comparable.rb

# frozen_string_literal: true

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module Comparable
  def ==(other)
    return true if Primitive.equal?(self, other)

    return false if Truffle::ThreadOperations.detect_pair_recursion(self, other) do
      unless comp = (self <=> other)
        return false
      end

      return Comparable.compare_int(comp) == 0
    end
  end

  def >(other)
    unless comp = (self <=> other)
      raise ArgumentError, Truffle::ExceptionOperations.comparison_error_message(self, other)
    end

    Comparable.compare_int(comp) > 0
  end

  def >=(other)
    unless comp = (self <=> other)
      raise ArgumentError, Truffle::ExceptionOperations.comparison_error_message(self, other)
    end

    Comparable.compare_int(comp) >= 0
  end

  def <(other)
    unless comp = (self <=> other)
      raise ArgumentError, Truffle::ExceptionOperations.comparison_error_message(self, other)
    end

    Comparable.compare_int(comp) < 0
  end

  def <=(other)
    unless comp = (self <=> other)
      raise ArgumentError, Truffle::ExceptionOperations.comparison_error_message(self, other)
    end

    Comparable.compare_int(comp) <= 0
  end

  def between?(min, max)
    # This could be more elegant, but we need to use <= and => on self to match
    # MRI.
    return false if self < min
    return false if self > max
    true
  end

  def clamp(min, max = undefined)
    if Primitive.undefined?(max)
      range = min
      raise TypeError, "wrong argument type #{Primitive.class(range)} (expected Range)" unless Primitive.is_a?(range, Range)
      raise ArgumentError, 'cannot clamp with an exclusive range' if range.exclude_end?
      min, max = range.begin, range.end
    end

    comp = min <=> max
    raise ArgumentError, 'min argument must be smaller than max argument' if Primitive.nil?(comp) or comp > 0
    return min if self < min
    return max if self > max
    self
  end

  # A version of MRI's rb_cmpint (sort of)
  def self.compare_int(int)
    return int if Primitive.is_a?(int, Integer)

    return 1  if int > 0
    return -1 if int < 0
    0
  end
end