module Gem::BundlerVersionFinder

# File lib/rubygems/bundler_version_finder.rb, line 6
def self.bundler_version
  bcv = bundle_config_version
  return if bcv == "system"

  v = ENV["BUNDLER_VERSION"]
  v = nil if v&.empty?

  v ||= bundle_update_bundler_version
  return if v == true

  v ||= bcv unless bcv == "lockfile"

  v ||= lockfile_version
  return unless v

  # A config file is arbitrary YAML, so BUNDLE_VERSION can be a date, a
  # mapping, or anything else the parser makes of an unquoted scalar. None
  # of those name a version, and refusing to prioritize is better than
  # raising out of every command that resolves bundler by name.
  return unless Gem::Version.correct?(v)

  Gem::Version.new(v)
end

# File lib/rubygems/bundler_version_finder.rb, line 30
def self.prioritize!(specs)
  exact_match_index = specs.find_index {|spec| spec.version == bundler_version }
  return unless exact_match_index

  specs.unshift(specs.delete_at(exact_match_index))
end

# File lib/rubygems/bundler_version_finder.rb, line 84
def self.bundle_config_version
  Gem::BundlerSettings.env("version") || Gem::BundlerSettings.from_config_files("version")
end

# File lib/rubygems/bundler_version_finder.rb, line 37
def self.bundle_update_bundler_version
  return unless ["bundle", "bundler"].include? File.basename($0)
  return unless "update".start_with?(ARGV.first || " ")
  bundler_version = nil
  update_index = nil
  ARGV.each_with_index do |a, i|
    if update_index && update_index.succ == i && a =~ Gem::Version::ANCHORED_VERSION_PATTERN
      bundler_version = a
    end
    next unless a =~ /\A--bundler(?:[= ](#{Gem::Version::VERSION_PATTERN}))?\z/
    bundler_version = $1 || true
    update_index = i
  end
  bundler_version
end

# File lib/rubygems/bundler_version_finder.rb, line 89
def self.gemfile_path
  Gem::BundlerSettings.gemfile_path
end

# File lib/rubygems/bundler_version_finder.rb, line 62
def self.lockfile_contents
  gemfile = gemfile_path

  return unless gemfile

  lockfile = ENV["BUNDLE_LOCKFILE"]
  lockfile = nil if lockfile&.empty?

  lockfile ||= case gemfile
               when "gems.rb" then "gems.locked"
               else "#{gemfile}.lock"
  end

  return unless File.file?(lockfile)

  File.read(lockfile)
end

# File lib/rubygems/bundler_version_finder.rb, line 54
def self.lockfile_version
  return unless contents = lockfile_contents
  regexp = /\n\nBUNDLED WITH\n\s{2,}(#{Gem::Version::VERSION_PATTERN})\n/
  return unless contents =~ regexp
  $1
end