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Beware the Dreaded Dead End!!! By @schneems

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Beware the Dreaded Dead End!!! By @schneems

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> # <= routes.rb:121: syntax error, unexpected end-of-input, expecting `end’ Rails.application.routes.draw do constraints -> { Rails.application.config.non_production } do namespace :foo do resource :bar end end constraints -> { Rails.application.config.non_production } do namespace :bar do resource :baz end end namespace :admin do resource :session match "/foobar(*path)", via: :all, to: redirect { |_params, req| uri = URI(req.path.gsub("foobar", "foobaz")) uri.query = req.query_string.presence uri.to_s } end

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> Rails.application.routes.draw do constraints -> { Rails.application.config.non_production } do namespace :foo do resource :bar end end constraints -> { Rails.application.config.non_production } do namespace :bar do resource :baz end end namespace :admin do resource :session match "/foobar(*path)", via: :all, to: redirect { |_params, req| uri = URI(req.path.gsub("foobar", "foobaz")) uri.query = req.query_string.presence uri.to_s } end # <= routes.rb:121: syntax error, unexpected end-of-input, expecting `end’

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> RSpec.describe Cutlass::BashResult do it "preserves stdout, stderr, and status" stdout = SecureRandom.hex(16) stderr = SecureRandom.hex(16) status = 0 result = BashResult.new( stdout: stdout, stderr: stderr, status: status ) expect(result.stdout).to eq(stdout) expect(result.stderr).to eq(stderr) expect(result.status).to eq(status) end end # <= result_spec:19 syntax error, unexpected end-of-input, expecting `end’

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🤔

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> 3 module Cutlass 4 RSpec.describe Cutlass::BashResult do ❯ 5 it "preserves stdout, stderr, and status" ❯ 19 end 21 it "success?" do 52 end 53 end 54 end This code has an unmatched `end`. Ensure that all `end` lines in your code have a matching syntax keyword (`def`, `do`, etc.)

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>

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> # frozen_string_literal: true module Cutlass RSpec.describe Cutlass::BashResult do it "preserves stdout, stderr, and status" stdout = SecureRandom.hex(16) stderr = SecureRandom.hex(16) status = 0 result = BashResult.new( stdout: stdout, stderr: stderr, status: status ) expect(result.stdout).to eq(stdout) expect(result.stderr).to eq(stderr) expect(result.status).to eq(status) end end end # <= result_spec:19 syntax error, unexpected end-of-input, expecting `end’

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> 3 module Cutlass 4 RSpec.describe Cutlass::BashResult do ❯ 5 it "preserves stdout, stderr, and status" ❯ 19 end 21 it "success?" do 52 end 53 end 54 end

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0 25 50 75 100 April May June July (I did not do a study)

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(This is a lie) -30 -15 0 15 30 45 60 April May June July August

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(Also a lie) 7% 8% 11% 11% 31% 32%

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🥰

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$ gem install dead_end

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> 3 module Cutlass 4 RSpec.describe Cutlass::BashResult do ❯ 5 it "preserves stdout, stderr, and status" ❯ 19 end 21 it "success?" do 52 end 53 end 54 end DeadEnd: Unmatched `end` detected

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> 1 module Cutlass 2 RSpec.describe Cutlass::BashResult do ❯ 3 it "preserves stdout, stderr, and status" do 5 it "success?" do 6 end 7 end 8 end DeadEnd: Missing `end` detected

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> 1 class Cat 2 def to_json ❯ 3 hash = { ❯ 4 name: name, ❯ 5 fur_color: fur_color, ❯ 6 type: 'Cat', ❯ 7 better_than_dog: false ❯ 8 hash.to_json 9 end 10 end DeadEnd: Unmatched `}` character detected

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> 1 class Animal 2 def self.ones_my_three_year_old_likes ❯ 3 array = ❯ 4 Dog.new, ❯ 5 Lion.new, ❯ 6 Tiger.new, ❯ 7 Aligator.new, ❯ 8 ] 10 return array 11 end 12 end DeadEnd: Unmatched `[` detected

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> 1 class Cat 2 def meow ❯ 3 Animal.call do |a ❯ 5 end 6 end 7 end DeadEnd: Unmatched `|` character detected

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> 1 class Cat 2 def meow ❯ 3 Animal.call do |a ❯ 5 end 6 end 7 end DeadEnd: Unmatched `|` character detected ? ? ?

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$ gem install dead_end

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Syntax errors

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Lexing & Parsing

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AI

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dead_end

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Internals

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🤚

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@schneems

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@schneems

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📕 How to Open Source

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Heroku

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Heroku

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NoMemoryError ScriptError LoadError SyntaxError SecurityError SignalException KeyError StandardError ArgumentError EncodingError IOError EOFError I am Exceptional

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> Dir.chhhdir("/tmp") do puts `ls` end

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> Dir.chhhdir("/tmp") do puts `ls` end # unde fi ned method `chhhdir' for # Dir:Class (NoMethodError ) # Did you mean? chdir

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>

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require 'bundler' require 'date' require 'optparse' require 'ostruct' require 'shellwords' class Rexe VERSION = '1.5.1' PROJECT_URL = 'https://github.com/keithrbennett/rexe' module Helpers # Try executing code. If error raised, print message (but not stack trace) & exit -1. def try begin

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end def bundler_run(&block) # This used to be an unconditional call to with_clean_env but that method is now deprecated: # [DEPRECATED] `Bundler.with_clean_env` has been deprecated in favor of `Bundler.with_unbundled_env`. # If you instead want the environment before bundler was originally loaded, # use `Bundler.with_original_env` if Bundler.respond_to?(:with_unbundled_env) Bundler.with_unbundled_env { block.call } else Bundler.with_clean_env { block.call } end end bundler_run { Rexe::Main.new.call }

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if / end unless / end while / end until / end def / end for / end begin / end class / end module / end do / end

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> Dir.chdir("lol") puts `ls` end ☠☠☠

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> Dir.chdir("lol") puts `ls` end ??

