Class: RuboCop::Cop::Lint::NumberConversion

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: self, `::RuboCop::Cop::AllowedPattern`, `::RuboCop::Cop::AllowedMethods`, `::RuboCop::Cop::Base`, `::RuboCop::Cop::AutocorrectLogic`, `::RuboCop::Cop::IgnoredNode`, `::RuboCop::Util`, RuboCop::AST::Sexp
Inherits:	RuboCop::Cop::Base Object RuboCop::Cop::Base RuboCop::Cop::Lint::NumberConversion
Defined in:	lib/rubocop/cop/lint/number_conversion.rb

Overview

Warns the usage of unsafe number conversions. Unsafe number conversion can cause unexpected error if auto type conversion fails. Cop prefer parsing with number class instead.

Conversion with Integer, Float, etc. will raise an ArgumentError if given input that is not numeric (eg. an empty string), whereas to_i, etc. will try to convert regardless of input (''.to_i ⇒ 0). As such, this cop is disabled by default because it’s not necessarily always correct to raise if a value is not numeric.

Note

Some values cannot be converted properly using one of the Kernel method (for instance, Time and DateTime values are allowed by this cop by default). Similarly, Rails' duration methods do not work well with Integer() and can be allowed with AllowedMethods. By default, there are no methods to allowed.

Examples:

# bad

'10'.to_i
'10.2'.to_f
'10'.to_c
'1/3'.to_r
['1', '2', '3'].map(&:to_i)
foo.try(:to_f)
bar.send(:to_c)

# good

Integer('10', 10)
Float('10.2')
Complex('10')
Rational('1/3')
['1', '2', '3'].map { |i| Integer(i, 10) }
foo.try { |i| Float(i) }
bar.send { |i| Complex(i) }

AllowedMethods: [] (default)

# bad
10.minutes.to_i

AllowedMethods: [minutes]

# good
10.minutes.to_i

AllowedPatterns: [] (default)

# bad
10.minutes.to_i

AllowedPatterns: ['min*']

# good
10.minutes.to_i

IgnoredClasses: [Time, DateTime] (default)

# good
Time.now.to_datetime.to_i

Cop Safety Information:

Autocorrection is unsafe because it is not guaranteed that the replacement Kernel methods are able to properly handle the input if it is not a standard class.

Constant Summary

CONVERSION_METHODS =
# File 'lib/rubocop/cop/lint/number_conversion.rb', line 89
```
%i[Integer Float Complex Rational to_i to_f to_c to_r].freeze
```

CONVERSION_METHOD_CLASS_MAPPING =
# File 'lib/rubocop/cop/lint/number_conversion.rb', line 79

{
  to_i: "#{Integer.name}(%<number_object>s, 10)",
  to_f: "#{Float.name}(%<number_object>s)",
  to_c: "#{Complex.name}(%<number_object>s)",
  to_r: "#{Rational.name}(%<number_object>s)"
}.freeze

METHODS =
# File 'lib/rubocop/cop/lint/number_conversion.rb', line 90
```
CONVERSION_METHOD_CLASS_MAPPING.keys.map(&:inspect).join(' ')
```

MSG =
# File 'lib/rubocop/cop/lint/number_conversion.rb', line 85

'Replace unsafe number conversion with number ' \
'class parsing, instead of using ' \
'`%<current>s`, use stricter ' \
'`%<corrected_method>s`.'

`::RuboCop::Cop::Base` - Inherited

EMPTY_OFFENSES, RESTRICT_ON_SEND

Class Attribute Summary

`::RuboCop::Cop::AutoCorrector` - Extended

support_autocorrect?

`::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 `on_new_investigation` and `on_investigation_end`, the result of `processed_source` will remain constant.
.builtin?

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	Cops (other than builtin) are encouraged to implement this.
.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

`::RuboCop::Cop::Base` - Inherited

#active_support_extensions_enabled?, #always_autocorrect?, #config, #config_to_allow_offenses, #config_to_allow_offenses=, #contextual_autocorrect?, #processed_source, #target_satisfies_all_gem_version_requirements?

`::RuboCop::Cop::AutocorrectLogic` - Included

#autocorrect?, #autocorrect_enabled?, #autocorrect_requested?, #autocorrect_with_disable_uncorrectable?, #correctable?, #disable_uncorrectable?, #safe_autocorrect?

