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ruby--ruby/lib/rubygems/text.rb

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# 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
# Returns a value representing the "cost" of transforming str1 into str2
# Vendored version of DidYouMean::Levenshtein.distance from the ruby/did_you_mean gem @ 1.4.0
# https://git.io/JJgZI
def levenshtein_distance(str1, str2)
n = str1.length
m = str2.length
return m if n.zero?
return n if m.zero?
d = (0..m).to_a
x = nil
# to avoid duplicating an enumerable object, create it outside of the loop
str2_codepoints = str2.codepoints
str1.each_codepoint.with_index(1) do |char1, i|
j = 0
while j < m
cost = (char1 == str2_codepoints[j]) ? 0 : 1
x = min3(
d[j + 1] + 1, # insertion
i + 1, # deletion
d[j] + cost # substitution
)
d[j] = i
i = x
j += 1
end
d[m] = x
end
x
end
end