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> Dir.chdir("/tmp") Dir.chdir("lol") do puts `ls` end

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> def bark puts "woof" end bark() # => "woof"

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> def bark puts "woof" end bark do puts "not a syntax error" end # => "woof"

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> expect(WebMock).to have_requested( :post, "localhost:#{port}" ). end $ ruby -wc scratch.rb Syntax OK

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📓

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Lexing & Parsing

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"hello world" Ripper.lex >

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"hello world" Ripper.lex [ [[1, 0], :on_tstring_beg, "\"", BEG], [[1, 1], :on_tstring_content, "hello world", BEG], [[1, 12], :on_tstring_end, "\"", END], [[1, 13], :on_nl, "\n", BEG] ] >

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[ [[1, 0], :on_tstring_beg, "\"", BEG], [[1, 1], :on_tstring_content, "hello world", BEG], [[1, 12], :on_tstring_end, "\"", END], [[1, 13], :on_nl, "\n", BEG] ]

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[ [[1, 0], :on_tstring_beg, "\"", BEG], [[1, 1], :on_tstring_content, "hello world", BEG], [[1, 12], :on_tstring_end, "\"", END], [[1, 13], :on_nl, "\n", BEG] ]

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[ [[1, 0], :on_tstring_beg, "\"", BEG], [[1, 1], :on_tstring_content, "hello world", BEG], [[1, 12], :on_tstring_end, "\"", END], [[1, 13], :on_nl, "\n", BEG] ]

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while b != 0 if a > b a = a - b else b = b - a end end return a Ripper.parse

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while b != 0 # if a > b a = a - b else b = b - a end end return a Ripper.parse :(

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🤔

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while b != 0 # if a > b a = a - b else b = b - a end end return a Ripper.parse :(

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while b != 0 # if a > b # a = a - b # else # b = b - a # end end return a Ripper.parse :)

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while b != 0 # if a > b # a = a - b # else # b = b - a # end end return a Ripper.parse :)

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AI

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Artificial Intelligence Algorithm

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Artificial Intelligence Algorithm

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Pathfinding Credit: Factorio 'New pathfinding algorithm'

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Credit @redblobgames: Introduction to the A-star Algorithm

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Pathfinding Credit: Factorio 'New pathfinding algorithm'

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Tree
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 "Reti Draw" Endgame Chess problem by Richard Reti (1921)

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Tree
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 BOTVINNIK, M.M. (1984). "Computers in Chess Solving Inexact Search Problems"

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Non-optimal Play

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Checkmate Black

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Optimal Draw Play

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Draw

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Tree
 Search
 BOTVINNIK, M.M. (1984). "Computers in Chess Solving Inexact Search Problems"

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AI ~ Search

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while b != 0 if a > b a = a - b else b = b - a end end return a Ripper.parse

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while b != 0 # if a > b a = a - b else b = b - a end end return a Ripper.parse

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❌🌳💔

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> Dir.chdir("/tmp") Dir.chdir("lol") end do??? do??? puts `ls`

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> Dir.chdir("/tmp") Dir.chdir("lol") end do puts `ls`🥰

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while b != 0 # if a > b # a = a - b # else # b = b - a # end end return a Ripper.parse

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🌳 ❌ 💔

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demo

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module SyntaxErrorSearch # Used for formatting invalid blocks class DisplayInvalidBlocks attr_reader :filename def initialize(block_array, io: $stderr, filename: nil) @filename = filename @io = io @blocks = block_array @lines = @blocks.map(&:lines).flatten @digit_count = @lines.last.line_number.to_s.length @code_lines = @blocks.first.code_lines @invalid_line_hash = @lines.each_with_object({}) {|line, h| h[line] = true} end def call 64: syntax error, unexpected end-of-input, expecting `end' 📕 ❌

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51 if line.empty? 52 "#{number.to_s}#{line}" 53 else 54 string = String.new 55 string << "\e[1;3m" if @invalid_line_hash[line] # Bold, italics 56 string << "#{number.to_s} " 57 string << line.to_s 58 string << "\e[0m" 59 string 60 end 61 end.join 62 end 63 end 64 end

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50 number = line.line_number.to_s.rjust(@digit_count) 51 if line.empty? 52 "#{number.to_s}#{line}" 53 else 54 string = String.new 55 string << "\e[1;3m" if @invalid_line_hash[line] # Bold, italics 56 string << "#{number.to_s} " 57 string << line.to_s 58 string << "\e[0m" ❯ 59 string 60 end 61 end.join 62 end 63 end 64 end

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50 number = line.line_number.to_s.rjust(@digit_count) 51 if line.empty? 52 "#{number.to_s}#{line}" 53 else 54 string = String.new 55 string << "\e[1;3m" if @invalid_line_hash[line] # Bold, italics 56 string << "#{number.to_s} " 57 string << line.to_s ❯ 58 string << "\e[0m" ❯ 59 string 60 end 61 end.join 62 end 63 end 64 end

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50 number = line.line_number.to_s.rjust(@digit_count) 51 if line.empty? 52 "#{number.to_s}#{line}" 53 else 54 string = String.new 55 string << "\e[1;3m" if @invalid_line_hash[line] # Bold, italics 56 string << "#{number.to_s} " ❯ 57 string << line.to_s ❯ 58 string << "\e[0m" ❯ 59 string 60 end 61 end.join 62 end 63 end 64 end

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50 number = line.line_number.to_s.rjust(@digit_count) 51 if line.empty? 52 "#{number.to_s}#{line}" 53 else 54 string = String.new 55 string << "\e[1;3m" if @invalid_line_hash[line] # Bold, italics ❯ 56 string << "#{number.to_s} " ❯ 57 string << line.to_s ❯ 58 string << "\e[0m" ❯ 59 string 60 end 61 end.join 62 end 63 end 64 end

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50 number = line.line_number.to_s.rjust(@digit_count) 51 if line.empty? 52 "#{number.to_s}#{line}" 53 else 54 string = String.new ❯ 55 string << "\e[1;3m" if @invalid_line_hash[line] # Bold, italics ❯ 56 string << "#{number.to_s} " ❯ 57 string << line.to_s ❯ 58 string << "\e[0m" ❯ 59 string 60 end 61 end.join 62 end 63 end 64 end