Instance Method Summary

#on_csend(node)

Alias for #on_send.
#on_send(node) (also: #on_csend)
#to_method(node)
#to_method_symbol(node)
#allow_receiver?(receiver) ⇒ Boolean private
#allowed_method_name?(name) ⇒ Boolean private
#conversion_method?(method_name) ⇒ Boolean private
#correct_method(node, receiver) private
#correct_sym_method(to_method) private
#handle_as_symbol(node) private
#handle_conversion_method(node) private
#ignored_class?(name) ⇒ Boolean private
#ignored_classes private
#remove_parentheses(corrector, node) private
#top_receiver(node) private

`::RuboCop::Cop::AllowedPattern` - Included

#allowed_line?, #allowed_patterns, #cop_config_deprecated_methods_values, #cop_config_patterns_values,
#ignored_line?	Alias for AllowedPattern#allowed_line?.
#matches_allowed_pattern?,
#matches_ignored_pattern?	Alias for AllowedPattern#matches_allowed_pattern?.

`::RuboCop::Cop::AllowedMethods` - Included

#allowed_method?, #allowed_methods, #cop_config_allowed_methods, #cop_config_deprecated_values,
#ignored_method?	Alias for AllowedMethods#allowed_method?.

`::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 `add_offense` or `add_global_offense` Cops are discouraged to override this; instead pass your message directly.
#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, #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, #max_line_length,
#range_by_lines	Expand the given range to include all of any lines it covers.
#range_of_first_line, #surrounding_heredoc, #surrounding_percent_array

`::RuboCop::Cop::IgnoredNode` - Included

#ignore_node, #ignored_node?, #part_of_ignored_node?, #ignored_nodes

Constructor Details

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

Instance Method Details

#allow_receiver?(receiver) ⇒ `Boolean` (private)

[ GitHub ]

# File 'lib/rubocop/cop/lint/number_conversion.rb', line 165


def allow_receiver?(receiver)
  if receiver.numeric_type? || (receiver.send_type? &&
    (conversion_method?(receiver.method_name) ||
    allowed_method_name?(receiver.method_name)))
    true
  elsif (receiver = top_receiver(receiver))
    receiver.const_type? && ignored_class?(receiver.const_name)
  else
    false
  end
end

#allowed_method_name?(name) ⇒ `Boolean` (private)

[ GitHub ]

# File 'lib/rubocop/cop/lint/number_conversion.rb', line 177


def allowed_method_name?(name)
  allowed_method?(name) || matches_allowed_pattern?(name)
end

#conversion_method?(method_name) ⇒ `Boolean` (private)

[ GitHub ]

# File 'lib/rubocop/cop/lint/number_conversion.rb', line 187


def conversion_method?(method_name)
  CONVERSION_METHODS.include?(method_name)
end

#correct_method(node, receiver) (private)

[ GitHub ]

# File 'lib/rubocop/cop/lint/number_conversion.rb', line 151


def correct_method(node, receiver)
  format(CONVERSION_METHOD_CLASS_MAPPING[node.method_name], number_object: receiver.source)
end

#correct_sym_method(to_method) (private)

[ GitHub ]

# File 'lib/rubocop/cop/lint/number_conversion.rb', line 155


def correct_sym_method(to_method)
  body = format(CONVERSION_METHOD_CLASS_MAPPING[to_method], number_object: 'i')
  "{ |i| #{body} }"
end

#handle_as_symbol(node) (private)

[ GitHub ]

# File 'lib/rubocop/cop/lint/number_conversion.rb', line 134


def handle_as_symbol(node)
  to_method_symbol(node) do |receiver, sym_node, to_method|
    next if receiver.nil? || !node.arguments.one?

    message = format(
      MSG,
      current: sym_node.source,
      corrected_method: correct_sym_method(to_method)
    )
    add_offense(node, message: message) do |corrector|
      remove_parentheses(corrector, node) if node.parenthesized?

      corrector.replace(sym_node, correct_sym_method(to_method))
    end
  end
end

#handle_conversion_method(node) (private)

[ GitHub ]

# File 'lib/rubocop/cop/lint/number_conversion.rb', line 115


def handle_conversion_method(node)
  to_method(node) do |receiver, to_method|
    next if receiver.nil? || allow_receiver?(receiver)

    message = format(
      MSG,
      current: "#{receiver.source}.#{to_method}",
      corrected_method: correct_method(node, receiver)
    )
    add_offense(node, message: message) do |corrector|
      next if part_of_ignored_node?(node)

      corrector.replace(node, correct_method(node, node.receiver))

      ignore_node(node)
    end
  end
end

#ignored_class?(name) ⇒ `Boolean` (private)

[ GitHub ]

# File 'lib/rubocop/cop/lint/number_conversion.rb', line 195


def ignored_class?(name)
  ignored_classes.include?(name.to_s)
end

#ignored_classes (private)

[ GitHub ]

# File 'lib/rubocop/cop/lint/number_conversion.rb', line 191


def ignored_classes
  cop_config.fetch('IgnoredClasses', [])
end

#on_csend(node)

Alias for #on_send.

