Class: RuboCop::Cop::Style::GuardClause

Inherits:
Base
  • Object
show all
Includes:
MinBodyLength, RuboCop::Cop::StatementModifier
Defined in:
lib/rubocop/cop/style/guard_clause.rb

Overview

Use a guard clause instead of wrapping the code inside a conditional expression

Examples:

# bad
def test
  if something
    work
  end
end

# good
def test
  return unless something

  work
end

# also good
def test
  work if something
end

# bad
if something
  raise 'exception'
else
  ok
end

# good
raise 'exception' if something
ok

# bad
if something
  foo || raise('exception')
else
  ok
end

# good
foo || raise('exception') if something
ok

Constant Summary collapse

MSG = 
'Use a guard clause (`%<example>s`) instead of wrapping the ' \
'code inside a conditional expression.'

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

#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 Also known as: on_defs 


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# File 'lib/rubocop/cop/style/guard_clause.rb', line 57

def on_def(node)
  body = node.body

  return unless body

  if body.if_type?
    check_ending_if(body)
  elsif body.begin_type?
    final_expression = body.children.last
    check_ending_if(final_expression) if final_expression&.if_type?
  end
end

#on_if(node) ⇒ Object 


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# File 'lib/rubocop/cop/style/guard_clause.rb', line 71

def on_if(node)
  return if accepted_form?(node)

  guard_clause_in_if = node.if_branch&.guard_clause?
  guard_clause_in_else = node.else_branch&.guard_clause?
  guard_clause = guard_clause_in_if || guard_clause_in_else
  return unless guard_clause

  kw = if guard_clause_in_if
         node.loc.keyword.source
       else
         opposite_keyword(node)
       end

  register_offense(node, guard_clause_source(guard_clause), kw)
end