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50 number = line.line_number.to_s.rjust(@digit_count) 51 if line.empty? 52 "#{number.to_s}#{line}" 53 else ❯ 54 string = String.new ❯ 55 string << "\e[1;3m" if @invalid_line_hash[line] # Bold, italics ❯ 56 string << "#{number.to_s} " ❯ 57 string << line.to_s ❯ 58 string << "\e[0m" ❯ 59 string 60 end 61 end.join 62 end 63 end 64 end

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50 number = line.line_number.to_s.rjust(@digit_count) 51 if line.empty? 52 "#{number.to_s}#{line}" 53 else 60 end 61 end.join 62 end 63 end 64 end 📕 ❌

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42 string << code_with_lines 43 string << "```\n" 44 string 45 end 46 47 def code_with_lines 48 @code_lines.map do |line| 49 next if line.hidden? 50 number = line.line_number.to_s.rjust(@digit_count) 51 if line.empty? ❯ 52 "#{number.to_s}#{line}" 53 else 60 end 61 end.join 62 end 63 end 64 end

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42 string << code_with_lines 43 string << "```\n" 44 string 45 end 46 47 def code_with_lines 48 @code_lines.map do |line| 49 next if line.hidden? 50 number = line.line_number.to_s.rjust(@digit_count) 51 if line.empty? 53 else 60 end 61 end.join 62 end 63 end 64 end 📕 ❌

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42 string << code_with_lines 43 string << "```\n" 44 string 45 end 46 47 def code_with_lines 48 @code_lines.map do |line| 49 next if line.hidden? 50 number = line.line_number.to_s.rjust(@digit_count) ❯ 51 if line.empty? ❯ 53 else ❯ 60 end 61 end.join 62 end 63 end 64 end

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42 string << code_with_lines 43 string << "```\n" 44 string 45 end 46 47 def code_with_lines 48 @code_lines.map do |line| 49 next if line.hidden? 50 number = line.line_number.to_s.rjust(@digit_count) 61 end.join 62 end 63 end 64 end 📕 ❌

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42 string << code_with_lines 43 string << "```\n" 44 string 45 end 46 47 def code_with_lines 48 @code_lines.map do |line| ❯ 49 next if line.hidden? ❯ 50 number = line.line_number.to_s.rjust(@digit_count) 61 end.join 62 end 63 end 64 end

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42 string << code_with_lines 43 string << "```\n" 44 string 45 end 46 47 def code_with_lines 48 @code_lines.map do |line| 61 end.join 62 end 63 end 64 end 📕 ❌

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42 string << code_with_lines 43 string << "```\n" 44 string 45 end 46 47 def code_with_lines ❯ 48 @code_lines.map do |line| ❯ 61 end.join 62 end 63 end 64 end

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42 string << code_with_lines 43 string << "```\n" 44 string 45 end 46 47 def code_with_lines 62 end 63 end 64 end 📕 ❌

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42 string << code_with_lines 43 string << "```\n" 44 string 45 end 46 ❯ 47 def code_with_lines ❯ 62 end 63 end 64 end

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40 string << "```\n" 41 string << "#".rjust(@digit_count) + " filename: #{filename}\n\n" if filename 42 string << code_with_lines 43 string << "```\n" 44 string 45 end 46 63 end 64 end 📕 ❌

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13 14 @invalid_line_hash = @lines.each_with_object({}) {|line, h| h[line] = true} 15 end 16 35 36 def filename 37 38 def code_with_filename 39 string = String.new("") 40 string << "```\n" 41 string << "#".rjust(@digit_count) + " filename: #{filename}\n\n" if filename 42 string << code_with_lines 43 string << "```\n" 44 string 45 end 46 63 end 64 end

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13 14 @invalid_line_hash = @lines.each_with_object({}) {|line, h| h[line] = true} 15 end 16 35 36 def filename 37 38 def code_with_filename 39 string = String.new("") 40 string << "```\n" 41 string << "#".rjust(@digit_count) + " filename: #{filename}\n\n" if filename 42 string << code_with_lines 43 string << "```\n" ❯ 44 string 45 end 46 63 end 64 end

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13 14 @invalid_line_hash = @lines.each_with_object({}) {|line, h| h[line] = true} 15 end 16 35 36 def filename 37 38 def code_with_filename 39 string = String.new("") 40 string << "```\n" 41 string << "#".rjust(@digit_count) + " filename: #{filename}\n\n" if filename 42 string << code_with_lines ❯ 43 string << "```\n" ❯ 44 string 45 end 46 63 end 64 end

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13 14 @invalid_line_hash = @lines.each_with_object({}) {|line, h| h[line] = true} 15 end 16 35 36 def filename 37 38 def code_with_filename 39 string = String.new("") 40 string << "```\n" 41 string << "#".rjust(@digit_count) + " filename: #{filename}\n\n" if filename ❯ 42 string << code_with_lines ❯ 43 string << "```\n" ❯ 44 string 45 end 46 63 end 64 end

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13 14 @invalid_line_hash = @lines.each_with_object({}) {|line, h| h[line] = true} 15 end 16 35 36 def filename 37 38 def code_with_filename 39 string = String.new("") 40 string << "```\n" ❯ 41 string << "#".rjust(@digit_count) + " filename: #{filename}\n\n" if filename ❯ 42 string << code_with_lines ❯ 43 string << "```\n" ❯ 44 string 45 end 46 63 end 64 end

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13 14 @invalid_line_hash = @lines.each_with_object({}) {|line, h| h[line] = true} 15 end 16 35 36 def filename 37 38 def code_with_filename 39 string = String.new("") ❯ 40 string << "```\n" ❯ 41 string << "#".rjust(@digit_count) + " filename: #{filename}\n\n" if filename ❯ 42 string << code_with_lines ❯ 43 string << "```\n" ❯ 44 string 45 end 46 63 end 64 end

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13 14 @invalid_line_hash = @lines.each_with_object({}) {|line, h| h[line] = true} 15 end 16 35 36 def filename 37 38 def code_with_filename ❯ 39 string = String.new("") ❯ 40 string << "```\n" ❯ 41 string << "#".rjust(@digit_count) + " filename: #{filename}\n\n" if filename ❯ 42 string << code_with_lines ❯ 43 string << "```\n" ❯ 44 string 45 end 46 63 end 64 end

