class Pry::Command

The super-class of all commands, new commands should be created by calling {Pry::CommandSet#command} which creates a BlockCommand or {Pry::CommandSet#create_command} which creates a ClassCommand. Please don't use this class directly.

Constants

VOID_VALUE

represents a void return value for a command

Attributes

block[W]
command_options[W]
description[W]
match[W]
options[RW]
_pry_[RW]
arg_string[RW]
captures[RW]
command_block[RW]

The block we pass into a command so long as `:takes_block` is not equal to `false` @example

my-command | do
  puts "block content"
end
command_set[RW]
context[RW]
eval_string[RW]
output[RW]

Properties of one execution of a command (passed by {Pry#run_command} as a hash of context and expanded in `#initialize`

target[RW]

Public Class Methods

new(context={}) click to toggle source

Instantiate a command, in preparation for calling it. @param [Hash] context The runtime context to use with this command.

# File lib/pry/command.rb, line 266
def initialize(context={})
  self.context      = context
  self.target       = context[:target]
  self.output       = context[:output]
  self.eval_string  = context[:eval_string]
  self.command_set  = context[:command_set]
  self._pry_        = context[:pry_instance]
end

Public Instance Methods

banner(arg=nil) click to toggle source

Define or get the command's banner

block() click to toggle source
# File lib/pry/command.rb, line 58
def block
  @block || instance_method(:process)
end
call_safely(*args) click to toggle source

Run the command with the given `args`.

This is a public wrapper around `#call` which ensures all preconditions are met.

@param [Array<String>] args The arguments to pass to this command. @return [Object] The return value of the `#call` method, or

{Command::VOID_VALUE}.
# File lib/pry/command.rb, line 412
def call_safely(*args)
  unless dependencies_met?
    gems_needed = Array(command_options[:requires_gem])
    gems_not_installed = gems_needed.select { |g| !Rubygem.installed?(g) }
    output.puts "\nThe command '#{command_name}' is #{text.bold("unavailable")} because it requires the following gems to be installed: #{(gems_not_installed.join(", "))}"
    output.puts "-"
    output.puts "Type `install-command #{command_name}` to install the required gems and activate this command."
    return void
  end

  if command_options[:argument_required] && args.empty?
    raise CommandError, "The command '#{command_name}' requires an argument."
  end

  ret = call_with_hooks(*args)
  command_options[:keep_retval] ? ret : void
end
check_for_command_collision(command_match, arg_string) click to toggle source

Display a warning if a command collides with a local/method in the current scope.

# File lib/pry/command.rb, line 305
def check_for_command_collision(command_match, arg_string)
  collision_type = target.eval("defined?(#{command_match})")
  collision_type ||= 'local-variable' if arg_string.match(%r{\A\s*[-+*/%&|^]*=})

  if collision_type
    output.puts "#{text.bold('WARNING:')} Calling Pry command '#{command_match}'," +
                                                      "which conflicts with a #{collision_type}.\n\n"
  end
rescue Pry::RescuableException
end
command_name() click to toggle source
# File lib/pry/command.rb, line 105
def command_name; self.class.command_name; end
command_options(arg=nil) click to toggle source

Define or get the command's options

# File lib/pry/command.rb, line 43
def command_options(arg=nil)
  @command_options ||= default_options(match)
  @command_options.merge!(arg) if arg
  @command_options
end
command_regex() click to toggle source
# File lib/pry/command.rb, line 177
def command_regex
  pr = defined?(Pry.config.command_prefix) ? Pry.config.command_prefix : ""
  prefix = convert_to_regex(pr)
  prefix = "(?:#{prefix})?" unless options[:use_prefix]

  /^#{prefix}#{convert_to_regex(match)}(?!\S)/
end
commands() click to toggle source
# File lib/pry/command.rb, line 249
def commands
  command_set.commands
end
complete(search) click to toggle source

Generate completions for this command

@param [String] search The line typed so far @return [Array<String>] Completion words

# File lib/pry/command.rb, line 441
def complete(search); Bond::DefaultMission.completions; end
convert_to_regex(obj) click to toggle source
# File lib/pry/command.rb, line 185
def convert_to_regex(obj)
  case obj
  when String
    Regexp.escape(obj)
  else
    obj
  end
end
default_options(match) click to toggle source
# File lib/pry/command.rb, line 85
def default_options(match)
  {
    :requires_gem      => [],
    :keep_retval       => false,
    :argument_required => false,
    :interpolate       => true,
    :shellwords        => true,
    :listing           => (String === match ? match : match.inspect),
    :use_prefix        => true,
    :takes_block       => false
  }
end
dependencies_met?() click to toggle source

Are all the gems required to use this command installed?

