Module: TuiTui::Width

Defined in:
lib/tui_tui/width.rb

Overview

Terminal column width for the Unicode ranges this renderer needs. Wide/fullwidth clusters are 2, combining/control clusters are 0.

Constant Summary collapse

WIDE = 
[
  # Hangul Jamo
  [0x1100, 0x115F],
  # CJK radicals, Kangxi, CJK symbols & punctuation
  [0x2E80, 0x303E],
  # Hiragana, Katakana, CJK symbols, enclosed CJK, ...
  [0x3041, 0x33FF],
  # CJK Unified Ext A
  [0x3400, 0x4DBF],
  # CJK Unified Ideographs
  [0x4E00, 0x9FFF],
  # Yi
  [0xA000, 0xA4CF],
  # Hangul Jamo Ext A
  [0xA960, 0xA97F],
  # Hangul Syllables
  [0xAC00, 0xD7A3],
  # CJK Compatibility Ideographs
  [0xF900, 0xFAFF],
  # Vertical forms
  [0xFE10, 0xFE19],
  # CJK Compatibility / small forms
  [0xFE30, 0xFE6F],
  # Fullwidth forms
  [0xFF00, 0xFF60],
  # Fullwidth signs
  [0xFFE0, 0xFFE6],
  # Kana supplement / extended
  [0x1B000, 0x1B16F],
  # Regional indicator symbols (flag letters)
  [0x1F1E6, 0x1F1FF],
  # Enclosed ideographic supplement
  [0x1F200, 0x1F251],
  # Misc symbols & pictographs + emoticons
  [0x1F300, 0x1F64F],
  # Transport & map symbols
  [0x1F680, 0x1F6FF],
  # Supplemental symbols & pictographs
  [0x1F900, 0x1F9FF],
  # Symbols & pictographs extended-A
  [0x1FA70, 0x1FAFF],
  # CJK Unified Ext B and beyond
  [0x20000, 0x3FFFD]
].freeze
ZERO = 
[
  # Combining diacritical marks
  [0x0300, 0x036F],
  [0x0483, 0x0489],
  [0x0591, 0x05BD],
  [0x0610, 0x061A],
  [0x064B, 0x065F],
  [0x06D6, 0x06DC],
  # Zero-width space / joiners / marks
  [0x200B, 0x200F],
  # Variation selectors
  [0xFE00, 0xFE0F],
  # Zero-width no-break space (BOM)
  [0xFEFF, 0xFEFF],
  # Emoji skin-tone modifiers (combine onto the base)
  [0x1F3FB, 0x1F3FF]
].freeze

Class Method Summary collapse

Class Method Details

.char(char) ⇒ Object 



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# File 'lib/tui_tui/width.rb', line 80

def char(char)
  cp = char.ord
  return 0 if control?(cp)
  return 0 if in?(cp, ZERO)

  in?(cp, WIDE) ? 2 : 1
end

.cluster(grapheme) ⇒ Object 



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# File 'lib/tui_tui/width.rb', line 72

def cluster(grapheme)
  # A cluster's base codepoint determines its terminal width.
  base = grapheme[0]
  return 1 if control?(base.ord)

  char(base)
end

.control?(cp) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/tui_tui/width.rb', line 88

def control?(cp)
  cp < 0x20 || cp == 0x7F || cp.between?(0x80, 0x9F)
end