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13 14 @invalid_line_hash = @lines.each_with_object({}) {|line, h| h[line] = true} 15 end 16 35 36 def filename 37 38 def code_with_filename 45 end 46 63 end 64 end 📕 ❌

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1 module SyntaxErrorSearch 3 class DisplayInvalidBlocks 4 attr_reader :filename 5 6 def initialize(block_array, io: $stderr, filename: nil) 7 @filename = filename 8 @io = io 9 @blocks = block_array 10 @lines = @blocks.map(&:lines).flatten 11 @digit_count = @lines.last.line_number.to_s.length 12 @code_lines = @blocks.first.code_lines 13 14 @invalid_line_hash = @lines.each_with_object({}) {|line, h| h[line] = true} 15 end 16 35 36 def filename 37

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1 module SyntaxErrorSearch 3 class DisplayInvalidBlocks 4 attr_reader :filename 5 6 def initialize(block_array, io: $stderr, filename: nil) 7 @filename = filename 8 @io = io 9 @blocks = block_array 10 @lines = @blocks.map(&:lines).flatten 11 @digit_count = @lines.last.line_number.to_s.length 12 @code_lines = @blocks.first.code_lines 13 ❯ 14 @invalid_line_hash = @lines.each_with_object({}) {|line, h| h[line] = true} 15 end 16 35 36 def filename 37

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1 module SyntaxErrorSearch 3 class DisplayInvalidBlocks 4 attr_reader :filename 5 6 def initialize(block_array, io: $stderr, filename: nil) 7 @filename = filename 8 @io = io 9 @blocks = block_array 10 @lines = @blocks.map(&:lines).flatten 11 @digit_count = @lines.last.line_number.to_s.length ❯ 12 @code_lines = @blocks.first.code_lines ❯ 13 ❯ 14 @invalid_line_hash = @lines.each_with_object({}) {|line, h| h[line] = true} 15 end 16 35 36 def filename

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1 module SyntaxErrorSearch 3 class DisplayInvalidBlocks 4 attr_reader :filename 5 6 def initialize(block_array, io: $stderr, filename: nil) 7 @filename = filename 8 @io = io 9 @blocks = block_array 10 @lines = @blocks.map(&:lines).flatten ❯ 11 @digit_count = @lines.last.line_number.to_s.length ❯ 12 @code_lines = @blocks.first.code_lines ❯ 13 ❯ 14 @invalid_line_hash = @lines.each_with_object({}) {|line, h| h[line] = true} 15 end 16 35 36 def filename

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1 module SyntaxErrorSearch 3 class DisplayInvalidBlocks 4 attr_reader :filename 5 6 def initialize(block_array, io: $stderr, filename: nil) 7 @filename = filename 8 @io = io 9 @blocks = block_array ❯ 10 @lines = @blocks.map(&:lines).flatten ❯ 11 @digit_count = @lines.last.line_number.to_s.length ❯ 12 @code_lines = @blocks.first.code_lines ❯ 13 ❯ 14 @invalid_line_hash = @lines.each_with_object({}) {|line, h| h[line] = true} 15 end 16 35 36 def filename

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1 module SyntaxErrorSearch 3 class DisplayInvalidBlocks 4 attr_reader :filename 5 6 def initialize(block_array, io: $stderr, filename: nil) 7 @filename = filename 8 @io = io ❯ 9 @blocks = block_array ❯ 10 @lines = @blocks.map(&:lines).flatten ❯ 11 @digit_count = @lines.last.line_number.to_s.length ❯ 12 @code_lines = @blocks.first.code_lines ❯ 13 ❯ 14 @invalid_line_hash = @lines.each_with_object({}) {|line, h| h[line] = true} 15 end 16 35 36 def filename

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1 module SyntaxErrorSearch 3 class DisplayInvalidBlocks 4 attr_reader :filename 5 6 def initialize(block_array, io: $stderr, filename: nil) 7 @filename = filename ❯ 8 @io = io ❯ 9 @blocks = block_array ❯ 10 @lines = @blocks.map(&:lines).flatten ❯ 11 @digit_count = @lines.last.line_number.to_s.length ❯ 12 @code_lines = @blocks.first.code_lines ❯ 13 ❯ 14 @invalid_line_hash = @lines.each_with_object({}) {|line, h| h[line] = true} 15 end 16 35 36 def filename

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1 module SyntaxErrorSearch 3 class DisplayInvalidBlocks 4 attr_reader :filename 5 6 def initialize(block_array, io: $stderr, filename: nil) ❯ 7 @filename = filename ❯ 8 @io = io ❯ 9 @blocks = block_array ❯ 10 @lines = @blocks.map(&:lines).flatten ❯ 11 @digit_count = @lines.last.line_number.to_s.length ❯ 12 @code_lines = @blocks.first.code_lines ❯ 13 ❯ 14 @invalid_line_hash = @lines.each_with_object({}) {|line, h| h[line] = true} 15 end 16 35 36 def filename

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1 module SyntaxErrorSearch 3 class DisplayInvalidBlocks 4 attr_reader :filename 5 6 def initialize(block_array, io: $stderr, filename: nil) 15 end 16 35 36 def filename 37 38 def code_with_filename 45 end 46 63 end 64 end 📕 ❌

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1 module SyntaxErrorSearch 3 class DisplayInvalidBlocks 4 attr_reader :filename 5 6 def initialize(block_array, io: $stderr, filename: nil) 15 end 16 35 36 def filename 37 ❯ 38 def code_with_filename ❯ 45 end 46 63 end 64 end

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1 module SyntaxErrorSearch 3 class DisplayInvalidBlocks 4 attr_reader :filename 5 6 def initialize(block_array, io: $stderr, filename: nil) 15 end 16 35 36 def filename 37 46 63 end 64 end 📕 ❌

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1 module SyntaxErrorSearch 3 class DisplayInvalidBlocks 4 attr_reader :filename 5 ❯ 6 def initialize(block_array, io: $stderr, filename: nil) ❯ 15 end 16 35 36 def filename 37 46 63 end 64 end

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📕 ❌ 1 module SyntaxErrorSearch 3 class DisplayInvalidBlocks 4 attr_reader :filename 5 16 35 36 def filename 37 46 63 end 64 end

