Class: RuboCop::Cop::Lint::SymbolConversion

Inherits:
Base
  • Object
show all
Extended by:
AutoCorrector
Includes:
ConfigurableEnforcedStyle, SymbolHelp
Defined in:
lib/rubocop/cop/lint/symbol_conversion.rb

Overview

This cop checks for uses of literal strings converted to a symbol where a literal symbol could be used instead.

There are two possible styles for this cop. `strict` (default) will register an offense for any incorrect usage. `consistent` additionally requires hashes to use the same style for every symbol key (ie. if any symbol key needs to be quoted it requires all keys to be quoted).

Examples:

# bad
'string'.to_sym
:symbol.to_sym
'underscored_string'.to_sym
:'underscored_symbol'
'hyphenated-string'.to_sym

# good
:string
:symbol
:underscored_string
:underscored_symbol
:'hyphenated-string'

EnforcedStyle: strict (default)


# bad
{
  'a': 1,
  "b": 2,
  'c-d': 3
}

# good (don't quote keys that don't require quoting)
{
  a: 1,
  b: 2,
  'c-d': 3
}

EnforcedStyle: consistent


# bad
{
  a: 1,
  'b-c': 2
}

# good (quote all keys if any need quoting)
{
  'a': 1,
  'b-c': 2
}

# good (no quoting required)
{
  a: 1,
  b: 2
}

Constant Summary collapse

MSG =
'Unnecessary symbol conversion; use `%<correction>s` instead.'
MSG_CONSISTENCY =
'Symbol hash key should be quoted for consistency; ' \
'use `%<correction>s` instead.'
RESTRICT_ON_SEND =
%i[to_sym intern].freeze

Instance Attribute Summary

Attributes inherited from Base

#config, #processed_source

Instance Method Summary collapse

Methods included from AutoCorrector

support_autocorrect?

Methods included from SymbolHelp

#hash_key?

Methods included from ConfigurableEnforcedStyle

#alternative_style, #alternative_styles, #ambiguous_style_detected, #correct_style_detected, #detected_style, #detected_style=, #no_acceptable_style!, #no_acceptable_style?, #opposite_style_detected, #style, #style_configured?, #style_detected, #style_parameter_name, #supported_styles, #unexpected_style_detected

Methods inherited from Base

#add_global_offense, #add_offense, autocorrect_incompatible_with, badge, #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, 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?, #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

#on_hash(node) ⇒ Object


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# File 'lib/rubocop/cop/lint/symbol_conversion.rb', line 100

def on_hash(node)
  # For `EnforcedStyle: strict`, hash keys are evaluated in `on_sym`
  return unless style == :consistent

  keys = node.keys.select(&:sym_type?)

  if keys.any? { |key| requires_quotes?(key) }
    correct_inconsistent_hash_keys(keys)
  else
    # If there are no symbol keys requiring quoting,
    # treat the hash like `EnforcedStyle: strict`.
    keys.each { |key| correct_hash_key(key) }
  end
end

#on_send(node) ⇒ Object


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# File 'lib/rubocop/cop/lint/symbol_conversion.rb', line 76

def on_send(node)
  return unless node.receiver
  return unless node.receiver.str_type? || node.receiver.sym_type?

  register_offense(node, correction: node.receiver.value.to_sym.inspect)
end

#on_sym(node) ⇒ Object


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# File 'lib/rubocop/cop/lint/symbol_conversion.rb', line 83

def on_sym(node)
  return if ignored_node?(node) || properly_quoted?(node.source, node.value.inspect)

  # `alias` arguments are symbols but since a symbol that requires
  # being quoted is not a valid method identifier, it can be ignored
  return if in_alias?(node)

  # The `%I[]` and `%i[]` macros are parsed as normal arrays of symbols
  # so they need to be ignored.
  return if in_percent_literal_array?(node)

  # Symbol hash keys have a different format and need to be handled separately
  return correct_hash_key(node) if hash_key?(node)

  register_offense(node, correction: node.value.inspect)
end