Class: RuboCop::Cop::Style::EmptyLiteral
Relationships & Source Files | |
Super Chains via Extension / Inclusion / Inheritance | |
Class Chain:
self,
::RuboCop::Cop::AutoCorrector ,
::RuboCop::Cop::Base ,
::RuboCop::ExcludeLimit ,
NodePattern::Macros,
RuboCop::AST::Sexp
|
|
Instance Chain:
|
|
Inherits: |
RuboCop::Cop::Base
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Defined in: | lib/rubocop/cop/style/empty_literal.rb |
Overview
Checks for the use of a method, the result of which would be a literal, like an empty array, hash, or string.
Constant Summary
-
ARR_MSG =
# File 'lib/rubocop/cop/style/empty_literal.rb', line 27'Use array literal `[]` instead of `%<current>s`.'
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HASH_MSG =
# File 'lib/rubocop/cop/style/empty_literal.rb', line 28'Use hash literal `{}` instead of `%<current>s`.'
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RESTRICT_ON_SEND =
# File 'lib/rubocop/cop/style/empty_literal.rb', line 31%i[new [] Array Hash].freeze
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STR_MSG =
# File 'lib/rubocop/cop/style/empty_literal.rb', line 29'Use string literal `%<prefer>s` instead of `String.new`.'
::RuboCop::Cop::Base
- Inherited
EMPTY_OFFENSES, RESTRICT_ON_SEND
::RuboCop::Cop::FrozenStringLiteral
- Included
FROZEN_STRING_LITERAL, FROZEN_STRING_LITERAL_ENABLED, FROZEN_STRING_LITERAL_TYPES_RUBY27
::RuboCop::Cop::RangeHelp
- Included
Class Attribute Summary
::RuboCop::Cop::AutoCorrector
- Extended
::RuboCop::Cop::Base
- Inherited
.gem_requirements, .lint?, | |
.support_autocorrect? | Returns if class supports autocorrect. |
.support_multiple_source? | Override if your cop should be called repeatedly for multiple investigations Between calls to |
Class Method Summary
::RuboCop::Cop::Base
- Inherited
.autocorrect_incompatible_with | List of cops that should not try to autocorrect at the same time as this cop. |
.badge | Naming. |
.callbacks_needed, .cop_name, .department, | |
.documentation_url | Returns a url to view this cops documentation online. |
.exclude_from_registry | Call for abstract Cop classes. |
.inherited, | |
.joining_forces | Override and return the Force class(es) you need to join. |
.match? | Returns true if the cop name or the cop namespace matches any of the given names. |
.new, | |
.requires_gem | Register a version requirement for the given gem name. |
.restrict_on_send |
::RuboCop::ExcludeLimit
- Extended
exclude_limit | Sets up a configuration option to have an exclude limit tracked. |
transform |
Instance Attribute Summary
- #frozen_strings? ⇒ Boolean readonly private
::RuboCop::Cop::StringLiteralsHelp
- Included
::RuboCop::Cop::Base
- Inherited
::RuboCop::Cop::AutocorrectLogic
- Included
Instance Method Summary
- #array_node(node)
- #array_with_block(node)
- #array_with_index(node)
- #hash_node(node)
- #hash_with_block(node)
- #hash_with_index(node)
- #on_send(node)
- #str_node(node)
- #correction(node) private
- #first_argument_unparenthesized?(node) ⇒ Boolean private
- #offense_array_node?(node) ⇒ Boolean private
- #offense_hash_node?(node) ⇒ Boolean private
- #offense_message(node) private
- #replacement_range(node) private
::RuboCop::Cop::StringLiteralsHelp
- Included
::RuboCop::Cop::RangeHelp
- Included
#add_range, #column_offset_between, | |
#contents_range | A range containing only the contents of a literal with delimiters (e.g. |
#directions, | |
#effective_column | Returns the column attribute of the range, except if the range is on the first line and there’s a byte order mark at the beginning of that line, in which case 1 is subtracted from the column value. |
#final_pos, #move_pos, #move_pos_str, #range_between, #range_by_whole_lines, #range_with_comments, #range_with_comments_and_lines, #range_with_surrounding_comma, #range_with_surrounding_space, #source_range |
::RuboCop::Cop::FrozenStringLiteral
- Included
::RuboCop::Cop::Base
- Inherited
#add_global_offense | Adds an offense that has no particular location. |
#add_offense | Adds an offense on the specified range (or node with an expression) Unless that offense is disabled for this range, a corrector will be yielded to provide the cop the opportunity to autocorrect the offense. |
#begin_investigation | Called before any investigation. |
#callbacks_needed, | |
#cop_config | Configuration Helpers. |
#cop_name, #excluded_file?, | |
#external_dependency_checksum | This method should be overridden when a cop’s behavior depends on state that lives outside of these locations: |
#inspect, | |
#message | Gets called if no message is specified when calling |
#name | Alias for Base#cop_name. |
#offenses, | |
#on_investigation_end | Called after all on_… |
#on_new_investigation | Called before all on_… |
#on_other_file | Called instead of all on_… |
#parse | There should be very limited reasons for a Cop to do it’s own parsing. |
#parser_engine, | |
#ready | Called between investigations. |
#relevant_file?, #target_rails_version, #target_ruby_version, #annotate, #apply_correction, #attempt_correction, | |
#callback_argument | Reserved for Cop::Cop. |
#complete_investigation | Called to complete an investigation. |
#correct, #current_corrector, | |
#current_offense_locations | Reserved for Commissioner: |
#current_offenses, #currently_disabled_lines, #custom_severity, #default_severity, #disable_uncorrectable, #enabled_line?, #file_name_matches_any?, #find_message, #find_severity, #range_for_original, #range_from_node_or_range, | |
#reset_investigation | Actually private methods. |
#use_corrector |
::RuboCop::Cop::AutocorrectLogic
- Included
#disable_offense, #disable_offense_at_end_of_line, #disable_offense_before_and_after, #disable_offense_with_eol_or_surround_comment, #heredoc_range, #max_line_length, #multiline_ranges, #multiline_string?, | |
#range_by_lines | Expand the given range to include all of any lines it covers. |
#range_of_first_line, #range_overlaps_offense?, #string_continuation?, #surrounding_heredoc?, #surrounding_percent_array? |
::RuboCop::Cop::IgnoredNode
- Included
Constructor Details
This class inherits a constructor from RuboCop::Cop::Base
Instance Attribute Details
#frozen_strings? ⇒ Boolean
(readonly, private)
[ GitHub ]
# File 'lib/rubocop/cop/style/empty_literal.rb', line 136
def frozen_strings? return true if frozen_string_literals_enabled? frozen_string_cop_enabled = config.for_cop('Style/FrozenStringLiteralComment')['Enabled'] frozen_string_cop_enabled && !frozen_string_literals_disabled? && string_literals_frozen_by_default?.nil? end
Instance Method Details
#array_node(node)
[ GitHub ]# File 'lib/rubocop/cop/style/empty_literal.rb', line 34
def_node_matcher :array_node, '(send (const {nil? cbase} :Array) :new (array)?)'