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1 module SyntaxErrorSearch 3 class DisplayInvalidBlocks 4 attr_reader :filename ❯ 5 ❯ 16 ❯ 35 ❯ 36 def filename ❯ 37 ❯ 46 63 end 64 end

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1 module SyntaxErrorSearch 3 class DisplayInvalidBlocks 4 attr_reader :filename 63 end 64 end 📕 ✅

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Syntax O K 🥰🥰🥰 1 module SyntaxErrorSearch 3 class DisplayInvalidBlocks 4 attr_reader :filename 63 end 64 end 📕 ✅

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DeadEnd: Missing `end` detected This code has a missing `end`. Ensure that all syntax keywords (`def`, `do`, etc.) have a matching `end`. file: /Users/rschneeman/Documents/projects/dead_end/spec/fixtures/this_project_extra_def.rb.txt simplified: 1 module SyntaxErrorSearch 3 class DisplayInvalidBlocks 4 attr_reader :filename ❯ 36 def filename ❯ 38 def code_with_filename ❯ 45 end 63 end 64 end

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Internals

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module Kernel module_function def require(file) dead_end_original_require(file) rescue SyntaxError => e DeadEnd.handle_error(e) end end dead_end/auto.rb

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# ... Timeout.timeout(timeout) do record_dir ||= ENV["DEBUG"] ? "tmp" : nil search = CodeSearch.new(source, record_dir: record_dir).call end # ... dead_end/internals.rb

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# ... Timeout.timeout(timeout) do record_dir ||= ENV["DEBUG"] ? "tmp" : nil search = CodeSearch.new(source, record_dir: record_dir).call end # ...

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# # ## Syntax error detection # # When the frontier holds the syntax error, we can stop searching # # search = CodeSearch.new(<<~EOM) # def dog # def lol # end # EOM # # search.call # # search.invalid_blocks.map(&:to_s) # => # # => ["def lol\n"] # code_search.rb

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end # Main search loop def call sweep_heredocs sweep_comments until frontier.holds_all_syntax_errors? @tick += 1 if frontier.expand? expand_invalid_block else visit_new_blocks end end @invalid_blocks.concat(frontier.detect_invalid_blocks ) code_search.rb

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end # Main search loop def call sweep_heredocs sweep_comments until frontier.holds_all_syntax_errors? @tick += 1 if frontier.expand? expand_invalid_block else visit_new_blocks end end code_search.rb

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end # Main search loop def call sweep_heredocs sweep_comments until frontier.holds_all_syntax_errors? @tick += 1 if frontier.expand? expand_invalid_block else visit_new_blocks end end code_search.rb 📕 ✅ 📕 ❌

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> 1 module SyntaxErrorSearch 3 class DisplayInvalidBlocks 4 attr_reader :filename ❯ 5 ❯ 16 ❯ 35 ❯ 36 def filename ❯ 37 ❯ 46 63 end 64 end 📕 ❌

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> 1 module SyntaxErrorSearch 3 class DisplayInvalidBlocks 4 attr_reader :filename 63 end 64 end 📕 ✅

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# ... end module DeadEnd # ... def self.invalid?(source) source = source.join if source.is_a?(Array) source = source.to_s Ripper.new(source).tap(&:parse).error? end # ... end dead_end.rb

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> 47 def code_with_lines 48 @code_lines.map do |line| 49 next if line.hidden? 50 number = line.line_number.to_s.rjust(@digit_count) 51 if line.empty? 52 "#{number.to_s}#{line}" 53 else 54 string = String.new 55 string << "\e[1;3m" if @invalid_line_hash[line] # Bold, italics 56 string << "#{number.to_s} " 57 string << line.to_s 58 string << "\e[0m" 59 string 60 end 61 end.join 62 end 63 end 64 end

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end # Main search loop def call sweep_heredocs sweep_comments until frontier.holds_all_syntax_errors? @tick += 1 if frontier.expand? expand_invalid_block else visit_new_blocks end end code_search.rb

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end # Main search loop def call sweep_heredocs sweep_comments until frontier.holds_all_syntax_errors? @tick += 1 if frontier.expand? expand_invalid_block else visit_new_blocks end end @invalid_blocks.concat(frontier.detect_invalid_blocks ) code_search.rb

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def expand? return false if @frontier.empty? # ... # Expand all blocks before moving to unvisited lines frontier_indent >= unvisited_indent end code_frontier.rb

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def expand? return false if @frontier.empty? # ... # Expand all blocks before moving to unvisited lines frontier_indent >= unvisited_indent end code_frontier.rb

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end # Main search loop def call sweep_heredocs sweep_comments until frontier.holds_all_syntax_errors? @tick += 1 if frontier.expand? expand_invalid_block else visit_new_blocks end end @invalid_blocks.concat(frontier.detect_invalid_blocks ) code_search.rb

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end # Main search loop def call sweep_heredocs sweep_comments until frontier.holds_all_syntax_errors? @tick += 1 if frontier.expand? expand_invalid_block else visit_new_blocks end end @invalid_blocks.concat(frontier.detect_invalid_blocks ) code_search.rb

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# Parses the most indented lines into blocks that are marked # and added to the frontier def visit_new_blocks max_indent = frontier.next_indent_line&.indent while (line = frontier.next_indent_line) && (line.indent == max_indent) @parse_blocks_from_indent_line.each_neighbor_block(frontier.next_indent_line) do |block| record(block: block, name: "add") block.mark_invisible if block.valid? push(block, name: "add") end end end code_search.rb

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> 47 def code_with_lines 48 @code_lines.map do |line| 49 next if line.hidden? 50 number = line.line_number.to_s.rjust(@digit_count) 51 if line.empty? 52 "#{number.to_s}#{line}" 53 else 54 string = String.new 55 string << "\e[1;3m" if @invalid_line_hash[line] # Bold, italics 56 string << "#{number.to_s} " 57 string << line.to_s 58 string << "\e[0m" ❯ 59 string 60 end 61 end.join 62 end 63 end 64 end

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> 47 def code_with_lines 48 @code_lines.map do |line| 49 next if line.hidden? 50 number = line.line_number.to_s.rjust(@digit_count) 51 if line.empty? 52 "#{number.to_s}#{line}" 53 else 54 string = String.new 55 string << "\e[1;3m" if @invalid_line_hash[line] # Bold, italics 56 string << "#{number.to_s} " 57 string << line.to_s ❯ 58 string << "\e[0m" ❯ 59 string 60 end 61 end.join 62 end 63 end 64 end

