Class: Markbridge::Renderers::Discourse::Postprocessor

Inherits:
Object
  • Object
show all
Defined in:
lib/markbridge/renderers/discourse/postprocessor.rb

Overview

Cleans up the raw Markdown produced by the Renderer:

  1. (optional) strips trailing invisible characters per line —NBSP plus the zero-width format chars (ZWSP, ZWNJ, ZWJ, WJ, ZWNBSP/BOM). Deliberately excludes ASCII space and tab so Markdown’s “two trailing spaces = hard line break” rule still works. Off by default.

  2. collapses runs of 3+ newlines down to two,

  3. clears whitespace-only lines,

  4. trims leading/trailing whitespace from the whole document.

Subclass to customize. The call method is the entry point.

Constant Summary collapse

TRAILING_INVISIBLE_RE =

NBSP plus zero-width format chars. Spelled with explicit u{…} escapes rather than the literal characters — the latter are invisible in editors and easy to corrupt on encoding-conversion round-trips.

U+00A0  NBSP        no-break space
U+200B  ZWSP        zero-width space
U+200C  ZWNJ        zero-width non-joiner
U+200D  ZWJ         zero-width joiner
U+2060  WJ          word joiner
U+FEFF  ZWNBSP/BOM  zero-width no-break space / byte-order mark

/[\u{00A0 200B 200C 200D 2060 FEFF}]+$/
DEFAULT = 
new

Instance Method Summary collapse

Constructor Details

#initialize(strip_trailing_invisibles: false) ⇒ Postprocessor

Returns a new instance of Postprocessor.

Parameters:

  • strip_trailing_invisibles (Boolean) (defaults to: false) —

    when true, strips trailing invisible characters (NBSP and zero-width format chars) from each line before the standard cleanup pass.



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# File 'lib/markbridge/renderers/discourse/postprocessor.rb', line 35

def initialize(strip_trailing_invisibles: false)
  @strip_trailing_invisibles = strip_trailing_invisibles
end

Instance Method Details

#call(text) ⇒ String

Parameters:

  • text (String)

Returns:

  • (String) 


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# File 'lib/markbridge/renderers/discourse/postprocessor.rb', line 41

def call(text)
  text = text.gsub(TRAILING_INVISIBLE_RE, "") if @strip_trailing_invisibles
  text
    .gsub(/\n{3,}/, "\n\n") # Max 2 consecutive newlines
    .gsub(/^[ \t]+$/, "") # Remove whitespace-only lines
    .strip # Trim leading/trailing whitespace
end