#array_with_block(node)
[ GitHub ]# File 'lib/rubocop/cop/style/empty_literal.rb', line 43
def_node_matcher :array_with_block, '(block (send (const {nil? cbase} :Array) :new) args _)'
#array_with_index(node)
[ GitHub ]# File 'lib/rubocop/cop/style/empty_literal.rb', line 54
def_node_matcher :array_with_index, <<~PATTERN { (send (const {nil? cbase} :Array) :[]) (send nil? :Array (array)) } PATTERN
#correction(node) (private)
[ GitHub ]# File 'lib/rubocop/cop/style/empty_literal.rb', line 118
def correction(node) if offense_array_node?(node) '[]' elsif str_node(node) preferred_string_literal elsif offense_hash_node?(node) if first_argument_unparenthesized?(node) # `some_method {}` is not same as `some_method Hash.new` # because the braces are interpreted as a block. We will have # to rewrite the arguments to wrap them in parenthesis. args = node.parent.arguments "(#{args[1..].map(&:source).unshift('{}').join(', ')})" else '{}' end end end
#first_argument_unparenthesized?(node) ⇒ Boolean
(private)
# File 'lib/rubocop/cop/style/empty_literal.rb', line 89
def first_argument_unparenthesized?(node) parent = node.parent return false unless parent && %i[send super zsuper].include?(parent.type) node.equal?(parent.first_argument) && !parentheses?(node.parent) end
#hash_node(node)
[ GitHub ]# File 'lib/rubocop/cop/style/empty_literal.rb', line 37
def_node_matcher :hash_node, '(send (const {nil? cbase} :Hash) :new)'
#hash_with_block(node)
[ GitHub ]# File 'lib/rubocop/cop/style/empty_literal.rb', line 46
def_node_matcher :hash_with_block, <<~PATTERN { (block (send (const {nil? cbase} :Hash) :new) args _) (numblock (send (const {nil? cbase} :Hash) :new) ...) } PATTERN
#hash_with_index(node)
[ GitHub ]# File 'lib/rubocop/cop/style/empty_literal.rb', line 62
def_node_matcher :hash_with_index, <<~PATTERN { (send (const {nil? cbase} :Hash) :[]) (send nil? :Hash (array)) } PATTERN
#offense_array_node?(node) ⇒ Boolean
(private)
# File 'lib/rubocop/cop/style/empty_literal.rb', line 109
def offense_array_node?(node) (array_node(node) && !array_with_block(node.parent)) || array_with_index(node) end
#offense_hash_node?(node) ⇒ Boolean
(private)
# File 'lib/rubocop/cop/style/empty_literal.rb', line 113
def offense_hash_node?(node) # If Hash.new takes a block, it can't be changed to {}. (hash_node(node) && !hash_with_block(node.parent)) || hash_with_index(node) end
#offense_message(node) (private)
[ GitHub ]# File 'lib/rubocop/cop/style/empty_literal.rb', line 79
def (node) if offense_array_node?(node) format(ARR_MSG, current: node.source) elsif offense_hash_node?(node) format(HASH_MSG, current: node.source) elsif str_node(node) && !frozen_strings? format(STR_MSG, prefer: preferred_string_literal) end end
#on_send(node)
[ GitHub ]# File 'lib/rubocop/cop/style/empty_literal.rb', line 69
def on_send(node) return unless ( = (node)) add_offense(node, message: ) do |corrector| corrector.replace(replacement_range(node), correction(node)) end end
#replacement_range(node) (private)
[ GitHub ]# File 'lib/rubocop/cop/style/empty_literal.rb', line 96
def replacement_range(node) if hash_node(node) && first_argument_unparenthesized?(node) # `some_method {}` is not same as `some_method Hash.new` # because the braces are interpreted as a block. We will have # to rewrite the arguments to wrap them in parenthesis. args = node.parent.arguments range_between(args[0].source_range.begin_pos - 1, args[-1].source_range.end_pos) else node.source_range end end
#str_node(node)
[ GitHub ]# File 'lib/rubocop/cop/style/empty_literal.rb', line 40
def_node_matcher :str_node, '(send (const {nil? cbase} :String) :new)'