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> 47 def code_with_lines 48 @code_lines.map do |line| 49 next if line.hidden? 50 number = line.line_number.to_s.rjust(@digit_count) 51 if line.empty? 52 "#{number.to_s}#{line}" 53 else 54 string = String.new 55 string << "\e[1;3m" if @invalid_line_hash[line] # Bold, italics 56 string << "#{number.to_s} " ❯ 57 string << line.to_s ❯ 58 string << "\e[0m" ❯ 59 string 60 end 61 end.join 62 end 63 end 64 end

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> 47 def code_with_lines 48 @code_lines.map do |line| 49 next if line.hidden? 50 number = line.line_number.to_s.rjust(@digit_count) 51 if line.empty? 52 "#{number.to_s}#{line}" 53 else 54 string = String.new 55 string << "\e[1;3m" if @invalid_line_hash[line] # Bold, italics ❯ 56 string << "#{number.to_s} " ❯ 57 string << line.to_s ❯ 58 string << "\e[0m" ❯ 59 string 60 end 61 end.join 62 end 63 end 64 end

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> 47 def code_with_lines 48 @code_lines.map do |line| 49 next if line.hidden? 50 number = line.line_number.to_s.rjust(@digit_count) 51 if line.empty? 52 "#{number.to_s}#{line}" 53 else 54 string = String.new ❯ 55 string << "\e[1;3m" if @invalid_line_hash[line] # Bold, italics ❯ 56 string << "#{number.to_s} " ❯ 57 string << line.to_s ❯ 58 string << "\e[0m" ❯ 59 string 60 end 61 end.join 62 end 63 end 64 end

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> 47 def code_with_lines 48 @code_lines.map do |line| 49 next if line.hidden? 50 number = line.line_number.to_s.rjust(@digit_count) 51 if line.empty? 52 "#{number.to_s}#{line}" 53 else ❯ 54 string = String.new ❯ 55 string << "\e[1;3m" if @invalid_line_hash[line] # Bold, italics ❯ 56 string << "#{number.to_s} " ❯ 57 string << line.to_s ❯ 58 string << "\e[0m" ❯ 59 string 60 end 61 end.join 62 end 63 end 64 end

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# Parses the most indented lines into blocks that are marked # and added to the frontier def visit_new_blocks max_indent = frontier.next_indent_line&.indent while (line = frontier.next_indent_line) && (line.indent == max_indent) @parse_blocks_from_indent_line.each_neighbor_block(frontier.next_indent_line) do |block| record(block: block, name: "add") block.mark_invisible if block.valid? push(block, name: "add") end end end code_search.rb

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# Parses the most indented lines into blocks that are marked # and added to the frontier def visit_new_blocks max_indent = frontier.next_indent_line&.indent while (line = frontier.next_indent_line) && (line.indent == max_indent) @parse_blocks_from_indent_line.each_neighbor_block(frontier.next_indent_line) do |block| record(block: block, name: "add") block.mark_invisible if block.valid? push(block, name: "add") end end end code_search.rb

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> 47 def code_with_lines 48 @code_lines.map do |line| 49 next if line.hidden? 50 number = line.line_number.to_s.rjust(@digit_count) 51 if line.empty? 52 "#{number.to_s}#{line}" 53 else ❯ 54 string = String.new ❯ 55 string << "\e[1;3m" if @invalid_line_hash[line] # Bold, italics ❯ 56 string << "#{number.to_s} " ❯ 57 string << line.to_s ❯ 58 string << "\e[0m" ❯ 59 string 60 end 61 end.join 62 end 63 end 64 end

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> 47 def code_with_lines 48 @code_lines.map do |line| 49 next if line.hidden? 50 number = line.line_number.to_s.rjust(@digit_count) 51 if line.empty? 52 "#{number.to_s}#{line}" 53 else 60 end 61 end.join 62 end 63 end 64 end

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# Parses the most indented lines into blocks that are marked # and added to the frontier def visit_new_blocks max_indent = frontier.next_indent_line&.indent while (line = frontier.next_indent_line) && (line.indent == max_indent) @parse_blocks_from_indent_line.each_neighbor_block(frontier.next_indent_line) do |block| record(block: block, name: "add") block.mark_invisible if block.valid? push(block, name: "add") end end end code_search.rb

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sweep(block: block, name: "comments") end # Main search loop def call sweep_heredocs sweep_comments until frontier.holds_all_syntax_errors? @tick += 1 if frontier.expand? expand_invalid_block else visit_new_blocks end end code_search.rb

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sweep(block: block, name: "comments") end # Main search loop def call sweep_heredocs sweep_comments until frontier.holds_all_syntax_errors? @tick += 1 if frontier.expand? expand_invalid_block else visit_new_blocks end end code_search.rb

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sweep(block: block, name: "comments") end # Main search loop def call sweep_heredocs sweep_comments until frontier.holds_all_syntax_errors? @tick += 1 if frontier.expand? expand_invalid_block else visit_new_blocks end end code_search.rb

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> 43 string << "```\n" 44 string 45 end 46 47 def code_with_lines 48 @code_lines.map do |line| 49 next if line.hidden? 50 number = line.line_number.to_s.rjust(@digit_count) 51 if line.empty? ❯ 52 "#{number.to_s}#{line}" 53 else 60 end 61 end.join 62 end 63 end 64 end

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> 43 string << "```\n" 44 string 45 end 46 47 def code_with_lines 48 @code_lines.map do |line| 49 next if line.hidden? 50 number = line.line_number.to_s.rjust(@digit_count) 51 if line.empty? 53 else 60 end 61 end.join 62 end 63 end 64 end

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sweep(block: block, name: "comments") end # Main search loop def call sweep_heredocs sweep_comments until frontier.holds_all_syntax_errors? @tick += 1 if frontier.expand? expand_invalid_block else visit_new_blocks end end code_search.rb

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code_search.rb sweep(block: block, name: "comments") end # Main search loop def call sweep_heredocs sweep_comments until frontier.holds_all_syntax_errors? @tick += 1 if frontier.expand? expand_invalid_block else visit_new_blocks end end

