Class: OptimistXL::Parser

Inherits:
Object
  • Object
show all
Defined in:
lib/optimist_xl.rb

Overview

The commandline parser. In typical usage, the methods in this class will be handled internally by OptimistXL::options. In this case, only the #opt, #banner and #version, #depends, and #conflicts methods will typically be called.

If you want to instantiate this class yourself (for more complicated argument-parsing logic), call #parse to actually produce the output hash, and consider calling it from within OptimistXL::with_standard_exception_handling.

Direct Known Subclasses

SubcommandParser

Constant Summary collapse

DEFAULT_SETTINGS = 
{ exact_match: false,
  explicit_short_opts: false,
  suggestions: true
}

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(*a, &b) ⇒ Parser

Initializes the parser, and instance-evaluates any block given.



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# File 'lib/optimist_xl.rb', line 98

def initialize(*a, &b)
  @version = nil
  @leftovers = []
  @specs = {}
  @long = {}
  @short = {}
  @order = []
  @constraints = []
  @stop_words = []
  @stop_on_unknown = false
  @educate_on_error = false
  @synopsis = nil
  @usage = nil
  @subcommand_parsers = {}

  ## allow passing settings through Parser.new as an optional hash.
  ## but keep compatibility with non-hashy args, though.
  begin
    settings_hash = Hash[*a]
    @settings = DEFAULT_SETTINGS.merge(settings_hash)
    a=[] ## clear out args if using as settings-hash
  rescue ArgumentError
    @settings = DEFAULT_SETTINGS
  end

  # instance_eval(&b) if b # can't take arguments
  #cloaker(&b).bind(self).call(*a) if b
  self.instance_exec(*a, &b) if block_given?
end

Instance Attribute Details

#ignore_invalid_options ⇒ Object

A flag that determines whether or not to raise an error if the parser is passed one or more

options that were not registered ahead of time.  If 'true', then the parser will simply
ignore options that it does not recognize.



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# File 'lib/optimist_xl.rb', line 89

def ignore_invalid_options
  @ignore_invalid_options
end

#leftovers ⇒ Object (readonly)

The values from the commandline that were not interpreted by #parse.



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# File 'lib/optimist_xl.rb', line 80

def leftovers
  @leftovers
end

#specs ⇒ Object (readonly)

The complete configuration hashes for each option. (Mainly useful for testing.)



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# File 'lib/optimist_xl.rb', line 84

def specs
  @specs
end

Class Method Details

.register(lookup, klass) ⇒ Object

The Option subclasses are responsible for registering themselves using this function.



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# File 'lib/optimist_xl.rb', line 61

def self.register(lookup, klass)
  @registry[lookup.to_sym] = klass
end

.registry_getopttype(type) ⇒ Object

Gets the class from the registry. Can be given either a class-name, e.g. Integer, a string, e.g “integer”, or a symbol, e.g :integer

Raises:

  • (ArgumentError) 


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# File 'lib/optimist_xl.rb', line 67

def self.registry_getopttype(type)
  return nil unless type
  if type.respond_to?(:name)
    type = type.name
    lookup = type.downcase.to_sym
  else
    lookup = type.to_sym
  end
  raise ArgumentError, "Unsupported argument type '#{type}', registry lookup '#{lookup}'" unless @registry.has_key?(lookup)
  return @registry[lookup].new
end

Instance Method Details

Adds text to the help display. Can be interspersed with calls to #opt to build a multi-section help page.



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# File 'lib/optimist_xl.rb', line 219

def banner(s)
  @order << [:text, s]
end

#conflicts(*syms) ⇒ Object

Marks two (or more!) options as conflicting.



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# File 'lib/optimist_xl.rb', line 233

def conflicts(*syms)
  syms.each { |sym| raise ArgumentError, "unknown option '#{sym}'" unless @specs[sym] }
  @constraints << [:conflicts, syms]
end

#default_banner ⇒ Object

Create default text banner in a string so we can override it in the SubcommandParser class.