[ GitHub ]

# File 'lib/rubocop/cop/lint/number_conversion.rb', line 111


alias on_csend on_send

#on_send(node) Also known as: #on_csend

[ GitHub ]

# File 'lib/rubocop/cop/lint/number_conversion.rb', line 107


def on_send(node)
  handle_conversion_method(node)
  handle_as_symbol(node)
end

#remove_parentheses(corrector, node) (private)

[ GitHub ]

# File 'lib/rubocop/cop/lint/number_conversion.rb', line 160


def remove_parentheses(corrector, node)
  corrector.replace(node.loc.begin, ' ')
  corrector.remove(node.loc.end)
end

#to_method(node)

[ GitHub ]

# File 'lib/rubocop/cop/lint/number_conversion.rb', line 93


def_node_matcher :to_method, <<~PATTERN
  (call $_ ${#{METHODS}})
PATTERN

#to_method_symbol(node)

[ GitHub ]

# File 'lib/rubocop/cop/lint/number_conversion.rb', line 98


def_node_matcher :to_method_symbol, <<~PATTERN
  (call _ $_ ${
    {
      (sym ${#{METHODS}})
      (block_pass (sym ${#{METHODS}}))
    }
  } ...)
PATTERN

#top_receiver(node) (private)

[ GitHub ]

# File 'lib/rubocop/cop/lint/number_conversion.rb', line 181


def top_receiver(node)
  receiver = node
  receiver = receiver.receiver until receiver.receiver.nil?
  receiver
end

Class: RuboCop::Cop::Lint::NumberConversion

Overview

Constant Summary

::RuboCop::Cop::Base - Inherited

Class Attribute Summary

::RuboCop::Cop::AutoCorrector - Extended

::RuboCop::Cop::Base - Inherited

Class Method Summary

::RuboCop::Cop::Base - Inherited

::RuboCop::ExcludeLimit - Extended

Instance Attribute Summary

::RuboCop::Cop::Base - Inherited

::RuboCop::Cop::AutocorrectLogic - Included

Instance Method Summary

::RuboCop::Cop::AllowedPattern - Included

::RuboCop::Cop::AllowedMethods - Included

::RuboCop::Cop::Base - Inherited

::RuboCop::Cop::AutocorrectLogic - Included

::RuboCop::Cop::IgnoredNode - Included

Constructor Details

Instance Method Details

#allow_receiver?(receiver) ⇒ Boolean (private)

#allowed_method_name?(name) ⇒ Boolean (private)

#conversion_method?(method_name) ⇒ Boolean (private)

#correct_method(node, receiver) (private)

#correct_sym_method(to_method) (private)

#handle_as_symbol(node) (private)

#handle_conversion_method(node) (private)

#ignored_class?(name) ⇒ Boolean (private)

#ignored_classes (private)

#on_csend(node)

#on_send(node) Also known as: #on_csend

#remove_parentheses(corrector, node) (private)

#to_method(node)

#to_method_symbol(node)

#top_receiver(node) (private)

`::RuboCop::Cop::Base` - Inherited

`::RuboCop::Cop::AutoCorrector` - Extended

`::RuboCop::Cop::Base` - Inherited

`::RuboCop::Cop::Base` - Inherited

`::RuboCop::ExcludeLimit` - Extended

`::RuboCop::Cop::Base` - Inherited

`::RuboCop::Cop::AutocorrectLogic` - Included

`::RuboCop::Cop::AllowedPattern` - Included

`::RuboCop::Cop::AllowedMethods` - Included

`::RuboCop::Cop::Base` - Inherited

`::RuboCop::Cop::AutocorrectLogic` - Included

`::RuboCop::Cop::IgnoredNode` - Included

#allow_receiver?(receiver) ⇒ `Boolean` (private)

#allowed_method_name?(name) ⇒ `Boolean` (private)

#conversion_method?(method_name) ⇒ `Boolean` (private)

#ignored_class?(name) ⇒ `Boolean` (private)