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30990006a9
This reduces chances of errors where consumers of strings mutate inputs and reduces memory usage of the app. Test suite passes now, but there may be some stuff left, so we will run a few sites on a branch prior to merging
38 lines
860 B
Ruby
38 lines
860 B
Ruby
# frozen_string_literal: true
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# Modified version of: https://github.com/steventen/base62-rb
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module Base62
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KEYS ||= "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ".freeze
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KEYS_HASH ||= KEYS.each_char.with_index.to_h
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BASE ||= KEYS.length
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# Encodes base10 (decimal) number to base62 string.
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def self.encode(num)
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return "0" if num == 0
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return nil if num < 0
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str = ""
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while num > 0
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# prepend base62 charaters
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str = KEYS[num % BASE] + str
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num = num / BASE
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end
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str
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end
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# Decodes base62 string to a base10 (decimal) number.
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def self.decode(str)
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num = 0
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i = 0
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len = str.length - 1
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# while loop is faster than each_char or other 'idiomatic' way
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while i < str.length
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pow = BASE**(len - i)
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num += KEYS_HASH[str[i]] * pow
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i += 1
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end
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num
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end
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end
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