87 lines
2.0 KiB
Ruby
87 lines
2.0 KiB
Ruby
# frozen_string_literal: true
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##
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# A collection of text-wrangling methods
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module Gem::Text
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##
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# Remove any non-printable characters and make the text suitable for
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# printing.
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def clean_text(text)
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text.gsub(/[\000-\b\v-\f\016-\037\177]/, ".".freeze)
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end
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def truncate_text(text, description, max_length = 100_000)
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raise ArgumentError, "max_length must be positive" unless max_length > 0
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return text if text.size <= max_length
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"Truncating #{description} to #{max_length.to_s.reverse.gsub(/...(?=.)/,'\&,').reverse} characters:\n" + text[0, max_length]
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end
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##
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# Wraps +text+ to +wrap+ characters and optionally indents by +indent+
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# characters
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def format_text(text, wrap, indent=0)
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result = []
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work = clean_text(text)
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while work.length > wrap do
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if work =~ /^(.{0,#{wrap}})[ \n]/
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result << $1.rstrip
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work.slice!(0, $&.length)
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else
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result << work.slice!(0, wrap)
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end
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end
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result << work if work.length.nonzero?
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result.join("\n").gsub(/^/, " " * indent)
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end
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def min3(a, b, c) # :nodoc:
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if a < b && a < c
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a
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elsif b < c
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b
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else
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c
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end
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end
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# Returns a value representing the "cost" of transforming str1 into str2
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# Vendored version of DidYouMean::Levenshtein.distance from the ruby/did_you_mean gem @ 1.4.0
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# https://git.io/JJgZI
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def levenshtein_distance(str1, str2)
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n = str1.length
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m = str2.length
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return m if n.zero?
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return n if m.zero?
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d = (0..m).to_a
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x = nil
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# to avoid duplicating an enumerable object, create it outside of the loop
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str2_codepoints = str2.codepoints
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str1.each_codepoint.with_index(1) do |char1, i|
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j = 0
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while j < m
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cost = (char1 == str2_codepoints[j]) ? 0 : 1
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x = min3(
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d[j + 1] + 1, # insertion
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i + 1, # deletion
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d[j] + cost # substitution
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)
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d[j] = i
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i = x
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j += 1
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end
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d[m] = x
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end
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x
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end
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end
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