class Gem::Commands::SpecificationCommand - Documentation for Ruby 3.4
Description: Documentation for the Gem::Commands::SpecificationCommand class
Keywords: ruby,class,Gem::Commands::SpecificationCommand

# class Gem::Commands::SpecificationCommand

### Public Class Methods

new ()
Source

    # File lib/rubygems/commands/specification_command.rb, line 12
    def initialize
      Gem.load_yaml

      super "specification", "Display gem specification (in yaml)",
            domain: :local, version: Gem::Requirement.default,
            format: :yaml

      add_version_option("examine")
      add_platform_option
      add_prerelease_option

      add_option("--all", "Output specifications for all versions of",
                 "the gem") do |_value, options|
        options[:all] = true
      end

      add_option("--ruby", "Output ruby format") do |_value, options|
        options[:format] = :ruby
      end

      add_option("--yaml", "Output YAML format") do |_value, options|
        options[:format] = :yaml
      end

      add_option("--marshal", "Output Marshal format") do |_value, options|
        options[:format] = :marshal
      end

      add_local_remote_options
    end

Calls superclass method `Gem::Command::new`

### Public Instance Methods

execute ()
Source

    # File lib/rubygems/commands/specification_command.rb, line 74
    def execute
      specs = []
      gem = options[:args].shift

      unless gem
        raise Gem::CommandLineError,
              "Please specify a gem name or file on the command line"
      end

      case v = options[:version]
      when String
        req = Gem::Requirement.create v
      when Gem::Requirement
        req = v
      else
        raise Gem::CommandLineError, "Unsupported version type: '#{v}'"
      end

      if !req.none? && options[:all]
        alert_error "Specify --all or -v, not both"
        terminate_interaction 1
      end

      if options[:all]
        dep = Gem::Dependency.new gem
      else
        dep = Gem::Dependency.new gem, req
      end

      field = get_one_optional_argument

      raise Gem::CommandLineError, "--ruby and FIELD are mutually exclusive" if
        field && options[:format] == :ruby

      if local?
        if File.exist? gem
          begin
            specs << Gem::Package.new(gem).spec
          rescue StandardError
            nil
          end
        end

        if specs.empty?
          specs.push(*dep.matching_specs)
        end
      end

      if remote?
        dep.prerelease = options[:prerelease]
        found, _ = Gem::SpecFetcher.fetcher.spec_for_dependency dep

        specs.push(*found.map {|spec,| spec })
      end

      if specs.empty?
        alert_error "No gem matching '#{dep}' found"
        terminate_interaction 1
      end

      platform = get_platform_from_requirements(options)

      if platform
        specs = specs.select {|s| s.platform.to_s == platform }
      end

      unless options[:all]
        specs = [specs.max_by(&:version)]
      end

      specs.each do |s|
        s = s.send field if field

        say case options[:format]
            when :ruby then s.to_ruby
            when :marshal then Marshal.dump s
            else s.to_yaml
        end

        say "\n"
      end
    end