Decrease complexity of vendored_packages_without_version method

It was O(n^2) because it iterated over packages_with_versions multiple times. Now it is O(n) because it uses a set to track versioned packages and checks membership in constant time. Also do a single pass in the importmap lines to find unversioned packages.

Author: rafaelfranca

lib/importmap/npm.rb

@@ -139,17 +139,25 @@ def post_json(uri, body)
  end
 
  def vendored_packages_without_version(packages_with_versions)
+ versioned_packages = packages_with_versions.map(&:first).to_set
+
  importmap
  .lines
- .filter_map do |line|
- next line.match(/#{PIN_REGEX}to: ["']([^["']]*)["'].*/).captures if line.include?("to:")
- match = line.match(PIN_REGEX)
- [match.captures.first, "#{match.captures.first}.js"] if match
- end
- .filter_map do |package, filename|
- next if packages_with_versions.map(&:first).include?(package)
- path = File.join(@vendor_path, filename)
- [package, path] if File.exist?(path)
- end
+ .filter_map { |line| find_unversioned_vendored_package(line, versioned_packages) }
+ end
+
+ def find_unversioned_vendored_package(line, versioned_packages)
+ regexp = line.include?("to:")? /#{PIN_REGEX}to: ["']([^["']]*)["'].*/ : PIN_REGEX
+ match = line.match(regexp)
+
+ return unless match
+
+ package, filename = match.captures
+ filename ||= "#{package}.js"
+
+ return if versioned_packages.include?(package)
+
+ path = File.join(@vendor_path, filename)
+ [package, path] if File.exist?(path)
  end
 end