Class: RuboCop::Cop::Style::HashLookupMethod

Inherits:

Base

• Object
• Base
• RuboCop::Cop::Style::HashLookupMethod

Extended by:

AutoCorrector

Includes:

ConfigurableEnforcedStyle

Defined in:

lib/rubocop/cop/style/hash_lookup_method.rb

Overview

Enforces the use of either ‘Hash#[]` or `Hash#fetch` for hash lookup.

This cop can be configured to prefer either bracket-style ([]) or fetch-style lookup. It is disabled by default.

When enforcing fetch style, only single-argument bracket access is flagged. When enforcing brackets style, only fetch calls with a single key argument are flagged (not those with default values or blocks).

Examples:

EnforcedStyle: brackets (default)

# bad
hash.fetch(key)

# good
hash[key]

# good - fetch with default value is allowed
hash.fetch(key, default)

# good - fetch with block is allowed
hash.fetch(key) { default }

EnforcedStyle: fetch

# bad
hash[key]

# good
hash.fetch(key)

Constant Summary

BRACKET_MSG =

'Use `Hash#[]` instead of `Hash#fetch`.'

FETCH_MSG =

'Use `Hash#fetch` instead of `Hash#[]`.'

RESTRICT_ON_SEND =

i[[] fetch].freeze

Instance Attribute Summary

Attributes inherited from Base

#config, #processed_source

Instance Method Summary

• #on_send(node) ⇒ Object (also: #on_csend)

Methods included from AutoCorrector

support_autocorrect?

Methods included from ConfigurableEnforcedStyle

#alternative_style, #alternative_styles, #ambiguous_style_detected, #correct_style_detected, #detected_style, #detected_style=, #no_acceptable_style!, #no_acceptable_style?, #opposite_style_detected, #style, #style_configured?, #style_detected, #style_parameter_name, #supported_styles, #unexpected_style_detected

Methods inherited from Base

#active_support_extensions_enabled?, #add_global_offense, #add_offense, #always_autocorrect?, autocorrect_incompatible_with, badge, #begin_investigation, #callbacks_needed, callbacks_needed, #config_to_allow_offenses, #config_to_allow_offenses=, #contextual_autocorrect?, #cop_config, #cop_name, cop_name, department, documentation_url, exclude_from_registry, #excluded_file?, #external_dependency_checksum, inherited, #initialize, #inspect, joining_forces, lint?, match?, #message, #offenses, #on_investigation_end, #on_new_investigation, #on_other_file, #parse, #parser_engine, #ready, #relevant_file?, requires_gem, #string_literals_frozen_by_default?, support_autocorrect?, support_multiple_source?, #target_gem_version, #target_rails_version, #target_ruby_version

Methods included from ExcludeLimit

#exclude_limit

Methods included from AutocorrectLogic

#autocorrect?, #autocorrect_enabled?, #autocorrect_requested?, #autocorrect_with_disable_uncorrectable?, #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_send(node) ⇒ Object Also known as: on_csend

# File 'lib/rubocop/cop/style/hash_lookup_method.rb', line 53

def on_send(node)
  if offense_for_brackets?(node)
    add_offense(node.loc.selector, message: BRACKET_MSG) do |corrector|
      correct_fetch_to_brackets(corrector, node)
    end
  elsif offense_for_fetch?(node)
    add_offense(node, message: FETCH_MSG) do |corrector|
      correct_brackets_to_fetch(corrector, node)
    end
  end
end