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# File 'lib/optimist_xl.rb', line 517

def default_banner
  command_name = File.basename($0).gsub(/\.[^.]+$/, '')
  bannertext = ''
  bannertext << "Usage: #{command_name} #{@usage}\n" if @usage
  bannertext << "#{@synopsis}\n" if @synopsis
  bannertext << "\n" if @usage || @synopsis
  bannertext << "#{@version}\n" if @version
  unless subcommands.empty?
    bannertext << "\n" if @version   
    bannertext << "Commands:\n"
    @subcommand_parsers.each_value do |scmd|
      bannertext << sprintf("  %-20s %s\n", scmd.name, scmd.desc)
    end
    bannertext << "\n"   
  end
  bannertext << "Options:\n"
  return bannertext
end

#depends(*syms) ⇒ Object

Marks two (or more!) options as requiring each other. Only handles undirected (i.e., mutual) dependencies. Directed dependencies are better modeled with OptimistXL::die.



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# File 'lib/optimist_xl.rb', line 227

def depends(*syms)
  syms.each { |sym| raise ArgumentError, "unknown option '#{sym}'" unless @specs[sym] }
  @constraints << [:depends, syms]
end

#die(arg, msg = nil, error_code = nil) ⇒ Object

The per-parser version of OptimistXL::die (see that for documentation).



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# File 'lib/optimist_xl.rb', line 604

def die(arg, msg = nil, error_code = nil)
  msg, error_code = nil, msg if msg.kind_of?(Integer)
  if msg
    $stderr.puts "Error: argument --#{@specs[arg].long} #{msg}."
  else
    $stderr.puts "Error: #{arg}."
  end
  if @educate_on_error
    $stderr.puts
    educate $stderr
  else
    $stderr.puts "Try --help for help."
  end
  exit(error_code || -1)
end

#educate(stream = $stdout) ⇒ Object

Print the help message to stream.



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# File 'lib/optimist_xl.rb', line 538

def educate(stream = $stdout)
  width # hack: calculate it now; otherwise we have to be careful not to
        # call this unless the cursor's at the beginning of a line.

  left = {}
  @specs.each { |name, spec| left[name] = spec.educate }

  leftcol_width = left.values.map(&:length).max || 0
  rightcol_start = leftcol_width + 6 # spaces

  # print a default banner here if there is no text/banner
  unless @order.size > 0 && @order.first.first == :text
    stream.puts default_banner()
  end

  @order.each do |what, opt|
    if what == :text
      # print text/banner here
      stream.puts wrap(opt)
      next
    end

    spec = @specs[opt]
    stream.printf "  %-#{leftcol_width}s    ", left[opt]
    desc = spec.full_description

    stream.puts wrap(desc, :width => width - rightcol_start - 1, :prefix => rightcol_start)
  end
end

#educate_on_error ⇒ Object

Instead of displaying “Try –help for help.” on an error display the usage (via educate)



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# File 'lib/optimist_xl.rb', line 261

def educate_on_error
  @educate_on_error = true
end

#opt(name, desc = "", opts = {}, &b) ⇒ Object

Define an option. name is the option name, a unique identifier for the option that you will use internally, which should be a symbol or a string. desc is a string description which will be displayed in help messages.

Takes the following optional arguments:

:long

Specify the long form of the argument, i.e. the form with two dashes. If unspecified, will be automatically derived based on the argument name by turning the name option into a string, and replacing any _’s by -‘s.

:short

Specify the short form of the argument, i.e. the form with one dash. If unspecified, will be automatically derived from name. Use :none: to not have a short value.

:type

Require that the argument take a parameter or parameters of type type. For a single parameter, the value can be a member of SINGLE_ARG_TYPES, or a corresponding Ruby class (e.g. Integer for :int). For multiple-argument parameters, the value can be any member of MULTI_ARG_TYPES constant. If unset, the default argument type is :flag, meaning that the argument does not take a parameter. The specification of :type is not necessary if a :default is given.

:default

Set the default value for an argument. Without a default value, the hash returned by #parse (and thus OptimistXL::options) will have a nil value for this key unless the argument is given on the commandline. The argument type is derived automatically from the class of the default value given, so specifying a :type is not necessary if a :default is given. (But see below for an important caveat when :multi: is specified too.) If the argument is a flag, and the default is set to true, then if it is specified on the the commandline the value will be false.

