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# frozen_string_literal: true
require 'spec_helper'
RSpec.describe('RefCall scanning') do
# Traditional numerical group back-reference.
# For non-matched cases see ./escapes_spec.rb
include_examples 'scan', '(abc)\1' , 3 => [:backref, :number, '\1', 5, 7]
# They can have two or more digits:
# "#{[*2..101].join}101"[/#{(2..101).map { |n| "(#{n})" }.join}\K\100/] # => '101'
include_examples 'scan', '(((((((((())))))))))\10',
-1 => [:backref, :number, '\10', 20, 23]
include_examples 'scan', "#{[*1..100].map { |n| "(#{n})" }.join}\\100",
-1 => [:backref, :number, '\100', 392, 396]
# Double digit escapes are treated as backref as soon as a fitting group is open:
# "\10"[/((((((((((\10))))))))))/] # => nil
include_examples 'scan', '((((((((((\10))))))))))',
10 => [:backref, :number, '\10', 10, 13]
# Group back-references, named, numbered, and relative
#
# NOTE: only \g supports forward-looking references using '+', e.g. \g<+1>
# refers to the next group, but \k<+1> refers to a group named '+1'.
# Inversely, only \k supports addition or subtraction of a recursion level.
# E.g. \k<x+0> refers to a group named 'x' at the current recursion level,
# but \g<x+0> refers to a a group named 'x+0'.
#
include_examples 'scan', '(?<X>abc)\k<X>', 3 => [:backref, :name_ref_ab, '\k<X>', 9, 14]
include_examples 'scan', "(?<X>abc)\\k'X'", 3 => [:backref, :name_ref_sq, "\\k'X'", 9, 14]
include_examples 'scan', '(?<+1>abc)\k<+1>', 3 => [:backref, :name_ref_ab, '\k<+1>', 10, 16]
include_examples 'scan', "(?<+1>abc)\\k'+1'", 3 => [:backref, :name_ref_sq, "\\k'+1'", 10, 16]
include_examples 'scan', '(abc)\k<1>', 3 => [:backref, :number_ref_ab, '\k<1>', 5, 10]
include_examples 'scan', "(abc)\\k'1'", 3 => [:backref, :number_ref_sq, "\\k'1'", 5, 10]
include_examples 'scan', "(abc)\\k'001'", 3 => [:backref, :number_ref_sq, "\\k'001'", 5, 12]
include_examples 'scan', '(abc)\k<-1>', 3 => [:backref, :number_rel_ref_ab, '\k<-1>', 5, 11]
include_examples 'scan', "(abc)\\k'-1'", 3 => [:backref, :number_rel_ref_sq, "\\k'-1'", 5, 11]
include_examples 'scan', '(abc)\k<-001>', 3 => [:backref, :number_rel_ref_ab, '\k<-001>', 5, 13]
# Sub-expression invocation, named, numbered, and relative
include_examples 'scan', '(?<X>abc)\g<X>', 3 => [:backref, :name_call_ab, '\g<X>', 9, 14]
include_examples 'scan', "(?<X>abc)\\g'X'", 3 => [:backref, :name_call_sq, "\\g'X'", 9, 14]
include_examples 'scan', '(?<X>abc)\g<X-1>', 3 => [:backref, :name_call_ab, '\g<X-1>', 9, 16]
include_examples 'scan', "(?<X>abc)\\g'X-1'", 3 => [:backref, :name_call_sq, "\\g'X-1'", 9, 16]
include_examples 'scan', '(abc)\g<1>', 3 => [:backref, :number_call_ab, '\g<1>', 5, 10]
include_examples 'scan', "(abc)\\g'1'", 3 => [:backref, :number_call_sq, "\\g'1'", 5, 10]
include_examples 'scan', '(abc)\g<001>', 3 => [:backref, :number_call_ab, '\g<001>', 5, 12]
include_examples 'scan', 'a(b|\g<0>)', 4 => [:backref, :number_call_ab, '\g<0>', 4, 9]
include_examples 'scan', "a(b|\\g'0')", 4 => [:backref, :number_call_sq, "\\g'0'", 4, 9]
include_examples 'scan', '(abc)\g<-1>', 3 => [:backref, :number_rel_call_ab, '\g<-1>', 5, 11]
include_examples 'scan', "(abc)\\g'-1'", 3 => [:backref, :number_rel_call_sq, "\\g'-1'", 5, 11]
include_examples 'scan', '(abc)\g<-001>', 3 => [:backref, :number_rel_call_ab, '\g<-001>', 5, 13]
include_examples 'scan', '\g<+1>(abc)', 0 => [:backref, :number_rel_call_ab, '\g<+1>', 0, 6]
include_examples 'scan', "\\g'+1'(abc)", 0 => [:backref, :number_rel_call_sq, "\\g'+1'", 0, 6]
# Group back-references, with recursion level
include_examples 'scan', '(?<X>abc)\k<X-0>', 3 => [:backref, :name_recursion_ref_ab, '\k<X-0>', 9, 16]
include_examples 'scan', "(?<X>abc)\\k'X-0'", 3 => [:backref, :name_recursion_ref_sq, "\\k'X-0'", 9, 16]
include_examples 'scan', '(abc)\k<1-0>', 3 => [:backref, :number_recursion_ref_ab, '\k<1-0>', 5, 12]
include_examples 'scan', "(abc)\\k'1-0'", 3 => [:backref, :number_recursion_ref_sq, "\\k'1-0'", 5, 12]
include_examples 'scan', '(abc)\k<+1-0>', 3 => [:backref, :name_recursion_ref_ab, '\k<+1-0>', 5, 13]
include_examples 'scan', "(abc)\\k'+1-0'", 3 => [:backref, :name_recursion_ref_sq, "\\k'+1-0'", 5, 13]
end
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