Gem::SpecFetcher#search_for_dependency

# File tmp/rubies/ruby-4.1.0-preview1/lib/rubygems/spec_fetcher.rb, line 89
def search_for_dependency(dependency, matching_platform = true, type: nil)
  found = {}

  rejected_specs = {}

  specs_type = type || dependency.identity
  list, errors = available_specs(specs_type)

  list.each do |source, specs|
    if dependency.name.is_a?(String) && specs.respond_to?(:bsearch)
      start_index = (0...specs.length).bsearch {|i| specs[i].name >= dependency.name }
      end_index   = (0...specs.length).bsearch {|i| specs[i].name > dependency.name }
      specs = specs[start_index...end_index] if start_index && end_index
    end

    specs = specs.select {|tup| dependency.match?(tup) }
    specs = decode_source_content_addressable_tuples(source, specs, latest: specs_type == :latest)

    found[source] = specs.select do |tup|
      if matching_platform && !Gem::Platform.match_gem?(tup.platform, tup.name)
        pm = (
          rejected_specs[dependency] ||= \
            Gem::PlatformMismatch.new(tup.name, tup.version))
        pm.add_platform tup.platform
        false
      elsif matching_platform && !ruby_abi_match?(tup)
        false
      else
        true
      end
    end
  end

  errors += rejected_specs.values

  tuples = []

  found.each do |source, specs|
    specs.each do |s|
      tuples << [s, source]
    end
  end

  tuples = tuples.sort_by {|x| x[0].version }

  [tuples, errors]
end