# frozen_string_literal: true ## # A collection of text-wrangling methods module Gem::Text ## # Remove any non-printable characters and make the text suitable for # printing. def clean_text(text) text.gsub(/[\000-\b\v-\f\016-\037\177]/, ".".freeze) end def truncate_text(text, description, max_length = 100_000) raise ArgumentError, "max_length must be positive" unless max_length > 0 return text if text.size <= max_length "Truncating #{description} to #{max_length.to_s.reverse.gsub(/...(?=.)/,'\&,').reverse} characters:\n" + text[0, max_length] end ## # Wraps +text+ to +wrap+ characters and optionally indents by +indent+ # characters def format_text(text, wrap, indent=0) result = [] work = clean_text(text) while work.length > wrap do if work =~ /^(.{0,#{wrap}})[ \n]/ result << $1.rstrip work.slice!(0, $&.length) else result << work.slice!(0, wrap) end end result << work if work.length.nonzero? result.join("\n").gsub(/^/, " " * indent) end def min3(a, b, c) # :nodoc: if a < b && a < c a elsif b < c b else c end end # This code is based directly on the Text gem implementation # Returns a value representing the "cost" of transforming str1 into str2 def levenshtein_distance(str1, str2) s = str1 t = str2 n = s.length m = t.length return m if (0 == n) return n if (0 == m) d = (0..m).to_a x = nil str1.each_char.each_with_index do |char1,i| e = i + 1 str2.each_char.each_with_index do |char2,j| cost = (char1 == char2) ? 0 : 1 x = min3( d[j + 1] + 1, # insertion e + 1, # deletion d[j] + cost # substitution ) d[j] = e e = x end d[m] = x end return x end end