Class: RuboCop::Cop::Style::EnvHome

Inherits:
Base
  • Object
show all
Extended by:
AutoCorrector
Defined in:
lib/rubocop/cop/style/env_home.rb

Overview

Checks for consistent usage of ENV['HOME']. If nil is used as the second argument of ENV.fetch, it is treated as a bad case like ENV[].

Examples:


# bad
ENV['HOME']
ENV.fetch('HOME', nil)

# good
Dir.home

# good
ENV.fetch('HOME', default)

Cop Safety Information:

  • The cop is unsafe because the result when nil is assigned to ENV['HOME'] changes:

    ENV['HOME'] = nil
    ENV['HOME'] # => nil
    Dir.home    # => '/home/foo'

Constant Summary collapse

MSG =
'Use `Dir.home` instead.'
RESTRICT_ON_SEND =
%i[[] fetch].freeze

Instance Attribute Summary

Attributes inherited from Base

#config, #processed_source

Instance Method Summary collapse

Methods included from AutoCorrector

support_autocorrect?

Methods inherited from Base

#active_support_extensions_enabled?, #add_global_offense, #add_offense, autocorrect_incompatible_with, badge, #begin_investigation, callbacks_needed, #callbacks_needed, #config_to_allow_offenses, #config_to_allow_offenses=, #cop_config, cop_name, #cop_name, department, documentation_url, exclude_from_registry, #excluded_file?, #external_dependency_checksum, inherited, #initialize, #inspect, joining_forces, lint?, match?, #message, #offenses, #on_investigation_end, #on_new_investigation, #on_other_file, #parse, #ready, #relevant_file?, support_autocorrect?, support_multiple_source?, #target_rails_version, #target_ruby_version

Methods included from ExcludeLimit

#exclude_limit

Methods included from AutocorrectLogic

#autocorrect?, #autocorrect_enabled?, #autocorrect_requested?, #autocorrect_with_disable_uncorrectable?, #correctable?, #disable_uncorrectable?, #safe_autocorrect?

Methods included from IgnoredNode

#ignore_node, #ignored_node?, #part_of_ignored_node?

Methods included from Util

silence_warnings

Constructor Details

This class inherits a constructor from RuboCop::Cop::Base

Instance Method Details

#env_home?(node) ⇒ Object



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# File 'lib/rubocop/cop/style/env_home.rb', line 38

def_node_matcher :env_home?, <<~PATTERN
  (send
    (const {cbase nil?} :ENV) {:[] :fetch}
    (str "HOME")
    ...)
PATTERN

#on_send(node) ⇒ Object



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# File 'lib/rubocop/cop/style/env_home.rb', line 45

def on_send(node)
  return unless env_home?(node)
  return if node.arguments.count == 2 && !node.arguments[1].nil_type?

  add_offense(node) do |corrector|
    corrector.replace(node, 'Dir.home')
  end
end