Class: RuboCop::Cop::Style::SafeNavigation
- Includes:
- NilMethods, RangeHelp
- Defined in:
- lib/rubocop/cop/style/safe_navigation.rb
Overview
This cop transforms usages of a method call safeguarded by a non ‘nil` check for the variable whose method is being called to safe navigation (`&.`). If there is a method chain, all of the methods in the chain need to be checked for safety, and all of the methods will need to be changed to use safe navigation. We have limited the cop to not register an offense for method chains that exceed 2 methods.
Configuration option: ConvertCodeThatCanStartToReturnNil The default for this is ‘false`. When configured to `true`, this will check for code in the format `!foo.nil? && foo.bar`. As it is written, the return of this code is limited to `false` and whatever the return of the method is. If this is converted to safe navigation, `foo&.bar` can start returning `nil` as well as what the method returns.
Constant Summary collapse
- MSG =
'Use safe navigation (`&.`) instead of checking if an object ' \ 'exists before calling the method.'
- LOGIC_JUMP_KEYWORDS =
%i[break fail next raise return throw yield].freeze
Constants included from Util
Instance Attribute Summary
Attributes inherited from Cop
#config, #corrections, #offenses, #processed_source
Instance Method Summary collapse
- #autocorrect(node) ⇒ Object
- #check_node(node) ⇒ Object
- #on_and(node) ⇒ Object
- #on_if(node) ⇒ Object
- #use_var_only_in_unless_modifier?(node, variable) ⇒ Boolean
Methods inherited from Cop
#add_offense, all, autocorrect_incompatible_with, badge, #config_to_allow_offenses, #config_to_allow_offenses=, #cop_config, cop_name, #cop_name, #correct, department, #duplicate_location?, #excluded_file?, #find_location, #highlights, inherited, #initialize, #join_force?, lint?, match?, #message, #messages, non_rails, #parse, qualified_cop_name, #relevant_file?, #target_rails_version, #target_ruby_version
Methods included from AST::Sexp
Methods included from NodePattern::Macros
#def_node_matcher, #def_node_search, #node_search, #node_search_all, #node_search_body, #node_search_first
Methods included from AutocorrectLogic
#autocorrect?, #autocorrect_enabled?, #autocorrect_requested?, #support_autocorrect?
Methods included from IgnoredNode
#ignore_node, #ignored_node?, #part_of_ignored_node?
Methods included from Util
begins_its_line?, comment_line?, double_quotes_required?, escape_string, first_part_of_call_chain, interpret_string_escapes, line_range, needs_escaping?, on_node, parentheses?, same_line?, to_string_literal, to_supported_styles, tokens, trim_string_interporation_escape_character
Methods included from PathUtil
absolute?, chdir, hidden_dir?, hidden_file_in_not_hidden_dir?, match_path?, pwd, relative_path, reset_pwd, smart_path
Constructor Details
This class inherits a constructor from RuboCop::Cop::Cop
Instance Method Details
#autocorrect(node) ⇒ Object
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# File 'lib/rubocop/cop/style/safe_navigation.rb', line 114 def autocorrect(node) _check, body, = node.node_parts _checked_variable, matching_receiver, = extract_parts(node) method_call, = matching_receiver.parent lambda do |corrector| corrector.remove(begin_range(node, body)) corrector.remove(end_range(node, body)) corrector.insert_before(method_call.loc.dot, '&') add_safe_nav_to_all_methods_in_chain(corrector, method_call, body) end end |
#check_node(node) ⇒ Object
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# File 'lib/rubocop/cop/style/safe_navigation.rb', line 98 def check_node(node) checked_variable, receiver, method_chain, method = extract_parts(node) return unless receiver == checked_variable return if use_var_only_in_unless_modifier?(node, checked_variable) # method is already a method call so this is actually checking for a # chain greater than 2 return if chain_size(method_chain, method) > 1 return if unsafe_method_used?(method_chain, method) add_offense(node) end |
#on_and(node) ⇒ Object
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# File 'lib/rubocop/cop/style/safe_navigation.rb', line 94 def on_and(node) check_node(node) end |
#on_if(node) ⇒ Object
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# File 'lib/rubocop/cop/style/safe_navigation.rb', line 88 def on_if(node) return if allowed_if_condition?(node) check_node(node) end |
#use_var_only_in_unless_modifier?(node, variable) ⇒ Boolean
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# File 'lib/rubocop/cop/style/safe_navigation.rb', line 110 def use_var_only_in_unless_modifier?(node, variable) node.if_type? && node.unless? && !method_called?(variable) end |