Class: RuboCop::Cop::Lint::LiteralAssignmentInCondition

Inherits:
Base
  • Object
show all
Defined in:
lib/rubocop/cop/lint/literal_assignment_in_condition.rb

Overview

Checks for literal assignments in the conditions of ‘if`, `while`, and `until`. It emulates the following Ruby warning:

source,console

$ ruby -we ‘if x = true; end’ -e:1: warning: found ‘= literal’ in conditional, should be ==

As a lint cop, it cannot be determined if ‘==` is appropriate as intended, therefore this cop does not provide autocorrection.

Examples:


# bad
if x = 42
  do_something
end

# good
if x == 42
  do_something
end

# good
if x = y
  do_something
end

Constant Summary collapse

MSG = 
"Don't use literal assignment `= %<literal>s` in conditional, " \
'should be `==` or non-literal operand.'

Constants inherited from Base

Base::RESTRICT_ON_SEND

Instance Attribute Summary

Attributes inherited from Base

#config, #processed_source

Instance Method Summary collapse

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, support_autocorrect?, support_multiple_source?, #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_if(node) ⇒ Object Also known as: on_while, on_until 



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# File 'lib/rubocop/cop/lint/literal_assignment_in_condition.rb', line 39

def on_if(node)
  traverse_node(node.condition) do |asgn_node|
    next unless asgn_node.loc.operator

    rhs = asgn_node.to_a.last
    next if !all_literals?(rhs) || parallel_assignment_with_splat_operator?(rhs)

    range = offense_range(asgn_node, rhs)

    add_offense(range, message: format(MSG, literal: rhs.source))
  end
end