Class: RuboCop::Cop::Style::RescueStandardError

Inherits:
Cop
  • Object
show all
Includes:
ConfigurableEnforcedStyle, RescueNode
Defined in:
lib/rubocop/cop/style/rescue_standard_error.rb

Overview

This cop checks for rescuing ‘StandardError`. There are two supported styles `implicit` and `explicit`. This cop will not register an offense if any error other than `StandardError` is specified.

Examples:

EnforcedStyle: implicit

# `implicit` will enforce using `rescue` instead of
# `rescue StandardError`.

# bad
begin
  foo
rescue StandardError
  bar
end

# good
begin
  foo
rescue
  bar
end

# good
begin
  foo
rescue OtherError
  bar
end

# good
begin
  foo
rescue StandardError, SecurityError
  bar
end

EnforcedStyle: explicit (default)

# `explicit` will enforce using `rescue StandardError`
# instead of `rescue`.

# bad
begin
  foo
rescue
  bar
end

# good
begin
  foo
rescue StandardError
  bar
end

# good
begin
  foo
rescue OtherError
  bar
end

# good
begin
  foo
rescue StandardError, SecurityError
  bar
end

Constant Summary collapse

MSG_IMPLICIT = 
'Omit the error class when rescuing ' \
'`StandardError` by itself.'.freeze
MSG_EXPLICIT = 
'Avoid rescuing without specifying ' \
'an error class.'.freeze

Constants included from Util

Util::ASGN_NODES, Util::BYTE_ORDER_MARK, Util::CONDITIONAL_NODES, Util::EQUALS_ASGN_NODES, Util::LITERAL_REGEX, Util::LOGICAL_OPERATOR_NODES, Util::MODIFIER_NODES, Util::OPERATOR_METHODS, Util::SHORTHAND_ASGN_NODES

Instance Attribute Summary

Attributes inherited from Cop

#config, #corrections, #offenses, #processed_source

Instance Method Summary collapse

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_detected, #style_parameter_name, #supported_styles, #unexpected_style_detected

Methods included from RescueNode

#investigate

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

#s

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?, effective_column, ends_its_line?, escape_string, first_part_of_call_chain, interpret_string_escapes, line_range, needs_escaping?, on_node, operator?, parentheses?, parenthesized_call?, precede?, range_between, range_by_whole_lines, range_with_surrounding_comma, range_with_surrounding_space, same_line?, source_range, strip_quotes, stripped_source_upto, symbol_without_quote?, to_string_literal, to_supported_styles, to_symbol_literal, within_node?

Methods included from PathUtil

absolute?, find_file_upwards, 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/rescue_standard_error.rb', line 106

def autocorrect(node)
  lambda do |corrector|
    case style
    when :implicit
      error = rescue_standard_error?(node)
      range = range_between(node.loc.keyword.end_pos,
                            error.loc.expression.end_pos)
      corrector.remove(range)
    when :explicit
      corrector.insert_after(node.loc.keyword, ' StandardError')
    end
  end
end

#on_resbody(node) ⇒ Object 



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# File 'lib/rubocop/cop/style/rescue_standard_error.rb', line 90

def on_resbody(node)
  return if rescue_modifier?(node)
  case style
  when :implicit
    rescue_standard_error?(node) do |error|
      add_offense(node,
                  location: node.loc.keyword.join(error.loc.expression),
                  message: MSG_IMPLICIT)
    end
  when :explicit
    rescue_without_error_class?(node) do
      add_offense(node, location: :keyword, message: MSG_EXPLICIT)
    end
  end
end