:required

If set to true, the argument must be provided on the commandline.

:multi

If set to true, allows multiple occurrences of the option on the commandline. Otherwise, only a single instance of the option is allowed. (Note that this is different from taking multiple parameters. See below.)

Note that there are two types of argument multiplicity: an argument can take multiple values, e.g. “–arg 1 2 3”. An argument can also be allowed to occur multiple times, e.g. “–arg 1 –arg 2”.

Arguments that take multiple values should have a :type parameter drawn from MULTI_ARG_TYPES (e.g. :strings), or a :default: value of an array of the correct type (e.g. [String]). The value of this argument will be an array of the parameters on the commandline.

Arguments that can occur multiple times should be marked with :multi => true. The value of this argument will also be an array. In contrast with regular non-multi options, if not specified on the commandline, the default value will be [], not nil.

These two attributes can be combined (e.g. :type => :strings, :multi => true), in which case the value of the argument will be an array of arrays.

There’s one ambiguous case to be aware of: when :multi: is true and a :default is set to an array (of something), it’s ambiguous whether this is a multi-value argument as well as a multi-occurrence argument. In thise case, OptimistXL assumes that it’s not a multi-value argument. If you want a multi-value, multi-occurrence argument with a default value, you must specify :type as well.

Raises:

  • (ArgumentError) 


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# File 'lib/optimist_xl.rb', line 168

def opt(name, desc = "", opts = {}, &b)
  opts[:callback] ||= b if block_given?
  opts[:desc] ||= desc

  o = Option.create(name, desc, opts)

  raise ArgumentError, "you already have an argument named '#{name}'" if @specs.member? o.name
  o.long.names.each do |lng|
    raise ArgumentError, "long option name #{lng.inspect} is already taken; please specify a (different) :long/:alt" if @long[lng]
    @long[lng] = o.name
  end

  raise ArgumentError, "permitted values for option #{o.long.long.inspect} must be either nil, Range, Regexp or an Array;" unless o.permitted_type_valid?

  o.short.chars.each do |short|
    raise ArgumentError, "short option name #{short.inspect} is already taken; please specify a (different) :short" if @short[short]
    @short[short] = o.name
  end

  @specs[o.name] = o
  @order << [:opt, o.name]
end

#parse(cmdline = ARGV) ⇒ Object

Parses the commandline. Typically called by OptimistXL::options, but you can call it directly if you need more control.

throws CommandlineError, HelpNeeded, and VersionNeeded exceptions.



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# File 'lib/optimist_xl.rb', line 326

def parse(cmdline = ARGV)
  if subcommands.empty?
    parse_base(cmdline)
  else
    # set state for subcommand-parse
    @stop_words += subcommands
    @stop_on_unknown = true
    # parse global options
    global_result = parse_base(cmdline)
    # grab subcommand
    cmd = cmdline.shift
    raise CommandlineError.new('no subcommand provided') unless cmd
    # parse subcommand options
    subcmd_parser = @subcommand_parsers[cmd.to_sym]
    raise CommandlineError.new("unknown subcommand '#{cmd}'") unless subcmd_parser
    subcmd_result = subcmd_parser.parse_base(cmdline)
    SubcommandResult.new(subcommand: cmd,
                         global_options: global_result,
                         subcommand_options: subcmd_result,
                         leftovers: subcmd_parser.leftovers)
  end
end

#parse_base(cmdline = ARGV) ⇒ Object

Raises:



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# File 'lib/optimist_xl.rb', line 349

def parse_base(cmdline = ARGV)
  vals = {}
  required = {}

  # create default version/help options if not already defined
  opt :version, "Print version and exit" if @version && ! (@specs[:version] || @long["version"])
  opt :help, "Show this message" unless @specs[:help] || @long["help"]

  @specs.each do |sym, opts|
    required[sym] = true if opts.required?
    vals[sym] = opts.default
    vals[sym] = [] if opts.multi && !opts.default # multi arguments default to [], not nil
  end

  resolve_default_short_options! unless @settings[:explicit_short_opts]