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end end # Given an already existing block in the frontier, expand it to see # if it contains our invalid syntax def expand_invalid_block block = frontier.pop return unless block record(block: block, name: "pop") block = @block_expand.call(block) push(block, name: "expand") end def sweep_heredocs code_search.rb

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end end # Given an already existing block in the frontier, expand it to see # if it contains our invalid syntax def expand_invalid_block block = frontier.pop return unless block record(block: block, name: "pop") block = @block_expand.call(block) push(block, name: "expand") end def sweep_heredocs code_search.rb

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end end # Given an already existing block in the frontier, expand it to see # if it contains our invalid syntax def expand_invalid_block block = frontier.pop return unless block record(block: block, name: "pop") block = @block_expand.call(block) push(block, name: "expand") end def sweep_heredocs code_search.rb

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# frozen_string_literal: true module DeadEnd # This class is responsible for taking a code block that exists # at a far indentaion and then iteratively increasing the block # so that it captures everything within the same indentation block. # # def dog # puts "bow" # puts "wow" # end # # block = BlockExpand.new(code_lines: code_lines) # .call(CodeBlock.new(lines: code_lines[1])) # # puts block.to_s # # => puts "bow" block_expand.rb

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# puts "wow" # end # class BlockExpand def initialize(code_lines: ) @code_lines = code_lines end def call(block) if (next_block = expand_neighbors(block, grab_empty: true)) return next_block end expand_indent(block) end def expand_indent(block) block_expand.rb

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def expand_indent(block) block = AroundBlockScan.new(code_lines: @code_lines, block: block) .skip(:hidden?) .stop_after_kw .scan_adjacent_indent .code_block end def expand_neighbors(block, grab_empty: true) scan = AroundBlockScan.new(code_lines: @code_lines, block: block) .skip(:hidden?) .stop_after_kw .scan_neighbors # Slurp up empties block_expand.rb

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def expand_indent(block) block = AroundBlockScan.new(code_lines: @code_lines, block: block) .skip(:hidden?) .stop_after_kw .scan_adjacent_indent .code_block end def expand_neighbors(block, grab_empty: true) scan = AroundBlockScan.new(code_lines: @code_lines, block: block) .skip(:hidden?) .stop_after_kw .scan_neighbors # Slurp up empties block_expand.rb

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def expand_indent(block) block = AroundBlockScan.new(code_lines: @code_lines, block: block) .skip(:hidden?) .stop_after_kw .scan_adjacent_indent .code_block end def expand_neighbors(block, grab_empty: true) scan = AroundBlockScan.new(code_lines: @code_lines, block: block) .skip(:hidden?) .stop_after_kw .scan_neighbors # Slurp up empties block_expand.rb

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def expand_indent(block) block = AroundBlockScan.new(code_lines: @code_lines, block: block) .skip(:hidden?) .stop_after_kw .scan_adjacent_indent .code_block end def expand_neighbors(block, grab_empty: true) scan = AroundBlockScan.new(code_lines: @code_lines, block: block) .skip(:hidden?) .stop_after_kw .scan_neighbors # Slurp up empties block_expand.rb

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def expand_indent(block) block = AroundBlockScan.new(code_lines: @code_lines, block: block) .skip(:hidden?) .stop_after_kw .scan_adjacent_indent .code_block end def expand_neighbors(block, grab_empty: true) scan = AroundBlockScan.new(code_lines: @code_lines, block: block) .skip(:hidden?) .stop_after_kw .scan_neighbors # Slurp up empties block_expand.rb

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> 41 string << "#".rjust(@digit_count) + " filename: #{filename}\n\n" if filename 42 string << code_with_lines 43 string << "```\n" 44 string 45 end 46 47 def code_with_lines 48 @code_lines.map do |line| 49 next if line.hidden? 50 number = line.line_number.to_s.rjust(@digit_count) 51 if line.empty? ❯ 52 "#{number.to_s}#{line}" 53 else 60 end 61 end.join 62 end 63 end 64 end

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> 42 string << code_with_lines 43 string << "```\n" 44 string 45 end 46 47 def code_with_lines 48 @code_lines.map do |line| 49 next if line.hidden? 50 number = line.line_number.to_s.rjust(@digit_count) ❯ 51 if line.empty? ❯ 53 else ❯ 60 end 61 end.join 62 end 63 end 64 end

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> 42 string << code_with_lines 43 string << "```\n" 44 string 45 end 46 47 def code_with_lines 48 @code_lines.map do |line| 49 next if line.hidden? 50 number = line.line_number.to_s.rjust(@digit_count) 61 end.join 62 end 63 end 64 end

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sweep(block: block, name: "comments") end # Main search loop def call sweep_heredocs sweep_comments until frontier.holds_all_syntax_errors? @tick += 1 if frontier.expand? expand_invalid_block else visit_new_blocks end end code_search.rb

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sweep(block: block, name: "comments") end # Main search loop def call sweep_heredocs sweep_comments until frontier.holds_all_syntax_errors? @tick += 1 if frontier.expand? expand_invalid_block else visit_new_blocks end end code_search.rb

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def expand_indent(block) block = AroundBlockScan.new(code_lines: @code_lines, block: block) .skip(:hidden?) .stop_after_kw .scan_adjacent_indent .code_block end def expand_neighbors(block, grab_empty: true) scan = AroundBlockScan.new(code_lines: @code_lines, block: block) .skip(:hidden?) .stop_after_kw .scan_neighbors # Slurp up empties block_expand.rb

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code_line.rb class CodeLine TRAILING_SLASH = ("\\" + $/).freeze attr_reader :line, :index, :indent, :original_line def initialize(line: , index:) @original_line = line.freeze @line = @original_line if line.strip.empty? @empty = true @indent = 0 else @empty = false @indent = SpaceCount.indent(line) end @index = index @status = nil # valid, invalid, unknown

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private def lex_detect! lex_array = LexAll.new(source: line) kw_count = 0 end_count = 0 lex_array.each_with_index do |lex, index| next unless lex.type == :on_kw case lex.token when 'if', 'unless', 'while', 'until' # Only count if/unless when it's not a "trailing" if/unless kw_count += 1 if !lex.expr_label? when 'def', 'case', 'for', 'begin', 'class', 'module', 'do' kw_count += 1 when 'end' end_count += 1 end code_line.rb

