class Guard::PluginUtil

This class contains useful methods to:

Constants

ERROR_NO_GUARD_OR_CLASS
INFO_ADDED_GUARD_TO_GUARDFILE

Attributes

name[RW]

Public Class Methods

_gem_valid?(gem) click to toggle source
# File lib/guard/plugin_util.rb, line 182
def _gem_valid?(gem)
  return false if gem.name == "guard-compat"
  return true if gem.name =~ /^guard-/
  full_path = gem.full_gem_path
  file = File.join(full_path, "lib", "guard", "#{gem.name}.rb")
  File.exist?(file)
end
new(name) click to toggle source

Initializes a new ‘Guard::PluginUtil` object.

@param [String] name the name of the Guard plugin

# File lib/guard/plugin_util.rb, line 36
def initialize(name)
  @name = name.to_s.sub(/^guard-/, "")
end
plugin_names() click to toggle source

Returns a list of Guard plugin Gem names installed locally.

@return [Array<String>] a list of Guard plugin gem names

# File lib/guard/plugin_util.rb, line 24
def self.plugin_names
  valid = Gem::Specification.find_all.select do |gem|
    _gem_valid?(gem)
  end

  valid.map { |x| x.name.sub(/^guard-/, "") }.uniq
end

Public Instance Methods

add_to_guardfile() click to toggle source

Adds a plugin’s template to the Guardfile.

# File lib/guard/plugin_util.rb, line 126
def add_to_guardfile
  klass = plugin_class # call here to avoid failing later

  require_relative "guardfile/evaluator"
  # TODO: move this to Generator?
  options = Guard.state.session.evaluator_options
  evaluator = Guardfile::Evaluator.new(options)
  begin
    evaluator.evaluate
  rescue Guard::Guardfile::Evaluator::NoPluginsError
  end

  if evaluator.guardfile_include?(name)
    UI.info "Guardfile already includes #{ name } guard"
  else
    content = File.read("Guardfile")
    File.open("Guardfile", "wb") do |f|
      f.puts(content)
      f.puts("")
      f.puts(klass.template(plugin_location))
    end

    UI.info INFO_ADDED_GUARD_TO_GUARDFILE % name
  end
end
initialize_plugin(options) click to toggle source

Initializes a new ‘Guard::Plugin` with the given `options` hash. This methods handles plugins that inherit from the deprecated `Guard::Guard` class as well as plugins that inherit from `Guard::Plugin`.

@see Guard::Plugin @see github.com/guard/guard/wiki/Upgrading-to-Guard-2.0 How to upgrade for Guard 2.0

@return [Guard::Plugin] the initialized plugin @return [Guard::Guard] the initialized plugin. This return type is

deprecated and the plugin's maintainer should update it to be
compatible with Guard 2.0. For more information on how to upgrade for
Guard 2.0, please head over to:
https://github.com/guard/guard/wiki/Upgrading-to-Guard-2.0
# File lib/guard/plugin_util.rb, line 55
def initialize_plugin(options)
  klass = plugin_class
  fail "Could not load class: #{_constant_name.inspect}" unless klass
  if klass.ancestors.include?(Guard)
    klass.new(options.delete(:watchers), options)
  else
    begin
      klass.new(**options)
    rescue ArgumentError => e
      fail "Failed to call #{klass}.new(options): #{e}"
    end
  end
end
plugin_class(options = {}) click to toggle source

Tries to load the Guard plugin main class. This transforms the supplied plugin name into a class name:

  • ‘guardname` will become `Guard::Guardname`

  • ‘dashed-guard-name` will become `Guard::DashedGuardName`

  • ‘underscore_guard_name` will become `Guard::UnderscoreGuardName`

When no class is found with the strict case sensitive rules, another try is made to locate the class without matching case:

  • ‘rspec` will find a class `Guard::RSpec`

@option options [Boolean] fail_gracefully whether error messages should not be printed

@return [Class, nil] the loaded class

# File lib/guard/plugin_util.rb, line 96
def plugin_class(options = {})
  options = { fail_gracefully: false }.merge(options)

  const = _plugin_constant
  fail TypeError, "no constant: #{_constant_name}" unless const
  @plugin_class ||= Guard.const_get(const)

rescue TypeError
  begin
    require "guard/#{ name.downcase }"
    const = _plugin_constant
    @plugin_class ||= Guard.const_get(const)

  rescue TypeError => error
    UI.error "Could not find class Guard::#{ _constant_name }"
    UI.error error.backtrace.join("\n")
    # TODO: return value or move exception higher
  rescue LoadError => error
    unless options[:fail_gracefully]
      msg = format(ERROR_NO_GUARD_OR_CLASS, name.downcase, _constant_name)
      UI.error(msg)
      UI.error("Error is: #{error}")
      UI.error(error.backtrace.join("\n"))
      # TODO: return value or move exception higher
    end
  end
end
plugin_location() click to toggle source

Locates a path to a Guard plugin gem.

@return [String] the full path to the plugin gem

# File lib/guard/plugin_util.rb, line 73
def plugin_location
  @plugin_location ||= _full_gem_path("guard-#{name}")
rescue Gem::LoadError
  UI.error "Could not find 'guard-#{ name }' gem path."
end

Private Instance Methods

_constant_name() click to toggle source

Guesses the most probable name for the current plugin based on its name.

@example Returns the most probable name for a plugin

> Guard::PluginUtil.new('rspec').send(:_constant_name)
=> "Rspec"
# File lib/guard/plugin_util.rb, line 172
def _constant_name
  @_constant_name ||= name.gsub(%r{/(.?)}) { "::#{ $1.upcase }" }.
                      gsub(/(?:^|[_-])(.)/) { $1.upcase }
end
_full_gem_path(name) click to toggle source
# File lib/guard/plugin_util.rb, line 177
def _full_gem_path(name)
  Gem::Specification.find_by_name(name).full_gem_path
end
_plugin_constant() click to toggle source

Returns the constant for the current plugin.

@example Returns the constant for a plugin

> Guard::PluginUtil.new('rspec').send(:_plugin_constant)
=> Guard::RSpec
# File lib/guard/plugin_util.rb, line 160
def _plugin_constant
  @_plugin_constant ||= Guard.constants.detect do |c|
    c.to_s.casecmp(_constant_name.downcase).zero?
  end
end