Class: RuboCop::Cop::Lint::ToJSON

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

Overview

This cop checks to make sure `#to_json` includes an optional argument. When overriding `#to_json`, callers may invoke JSON generation via `JSON.generate(your_obj)`. Since `JSON#generate` allows for an optional argument, your method should too.

Examples:

class Point
  attr_reader :x, :y

  # bad, incorrect arity
  def to_json
    JSON.generate([x, y])
  end

  # good, preserving args
  def to_json(*args)
    JSON.generate([x, y], *args)
  end

  # good, discarding args
  def to_json(*_args)
    JSON.generate([x, y])
  end
end

Constant Summary collapse

MSG =
'`#to_json` requires an optional argument to be parsable via JSON.generate(obj).'

Constants inherited from Base

Base::RESTRICT_ON_SEND

Instance Attribute Summary

Attributes inherited from Base

#config, #processed_source

Instance Method Summary collapse

Methods included from AutoCorrector

support_autocorrect?

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_def(node) ⇒ Object


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# File 'lib/rubocop/cop/lint/to_json.rb', line 36

def on_def(node)
  return unless node.method?(:to_json) && node.arguments.empty?

  add_offense(node) do |corrector|
    # The following used `*_args` because `to_json(*args)` has
    # an offense of `Lint/UnusedMethodArgument` cop if `*args`
    # is not used.
    corrector.insert_after(node.loc.name, '(*_args)')
  end
end