  ## resolve symbols
  given_args = {}
  @leftovers = each_arg cmdline do |original_arg, params|
    ## handle --no- forms
    arg, negative_given = if original_arg =~ /^--no-([^-]\S*)$/
      ["--#{$1}", true]
    else
      [original_arg, false]
    end

    sym = case arg
      when /^-([^-])$/      then @short[$1]
      when /^--([^-]\S*)$/  then @long[$1] || @long["no-#{$1}"]
      else                       raise CommandlineError, "invalid argument syntax: '#{arg}'"
    end

    if arg =~ /--no-/ # explicitly invalidate --no-no- arguments
      sym = nil 
    elsif !sym && !@settings[:exact_match] && arg.match(/^--(\S*)$/)
      # If sym is not already found in the short/long lookup then 
      # support inexact matching of long-arguments like perl's Getopt::Long
      sym = perform_inexact_match(arg, $1)
    end
    
    next nil if ignore_invalid_options && !sym
    
    handle_unknown_argument(arg, @long.keys, @settings[:suggestions]) unless sym

    if given_args.include?(sym) && !@specs[sym].multi?
      raise CommandlineError, "option '#{arg}' specified multiple times"
    end

    given_args[sym] ||= {}
    given_args[sym][:arg] = arg
    given_args[sym][:negative_given] = negative_given
    given_args[sym][:params] ||= []

    # The block returns the number of parameters taken.
    num_params_taken = 0

    #DEBUG# puts "\nparams:#{params} npt:#{num_params_taken},ps:#{params.size}"

    #if params.size > 0
    #  if @specs[sym].min_args == 1 && @specs[sym].max_args == 1
    #    given_args[sym][:params] << params[0, 1]  # take the first parameter
    #    num_params_taken = 1
    #  elsif @specs[sym].max_args > 1
    #    given_args[sym][:params] << params        # take all the parameters
    #    num_params_taken = params.size
    #  end
    #end

    if params.size == 0
      if @specs[sym].min_args == 0
        given_args[sym][:params] << [ @specs[sym].default || true]
      end
    elsif params.size > 0
      if params.size >= @specs[sym].max_args
        # take smaller of the two sizes to determine how many parameters to take
        num_params_taken = [params.size, @specs[sym].max_args].min
        given_args[sym][:params] << params[0, num_params_taken]
      else
        # take all the parameters
        given_args[sym][:params] << params        
        num_params_taken = params.size
      end
    end
    

    num_params_taken
  end

  ## check for version and help args, and raise if set.
  ## HelpNeeded should pass the parser object so we know how to educate
  ## if we are in a global-command or subcommand
  raise VersionNeeded if given_args.include? :version
  raise HelpNeeded.new(nil, parser: self) if given_args.include? :help

  ## check constraint satisfaction
  @constraints.each do |type, syms|
    constraint_sym = syms.find { |sym| given_args[sym] }
    next unless constraint_sym

    case type
    when :depends
      syms.each { |sym| raise CommandlineError, "--#{@specs[constraint_sym].long} requires --#{@specs[sym].long}" unless given_args.include? sym }
    when :conflicts
      syms.each { |sym| raise CommandlineError, "--#{@specs[constraint_sym].long} conflicts with --#{@specs[sym].long}" if given_args.include?(sym) && (sym != constraint_sym) }
    end
  end

  required.each do |sym, _val|
    raise CommandlineError, "option --#{@specs[sym].long} must be specified" unless given_args.include? sym
  end