@return Boolean

# File lib/pry/command.rb, line 433
def dependencies_met?
  @dependencies_met ||= command_dependencies_met?(command_options)
end
description(arg=nil) click to toggle source

Define or get the command's description

# File lib/pry/command.rb, line 37
def description(arg=nil)
  @description = arg if arg
  @description
end
doc() click to toggle source
# File lib/pry/command.rb, line 67
def doc
  new.help
end
group(name=nil) click to toggle source

The group in which the command should be displayed in “help” output. This is usually auto-generated from directory naming, but it can be manually overridden if necessary.

# File lib/pry/command.rb, line 197
def group(name=nil)
  @group ||= if name
               name
             else
               case Pry::Method(block).source_file
               when %r{/pry/.*_commands/(.*).rb}
                 $1.capitalize.gsub(/_/, " ")
               when %r{(pry-\w+)-([\d\.]+([\w\d\.]+)?)}
                 name, version = $1, $2
                 "#{name.to_s} (v#{version.to_s})"
               when /pryrc/
                 "~/.pryrc"
               else
                 "(other)"
               end
             end
end
hooks() click to toggle source

Store hooks to be run before or after the command body. @see {Pry::CommandSet#before_command} @see {Pry::CommandSet#after_command}

# File lib/pry/command.rb, line 173
def hooks
  @hooks ||= {:before => [], :after => []}
end
inspect() click to toggle source
# File lib/pry/command.rb, line 114
def inspect
  name
end
interpolate_string(str) click to toggle source

Revaluate the string (str) and perform interpolation. @param [String] str The string to reevaluate with interpolation.

@return [String] The reevaluated string with interpolations

applied (if any).
# File lib/pry/command.rb, line 294
def interpolate_string(str)
  dumped_str = str.dump
  if dumped_str.gsub!(/\\#\{/, '#{')
    target.eval(dumped_str)
  else
    str
  end
end
match(arg=nil) click to toggle source
# File lib/pry/command.rb, line 27
def match(arg=nil)
  if arg
    @command_options ||= default_options(arg)
    @command_options[:listing] = arg.is_a?(String) ? arg : arg.inspect
    @match = arg
  end
  @match
end
match_score(val) click to toggle source

How well does this command match the given line?

Higher scores are better because they imply that this command matches the line more closely.

The score is calculated by taking the number of characters at the start of the string that are used only to identify the command, not as part of the arguments.

@example

/\.(.*)/.match_score(".foo") #=> 1
/\.*(.*)/.match_score("...foo") #=> 3
'hi'.match_score("hi there") #=> 2

@param [String] val A line input at the REPL @return [Fixnum]

# File lib/pry/command.rb, line 162
def match_score(val)
  if command_regex =~ val
    Regexp.last_match.size > 1 ? Regexp.last_match.begin(1) : Regexp.last_match.end(0)
  else
    -1
  end
end
matches?(val) click to toggle source

Should this command be called for the given line? @param [String] val A line input at the REPL @return [Boolean]

# File lib/pry/command.rb, line 142
def matches?(val)
  command_regex =~ val
end
name() click to toggle source

Make those properties accessible to instances

# File lib/pry/command.rb, line 100
def name; self.class.name; end
process_line(line) click to toggle source

Process a line that #matches? this command. @param [String] line The line to process @return [Object, Command::VOID_VALUE]

# File lib/pry/command.rb, line 360
def process_line(line)
  command_match, arg_string, captures, args = tokenize(line)

  check_for_command_collision(command_match, arg_string) if Pry.config.collision_warning

  self.arg_string = arg_string
  self.captures = captures

  call_safely(*(captures + args))
end
run(command_string, *args) click to toggle source

Run a command from another command. @param [String] command_string The string that invokes the command @param [Array] args Further arguments to pass to the command @example

run "show-input"

@example

run ".ls"

@example

run "amend-line",  "5", 'puts "hello world"'
# File lib/pry/command.rb, line 244
def run(command_string, *args)
  complete_string = "#{command_string} #{args.join(" ")}".rstrip
  command_set.process_line(complete_string, context)
end
source() click to toggle source
# File lib/pry/command.rb, line 62
def source
  file, line = block.source_location
  strip_leading_whitespace(Pry::Code.from_file(file).expression_at(line))
end
source_file() click to toggle source
# File lib/pry/command.rb, line 75
def source_file
  Array(block.source_location).first
end
source_line() click to toggle source
# File lib/pry/command.rb, line 80
def source_line
  Array(block.source_location).last
end
source_location() click to toggle source
# File lib/pry/command.rb, line 71
def source_location
  block.source_location
end
state() click to toggle source

@return [Hash] Pry commands can store arbitrary state

here. This state persists between subsequent command invocations.
All state saved here is unique to the command, it does not
need to be namespaced.

