Class: Banzai::Filter::DollarMathPreFilter

Inherits:
HTML::Pipeline::TextFilter
  • Object
show all
Defined in:
lib/banzai/filter/dollar_math_pre_filter.rb

Overview

HTML filter that implements our dollar math syntax, one of three filters: DollarMathPreFilter, DollarMathPostFilter, and MathFilter

Constant Summary collapse

REGEX =

Display math block: $$ latex math $$

"#{::Gitlab::Regex.markdown_code_or_html_blocks_or_html_comments_untrusted}" \
'|' \
'^\$\$\ *\n' \
'(?P<display_math>' \
'(?:\n|.)*?' \
')' \
'\n\$\$\ *$' \
.freeze

Instance Method Summary collapse

Instance Method Details

#call ⇒ Object 



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# File 'lib/banzai/filter/dollar_math_pre_filter.rb', line 33

def call
  regex = Gitlab::UntrustedRegexp.new(REGEX, multiline: true)
  return @text unless regex.match?(@text)

  regex.replace_gsub(@text) do |match|
    # change from $$ to ```math
    if match[:display_math]
      "```math\n#{match[:display_math]}\n```"
    else
      match.to_s
    end
  end
end