  ## parse parameters
  given_args.each do |sym, given_data|
    arg, params, negative_given = given_data.values_at :arg, :params, :negative_given

    opts = @specs[sym]

    if params.size < opts.min_args
      raise CommandlineError, "option '#{arg}' needs a parameter" unless opts.default
      params << (opts.array_default? ? opts.default.clone : [opts.default])
    end

    if params.first && opts.permitted
      params.first.each do |val|
        opts.validate_permitted(arg, val)
      end
    end

    vals["#{sym}_given".intern] = true # mark argument as specified on the commandline

    vals[sym] = opts.parse(params, negative_given)

    if opts.min_args==0 && opts.max_args==1
      if opts.multi?
        vals[sym] = vals[sym].map { |p| p[0] }
      else
        vals[sym] = vals[sym][0][0]
      end
    elsif opts.min_args==1 && opts.max_args==1
      if opts.multi?        # multiple options, each with a single parameter
        vals[sym] = vals[sym].map { |p| p[0] }
      else                  # single parameter
        vals[sym] = vals[sym][0][0]
      end
    elsif opts.max_args>1 && !opts.multi?
      vals[sym] = vals[sym][0]  # single option, with multiple parameters
    end
    # else: multiple options, with multiple parameters

    opts.callback.call(vals[sym]) if opts.callback
  end

  ## modify input in place with only those
  ## arguments we didn't process
  cmdline.clear
  @leftovers.each { |l| cmdline << l }

  ## allow openstruct-style accessors
  class << vals
    def method_missing(m, *_args)
      self[m] || self[m.to_s]
    end
  end
  vals
end

#stop_on(*words) ⇒ Object

Defines a set of words which cause parsing to terminate when encountered, such that any options to the left of the word are parsed as usual, and options to the right of the word are left intact.

A typical use case would be for subcommand support, where these would be set to the list of subcommands. A subsequent OptimistXL invocation would then be used to parse subcommand options, after shifting the subcommand off of ARGV.



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# File 'lib/optimist_xl.rb', line 247

def stop_on(*words)
  @stop_words = [*words].flatten
end

#stop_on_unknown ⇒ Object

Similar to #stop_on, but stops on any unknown word when encountered (unless it is a parameter for an argument). This is useful for cases where you don’t know the set of subcommands ahead of time, i.e., without first parsing the global options.



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# File 'lib/optimist_xl.rb', line 255

def stop_on_unknown
  @stop_on_unknown = true
end

#subcmd(name, desc = nil, args = {}, &b) ⇒ Object 



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# File 'lib/optimist_xl.rb', line 191

def subcmd(name, desc=nil, args = {}, &b)
  sc = SubcommandParser.new(name, desc, *args, &b)
  @subcommand_parsers[name.to_sym] = sc
  return sc
end

#subcommands ⇒ Object

Provide a list of given subcommands. List will be empty if subcmd was never given.



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# File 'lib/optimist_xl.rb', line 318

def subcommands
  @subcommand_parsers.keys
end

#synopsis(s = nil) ⇒ Object

Adds a synopsis (command summary description) right below the usage line, or as the first line if usage isn’t specified.



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# File 'lib/optimist_xl.rb', line 213

def synopsis(s = nil)
  s ? @synopsis = s : @synopsis
end

#usage(s = nil) ⇒ Object

Sets the usage string. If set the message will be printed as the first line in the help (educate) output and ending in two new lines.



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# File 'lib/optimist_xl.rb', line 207

def usage(s = nil)
  s ? @usage = s : @usage
end

#version(s = nil) ⇒ Object

Sets the version string. If set, the user can request the version on the commandline. Should probably be of the form “<program name> <version number>”.



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# File 'lib/optimist_xl.rb', line 200

def version(s = nil)
  s ? @version = s : @version
end

#width ⇒ Object

:nodoc:



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# File 'lib/optimist_xl.rb', line 568

def width #:nodoc:
  @width ||= if $stdout.tty?
    begin
      require 'io/console'
      w = IO.console.winsize.last
      w.to_i > 0 ? w : 80
    rescue LoadError, NoMethodError, Errno::ENOTTY, Errno::EBADF, Errno::EINVAL
      legacy_width
    end
  else
    80
  end
end

#wrap(str, opts = {}) ⇒ Object

:nodoc:



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# File 'lib/optimist_xl.rb', line 590

def wrap(str, opts = {}) # :nodoc:
  if str == ""
    [""]
  else
    inner = false
    str.split("\n").map do |s|
      line = wrap_line s, opts.merge(:inner => inner)
      inner = true
      line
    end.flatten
  end
end