@example

state.my_state = "my state"  # this will not conflict with any
                             # `state.my_state` used in another command.
# File lib/pry/command.rb, line 285
def state
  _pry_.command_state[match] ||= OpenStruct.new
end
subclass(match, description, options, helpers, &block) click to toggle source

Create a new command with the given properties. @param [String, Regex] match The thing that triggers this command @param [String] description The description to appear in `help` @param [Hash] options Behavioral options (see {Pry::CommandSet#command}) @param [Module] helpers A module of helper functions to be included. @yield optional, used for BlockCommands @return [Class] (a subclass of {Pry::Command})

# File lib/pry/command.rb, line 129
def subclass(match, description, options, helpers, &block)
  klass = Class.new(self)
  klass.send(:include, helpers)
  klass.match = match
  klass.description = description
  klass.command_options = options
  klass.block = block
  klass
end
target_self() click to toggle source

@return [Object] The value of `self` inside the `target` binding.

# File lib/pry/command.rb, line 276
def target_self; target.eval('self'); end
text() click to toggle source
# File lib/pry/command.rb, line 253
def text
  Pry::Helpers::Text
end
tokenize(val) click to toggle source

Extract necessary information from a line that #matches? this command.

Returns an array of four elements:

“`

[String] the portion of the line that matched with the Command match
[String] a string of all the arguments (i.e. everything but the match)
[Array]  the captures caught by the command_regex
[Array]  the arguments obtained by splitting the arg_string

“`

@param [String] val The line of input @return [Array]

# File lib/pry/command.rb, line 330
def tokenize(val)
  val.replace(interpolate_string(val)) if command_options[:interpolate]

  self.class.command_regex =~ val

  # please call Command.matches? before Command#call_safely
  raise CommandError, "fatal: called a command which didn't match?!" unless Regexp.last_match
  captures = Regexp.last_match.captures
  pos = Regexp.last_match.end(0)

  arg_string = val[pos..-1]

  # remove the one leading space if it exists
  arg_string.slice!(0) if arg_string.start_with?(" ")

  # process and pass a block if one is found
  pass_block(arg_string) if command_options[:takes_block]

  if arg_string
    args = command_options[:shellwords] ? Shellwords.shellwords(arg_string) : arg_string.split(" ")
  else
    args = []
  end

  [val[0..pos].rstrip, arg_string, captures, args]
end
void() click to toggle source
# File lib/pry/command.rb, line 257
def void
  VOID_VALUE
end

Private Instance Methods

call_with_hooks(*args) click to toggle source

Run the `#call` method and all the registered hooks. @param [Array<String>] args The arguments to `#call` @return [Object] The return value from `#call`

# File lib/pry/command.rb, line 448
def call_with_hooks(*args)
  self.class.hooks[:before].each do |block|
    instance_exec(*args, &block)
  end

  ret = call(*args)

  self.class.hooks[:after].each do |block|
    ret = instance_exec(*args, &block)
  end

  ret
end
correct_arg_arity(arity, args) click to toggle source

Fix the number of arguments we pass to a block to avoid arity warnings. @param [Fixnum] arity The arity of the block @param [Array] args The arguments to pass @return [Array] A (possibly shorter) array of the arguments to pass

# File lib/pry/command.rb, line 466
def correct_arg_arity(arity, args)
  case
  when arity < 0
    args
  when arity == 0
    []
  when arity > 0
    args.values_at(*(0..(arity - 1)).to_a)
  end
end
pass_block(arg_string) click to toggle source

Pass a block argument to a command. @param [String] #arg_string The arguments (as a string) passed to the command.

We inspect these for a '| do' or a '| {' and if we find it we use it
to start a block input sequence. Once we have a complete
block, we save it to an accessor that can be retrieved from the command context.
Note that if we find the '| do' or '| {' we delete this and the
elements following it from `arg_string`.
# File lib/pry/command.rb, line 378
def pass_block(arg_string)
  # Workaround for weird JRuby bug where rindex in this case can return nil
  # even when there's a match.
  arg_string.scan(/\| *(?:do|\{)/)
  block_index = $~ && $~.offset(0)[0]

  return if !block_index

  block_init_string = arg_string.slice!(block_index..-1)[1..-1]
  prime_string = "proc #{block_init_string}\n"

  if !Pry::Code.complete_expression?(prime_string)
    block_string = _pry_.r(target, prime_string)
  else
    block_string = prime_string
  end

  begin
    self.command_block = target.eval(block_string)
  rescue Pry::RescuableException
    raise CommandError, "Incomplete block definition."
  end
end