Module: TableTennis::Util::Strings

Includes:
MemoWise
Defined in:
lib/table_tennis/util/strings.rb

Overview

Helpers for measuring and truncating strings.

Constant Summary collapse

ANSI_CODE = 
/\e\[[0-9;]*m/
ELLIPSIS = 
"…"
INVISIBLE = 
/\A(\e\[[0-9;]*m|\u200B)*\z/
SIMPLE =

note that escape \e (0x1b) is excluded

/\A[\x00-\x1a\x1c-\x7F–—…·‘’“”•áéíñóúÓ]*\Z/

Class Method Summary collapse

Class Method Details

.center(str, width) ⇒ Object

center text, like String#center but works with painted strings



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# File 'lib/table_tennis/util/strings.rb', line 38

def center(str, width)
  # artificially inflate width to include escape codes
  if painted?(str)
    width += str.length - unpaint(str).length
  end
  str.center(width)
end

.hyperlink(str) ⇒ Object 



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# File 'lib/table_tennis/util/strings.rb', line 46

def hyperlink(str)
  # fail fast, for speed
  return unless str.length >= 6 && str[0] == "["
  if str =~ /^\[(.*)\]\((.*)\)$/
    [$1, $2]
  end
end

.painted?(str) ⇒ Boolean

does this string contain ansi codes?

Returns:

  • (Boolean) 


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# File 'lib/table_tennis/util/strings.rb', line 12

def painted?(str) = str.match?(/\e/)

.titleize(str) ⇒ Object

similar to rails titleize



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# File 'lib/table_tennis/util/strings.rb', line 18

def titleize(str)
  str = str.gsub(/_id$/, "") # remove _id
  str = str.tr("_", " ") # remove underscores
  str = str.gsub(/(\w)([A-Z])/, '\1 \2') # OneTwo => One Two
  str = str.split.map(&:capitalize).join(" ") # capitalize
  str
end

.truncate(str, stop) ⇒ Object

Truncate a string based on the display width of characters. Does not attempt to handle graphemes. Should handle emojis and international characters. Painted strings too.



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# File 'lib/table_tennis/util/strings.rb', line 60

def truncate(str, stop)
  if str.bytesize <= stop
    str
  elsif simple?(str)
    (str.length <= stop) ? str : "#{str[0, stop - 1]}#{ELLIPSIS}"
  else
    truncate0(str, stop)
  end
end

.unpaint(str) ⇒ Object

strip ansi codes



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# File 'lib/table_tennis/util/strings.rb', line 15

def unpaint(str) = str.gsub(ANSI_CODE, "")

.width(str) ⇒ Object

measure width of text, with support for emojis, painted/ansi strings, etc



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# File 'lib/table_tennis/util/strings.rb', line 27

def width(str)
  if simple?(str)
    str.length
  elsif painted?(str)
    unpaint(str).length
  else
    Unicode::DisplayWidth.of(str)
  end
end