Class: RuboCop::Cop::Lint::TripleQuotes

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
Defined in: lib/rubocop/cop/lint/triple_quotes.rb


Checks for "triple quotes" (strings delimited by any odd number of quotes greater than 1).

Ruby allows multiple strings to be implicitly concatenated by just being adjacent in a statement (ie. "foo""bar" == "foobar"). This sometimes gives the impression that there is something special about triple quotes, but in fact it is just extra unnecessary quotes and produces the same string. Each pair of quotes produces an additional concatenated empty string, so the result is still only the "actual" string within the delimiters.

Although this cop is called triple quotes, the same behavior is present for strings delimited by 5, 7, etc. quotation marks.


# bad
  A string

# bad
  A string

# good
  A string

# good
  A string

# good (but not the same spacing as the bad case)
'A string'

Constant Summary

::RuboCop::Cop::Base - Inherited


Class Attribute Summary

::RuboCop::Cop::AutoCorrector - Extended

::RuboCop::Cop::Base - Inherited

.gem_requirements, .lint?,

Returns if class supports autocorrect.


Override if your cop should be called repeatedly for multiple investigations Between calls to on_new_investigation and on_investigation_end, the result of processed_source will remain constant.

Class Method Summary

::RuboCop::Cop::Base - Inherited


List of cops that should not try to autocorrect at the same time as this cop.



.callbacks_needed, .cop_name, .department,

Returns an url to view this cops documentation online.


Call for abstract Cop classes.


Override and return the Force class(es) you need to join.


Returns true if the cop name or the cop namespace matches any of the given names.


Register a version requirement for the given gem name.


::RuboCop::ExcludeLimit - Extended


Sets up a configuration option to have an exclude limit tracked.


Instance Attribute Summary

Instance Method Summary

::RuboCop::Cop::Base - Inherited


Adds an offense that has no particular location.


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.


Called before any investigation.


Configuration Helpers.

#cop_name, #excluded_file?,

This method should be overridden when a cop’s behavior depends on state that lives outside of these locations:


Gets called if no message is specified when calling add_offense or add_global_offense Cops are discouraged to override this; instead pass your message directly.


Alias for Base#cop_name.


Called after all on_…​


Called before all on_…​


Called instead of all on_…​


There should be very limited reasons for a Cop to do it’s own parsing.


Called between investigations.

#relevant_file?, #target_rails_version, #target_ruby_version, #annotate, #apply_correction, #attempt_correction,

Reserved for Cop::Cop.


Called to complete an investigation.

#correct, #current_corrector,

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,

Actually private methods.


::RuboCop::Cop::AutocorrectLogic - Included

::RuboCop::Cop::IgnoredNode - Included

Constructor Details

This class inherits a constructor from RuboCop::Cop::Base

Instance Method Details

#empty_str_nodes(node) (private)

[ GitHub ]

# File 'lib/rubocop/cop/lint/triple_quotes.rb', line 65

def empty_str_nodes(node)
  node.each_child_node(:str).select { |str| str.value == '' }


[ GitHub ]

# File 'lib/rubocop/cop/lint/triple_quotes.rb', line 47

def on_dstr(node)
  return if (empty_str_nodes = empty_str_nodes(node)).none?

  opening_quotes = node.source.scan(/(?<=\A)['"]*/)[0]
  return if opening_quotes.size < 3

  # If the node is composed of only empty `str` nodes, keep one
  empty_str_nodes.shift if empty_str_nodes.size == node.child_nodes.size

  add_offense(node) do |corrector|
    empty_str_nodes.each do |str|