Class: RuboCop::Cop::Lint::NestedMethodDefinition

Inherits:
Base
  • Object
show all
Includes:
AllowedMethods, AllowedPattern
Defined in:
lib/rubocop/cop/lint/nested_method_definition.rb

Overview

Checks for nested method definitions.

Examples:


# bad

# `bar` definition actually produces methods in the same scope
# as the outer `foo` method. Furthermore, the `bar` method
# will be redefined every time `foo` is invoked.
def foo
  def bar
  end
end

# good

def foo
  bar = -> { puts 'hello' }
  bar.call
end

# good

# `class_eval`, `instance_eval`, `module_eval`, `class_exec`, `instance_exec`, and
# `module_exec` blocks are allowed by default.

def foo
  self.class.class_eval do
    def bar
    end
  end
end

def foo
  self.class.module_exec do
    def bar
    end
  end
end

# good

def foo
  class << self
    def bar
    end
  end
end

AllowedMethods: [] (default)

# bad
def do_something
  has_many :articles do
    def find_or_create_by_name(name)
    end
  end
end

AllowedMethods: ['has_many']

# bad
def do_something
  has_many :articles do
    def find_or_create_by_name(name)
    end
  end
end

AllowedPatterns: [] (default)

# bad
def foo(obj)
  obj.do_baz do
    def bar
    end
  end
end

AllowedPatterns: ['baz']

# good
def foo(obj)
  obj.do_baz do
    def bar
    end
  end
end

Constant Summary collapse

MSG =
'Method definitions must not be nested. Use `lambda` instead.'

Constants inherited from Base

Base::RESTRICT_ON_SEND

Instance Attribute Summary

Attributes inherited from Base

#config, #processed_source

Instance Method Summary collapse

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

#on_def(node) ⇒ Object Also known as: on_defs



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# File 'lib/rubocop/cop/lint/nested_method_definition.rb', line 103

def on_def(node)
  subject, = *node
  return if node.defs_type? && subject.lvar_type?

  def_ancestor = node.each_ancestor(:def, :defs).first
  return unless def_ancestor

  within_scoping_def =
    node.each_ancestor(:block, :numblock, :sclass).any? do |ancestor|
      scoping_method_call?(ancestor)
    end

  add_offense(node) if def_ancestor && !within_scoping_def
end