lib/rubocop/cop/gemspec/duplicated_assignment.rb
# frozen_string_literal: true
module RuboCop
module Cop
module Gemspec
# An attribute assignment method calls should be listed only once
# in a gemspec.
#
# Assigning to an attribute with the same name using `spec.foo =` will be
# an unintended usage. On the other hand, duplication of methods such
# as `spec.requirements`, `spec.add_runtime_dependency`, and others are
# permitted because it is the intended use of appending values.
#
# @example
# # bad
# Gem::Specification.new do |spec|
# spec.name = 'rubocop'
# spec.name = 'rubocop2'
# end
#
# # good
# Gem::Specification.new do |spec|
# spec.name = 'rubocop'
# end
#
# # good
# Gem::Specification.new do |spec|
# spec.requirements << 'libmagick, v6.0'
# spec.requirements << 'A good graphics card'
# end
#
# # good
# Gem::Specification.new do |spec|
# spec.add_runtime_dependency('parallel', '~> 1.10')
# spec.add_runtime_dependency('parser', '>= 2.3.3.1', '< 3.0')
# end
class DuplicatedAssignment < Base
include RangeHelp
include GemspecHelp
MSG = '`%<assignment>s` method calls already given on line ' \
'%<line_of_first_occurrence>d of the gemspec.'
# @!method assignment_method_declarations(node)
def_node_search :assignment_method_declarations, <<~PATTERN
(send
(lvar #match_block_variable_name?) _ ...)
PATTERN
def on_new_investigation
return if processed_source.blank?
duplicated_assignment_method_nodes.each do |nodes|
nodes[1..].each do |node|
register_offense(node, node.method_name, nodes.first.first_line)
end
end
end
private
def match_block_variable_name?(receiver_name)
gem_specification(processed_source.ast) do |block_variable_name|
return block_variable_name == receiver_name
end
end
def duplicated_assignment_method_nodes
assignment_method_declarations(processed_source.ast)
.select(&:assignment_method?)
.group_by(&:method_name)
.values
.select { |nodes| nodes.size > 1 }
end
def register_offense(node, assignment, line_of_first_occurrence)
line_range = node.loc.column...node.loc.last_column
offense_location = source_range(processed_source.buffer, node.first_line, line_range)
message = format(
MSG,
assignment: assignment,
line_of_first_occurrence: line_of_first_occurrence
)
add_offense(offense_location, message: message)
end
end
end
end
end