ruby/lib/did_you_mean/spell_checker.rb

47 строки
1.3 KiB
Ruby

# frozen-string-literal: true
require_relative "levenshtein"
require_relative "jaro_winkler"
module DidYouMean
class SpellChecker
def initialize(dictionary:)
@dictionary = dictionary
end
def correct(input)
normalized_input = normalize(input)
threshold = normalized_input.length > 3 ? 0.834 : 0.77
words = @dictionary.select { |word| JaroWinkler.distance(normalize(word), normalized_input) >= threshold }
words.reject! { |word| input.to_s == word.to_s }
words.sort_by! { |word| JaroWinkler.distance(word.to_s, normalized_input) }
words.reverse!
# Correct mistypes
threshold = (normalized_input.length * 0.25).ceil
corrections = words.select { |c| Levenshtein.distance(normalize(c), normalized_input) <= threshold }
# Correct misspells
if corrections.empty?
corrections = words.select do |word|
word = normalize(word)
length = normalized_input.length < word.length ? normalized_input.length : word.length
Levenshtein.distance(word, normalized_input) < length
end.first(1)
end
corrections
end
private
def normalize(str_or_symbol) #:nodoc:
str = str_or_symbol.to_s.downcase
str.tr!("@", "")
str
end
end
end