lib/rubocop/cop/style/hash_as_last_array_item.rb
# frozen_string_literal: true
module RuboCop
module Cop
module Style
# Checks for presence or absence of braces around hash literal as a last
# array item depending on configuration.
#
# NOTE: This cop will ignore arrays where all items are hashes, regardless of
# EnforcedStyle.
#
# @example EnforcedStyle: braces (default)
# # bad
# [1, 2, one: 1, two: 2]
#
# # good
# [1, 2, { one: 1, two: 2 }]
#
# # good
# [{ one: 1 }, { two: 2 }]
#
# @example EnforcedStyle: no_braces
# # bad
# [1, 2, { one: 1, two: 2 }]
#
# # good
# [1, 2, one: 1, two: 2]
#
# # good
# [{ one: 1 }, { two: 2 }]
class HashAsLastArrayItem < Base
include RangeHelp
include ConfigurableEnforcedStyle
extend AutoCorrector
def on_hash(node)
return if node.children.first&.kwsplat_type?
return unless (array = containing_array(node))
return unless last_array_item?(array, node) && explicit_array?(array)
if braces_style?
check_braces(node)
else
check_no_braces(node)
end
end
private
def containing_array(hash_node)
parent = hash_node.parent
parent if parent&.array_type?
end
def last_array_item?(array, node)
return false if array.child_nodes.all?(&:hash_type?)
array.children.last.equal?(node)
end
def explicit_array?(array)
# an implicit array cannot have an "unbraced" hash
array.square_brackets?
end
def check_braces(node)
return if node.braces?
add_offense(node, message: 'Wrap hash in `{` and `}`.') do |corrector|
corrector.wrap(node, '{', '}')
end
end
def check_no_braces(node)
return unless node.braces?
return if node.children.empty? # Empty hash cannot be "unbraced"
add_offense(node, message: 'Omit the braces around the hash.') do |corrector|
remove_last_element_trailing_comma(corrector, node.parent)
corrector.remove(node.loc.begin)
corrector.remove(node.loc.end)
end
end
def braces_style?
style == :braces
end
def remove_last_element_trailing_comma(corrector, node)
range = range_with_surrounding_space(
node.children.last.source_range,
side: :right
).end.resize(1)
corrector.remove(range) if range.source == ','
end
end
end
end
end