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# frozen_string_literal: true
module RuboCop
module Cop
# Ensures a line break after guard clauses.
#
# @example
# # bad
# return unless condition
# do_stuff
#
# # good
# return unless condition
#
# do_stuff
#
# # bad
# raise if condition
# do_stuff
#
# # good
# raise if condition
#
# do_stuff
#
# Multiple guard clauses are allowed without
# line break.
#
# # good
# return unless condition_a
# return unless condition_b
#
# do_stuff
#
# Guard clauses in case statement are allowed without
# line break.
#
# # good
# case model
# when condition_a
# return true unless condition_b
# when
# ...
# end
#
# Guard clauses before end are allowed without
# line break.
#
# # good
# if condition_a
# do_something
# else
# do_something_else
# return unless condition
# end
#
# do_something_more
class LineBreakAfterGuardClauses < RuboCop::Cop::Cop
MSG = 'Add a line break after guard clauses'
def_node_matcher :guard_clause_node?, <<-PATTERN
[{(send nil? {:raise :fail :throw} ...) return break next} single_line?]
PATTERN
def on_if(node)
return unless node.single_line?
return unless guard_clause?(node)
return if next_line(node).blank? || clause_last_line?(next_line(node)) || guard_clause?(next_sibling(node))
add_offense(node, :expression, MSG)
end
def autocorrect(node)
lambda do |corrector|
corrector.insert_after(node.loc.expression, "\n")
end
end
private
def guard_clause?(node)
return false unless node.if_type?
guard_clause_node?(node.if_branch)
end
def next_sibling(node)
node.parent.children[node.sibling_index + 1]
end
def next_line(node)
processed_source[node.loc.line]
end
def clause_last_line?(line)
line =~ /^\s*(?:end|elsif|else|when|rescue|ensure)/
end
end
end
end