which is licensed under the MIT.
+#++
+#
+
+require 'kramdown/utils'
+require 'kramdown/parser'
+
+module Kramdown
+
+  module Parser
+
+    # == \Base class for parsers
+    #
+    # This class serves as base class for parsers. It provides common methods that can/should be
+    # used by all parsers, especially by those using StringScanner(Kramdown) for parsing.
+    #
+    # A parser object is used as a throw-away object, i.e. it is only used for storing the needed
+    # state information during parsing. Therefore one can't instantiate a parser object directly but
+    # only use the Base::parse method.
+    #
+    # == Implementing a parser
+    #
+    # Implementing a new parser is rather easy: just derive a new class from this class and put it
+    # in the Kramdown::Parser module -- the latter is needed so that the auto-detection of the new
+    # parser works correctly. Then you need to implement the +#parse+ method which has to contain
+    # the parsing code.
+    #
+    # Have a look at the Base::parse, Base::new and Base#parse methods for additional information!
+    class Base
+
+      # The hash with the parsing options.
+      attr_reader :options
+
+      # The array with the parser warnings.
+      attr_reader :warnings
+
+      # The original source string.
+      attr_reader :source
+
+      # The root element of element tree that is created from the source string.
+      attr_reader :root
+
+      # Initialize the parser object with the +source+ string and the parsing +options+.
+      #
+      # The @root element, the @warnings array and @text_type (specifies the default type for newly
+      # created text nodes) are automatically initialized.
+      def initialize(source, options)
+        @source = source
+        @options = Kramdown::Options.merge(options)
+        @root = Element.new(:root, nil, nil, encoding: (source.encoding rescue nil), location: 1,
+                            options: {}, abbrev_defs: {}, abbrev_attr: {})
+
+        @root.options[:abbrev_defs].default_proc = @root.options[:abbrev_attr].default_proc =
+          lambda do |h, k|
+            k_mod = k.gsub(/[\s\p{Z}]+/, " ")
+            k != k_mod ? h[k_mod] : nil
+          end
+        @warnings = []
+        @text_type = :text
+      end
+      private_class_method(:new, :allocate)
+
+      # Parse the +source+ string into an element tree, possibly using the parsing +options+, and
+      # return the root element of the element tree and an array with warning messages.
+      #
+      # Initializes a new instance of the calling class and then calls the +#parse+ method that must
+      # be implemented by each subclass.
+      def self.parse(source, options = {})
+        parser = new(source, options)
+        parser.parse
+        [parser.root, parser.warnings]
+      end
+
+      # Parse the source string into an element tree.
+      #
+      # The parsing code should parse the source provided in @source and build an element tree the
+      # root of which should be @root.
+      #
+      # This is the only method that has to be implemented by sub-classes!
+      def parse
+        raise NotImplementedError
+      end
+
+      # Add the given warning +text+ to the warning array.
+      def warning(text)
+        @warnings << text
+        # TODO: add position information
+      end
+
+      # Modify the string +source+ to be usable by the parser (unifies line ending characters to
+      # +\n+ and makes sure +source+ ends with a new line character).
+      def adapt_source(source)
+        unless source.valid_encoding?
+          raise "The source text contains invalid characters for the used encoding #{source.encoding}"
+        end
+        source = source.encode('UTF-8')
+        source.gsub!(/\r\n?/, "\n")
+        source.chomp!
+        source << "\n"
+      end
+
+      # This helper method adds the given +text+ either to the last element in the +tree+ if it is a
+      # +type+ element or creates a new text element with the given +type+.
+      def add_text(text, tree = @tree, type = @text_type)
+        last = tree.children.last
+        if last && last.type == type
+          last.value << text
+        elsif !text.empty?
+          location = (last && last.options[:location] || tree.options[:location])
+          tree.children << Element.new(type, text, nil, location: location)
+        end
+      end
+
+      # Extract the part of the StringScanner +strscan+ backed string specified by the +range+. This
+      # method works correctly under Ruby 1.8 and Ruby 1.9.
+      def extract_string(range, strscan)
+        result = nil
+        begin
+          enc = strscan.string.encoding
+          strscan.string.force_encoding('ASCII-8BIT')
+          result = strscan.string[range].force_encoding(enc)
+        ensure
+          strscan.string.force_encoding(enc)
+        end
+        result
+      end
+
+    end
+
+  end
+
+end