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> source_code = %q{ string = <<~EOM "I am a here doc" if true EOM } Ripper.lex(source_code)

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> source_code = %q{ string = <<~EOM "I am a here doc" if true EOM } Ripper.lex(source_code) [[[1, 0], :on_ignored_nl, "\n", BEG], [[2, 0], :on_ident, "string", CMDARG], [[2, 6], :on_sp, " ", CMDARG], [[2, 7], :on_op, "=", BEG], [[2, 8], :on_sp, " ", BEG], [[2, 9], :on_heredoc_beg, "<<~EOM", BEG], [[2, 15], :on_nl, "\n", BEG], [[3, 0], :on_tstring_content, " \"I am a here doc\" if true\n", BEG], [[4, 0], :on_tstring_content, "EOM \n", BEG]]

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> source_code = %q{ string = <<~EOM "I am a here doc" if true EOM } Ripper.lex(source_code) [[[1, 0], :on_ignored_nl, "\n", BEG], [[2, 0], :on_ident, "string", CMDARG], [[2, 6], :on_sp, " ", CMDARG], [[2, 7], :on_op, "=", BEG], [[2, 8], :on_sp, " ", BEG], [[2, 9], :on_heredoc_beg, "<<~EOM", BEG], [[2, 15], :on_nl, "\n", BEG], [[3, 0], :on_tstring_content, " \"I am a here doc\" if true\n", BEG], [[4, 0], :on_tstring_content, "EOM \n", BEG]]

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> source_code = %q{ string = <<~EOM "I am a here doc" if true EOM } Ripper.lex(source_code) [[[1, 0], :on_ignored_nl, "\n", BEG], [[2, 0], :on_ident, "string", CMDARG], [[2, 6], :on_sp, " ", CMDARG], [[2, 7], :on_op, "=", BEG], [[2, 8], :on_sp, " ", BEG], [[2, 9], :on_heredoc_beg, "<<~EOM", BEG], [[2, 15], :on_nl, "\n", BEG], [[3, 0], :on_tstring_content, " \"I am a here doc\" if true\n", BEG], [[4, 0], :on_tstring_content, "EOM \n", BEG]]

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> source_code = %q{ string = <<~EOM "I am a here doc" if true EOM } Ripper.lex(source_code.lines[2])

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> [[[1, 0], :on_sp, " ", BEG], [[1, 4], :on_tstring_beg, "\"", BEG], [[1, 5], :on_tstring_content, "I am a here doc", BEG], [[1, 20], :on_tstring_end, "\"", END], [[1, 21], :on_sp, " ", END], [[1, 22], :on_kw, "if", BEG|LABEL], [[1, 24], :on_sp, " ", BEG|LABEL], [[1, 25], :on_kw, "true", END], [[1, 29], :on_nl, "\n", BEG]] source_code = %q{ string = <<~EOM "I am a here doc" if true EOM } Ripper.lex(source_code.lines[2])

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private def lex_detect! lex_array = LexAll.new(source: line) kw_count = 0 end_count = 0 lex_array.each_with_index do |lex, index| next unless lex.type == :on_kw case lex.token when 'if', 'unless', 'while', 'until' # Only count if/unless when it's not a "trailing" if/unless kw_count += 1 if !lex.expr_label? when 'def', 'case', 'for', 'begin', 'class', 'module', 'do' kw_count += 1 when 'end' end_count += 1 end code_line.rb

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sweep(block: block, name: "comments") end # Main search loop def call sweep_heredocs sweep_comments until frontier.holds_all_syntax_errors? @tick += 1 if frontier.expand? expand_invalid_block else visit_new_blocks end end code_search.rb

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sweep(block: block, name: "comments") end # Main search loop def call sweep_heredocs sweep_comments until frontier.holds_all_syntax_errors? @tick += 1 if frontier.expand? expand_invalid_block else visit_new_blocks end end code_search.rb

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> 14 @invalid_line_hash = @lines.each_with_object({}) {|line, h| h[line] = true} 15 end 16 17 def call ❯ 18 @io.puts <<~EOM ❯ 19 ❯ 20 DeadEnd: A syntax error was detected ❯ 21 ❯ 22 This code has an unmatched `end` this is caused by either ❯ 23 missing a syntax keyword (`def`, `do`, etc.) or inclusion ❯ 24 of an extra `end` line: ❯ 25 EOM 26 27 @io.puts(<<~EOM) if filename 28 file: #{filename} 29 EOM 30 31 @io.puts <<~EOM

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> 14 @invalid_line_hash = @lines.each_with_object({}) {|line, h| h[line] = true} 15 end 16 17 def call 26 27 @io.puts(<<~EOM) if filename 28 file: #{filename} 29 EOM 30 31 @io.puts <<~EOM 32 #{code_with_filename} 33 EOM 34 end 35 36 def filename 37 38 def code_with_filename 39 string = String.new("")

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> 14 @invalid_line_hash = @lines.each_with_object({}) {|line, h| h[line] = true} 15 end 16 17 def call 26 ❯ 27 @io.puts(<<~EOM) if filename ❯ 28 file: #{filename} ❯ 29 EOM 30 31 @io.puts <<~EOM 32 #{code_with_filename} 33 EOM 34 end 35 36 def filename 37 38 def code_with_filename 39 string = String.new("")

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> 14 @invalid_line_hash = @lines.each_with_object({}) {|line, h| h[line] = true} 15 end 16 17 def call 26 30 ❯ 31 @io.puts <<~EOM ❯ 32 #{code_with_filename} ❯ 33 EOM 34 end 35 36 def filename 37 38 def code_with_filename 39 string = String.new("") 40 string << "```\n" 41 string << "#".rjust(@digit_count) + " filename: #{filename}\n\n" if filename 42 string << code_with_lines

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> 14 @invalid_line_hash = @lines.each_with_object({}) {|line, h| h[line] = true} 15 end 16 17 def call 26 30 34 end 35 36 def filename 37 38 def code_with_filename 39 string = String.new("") 40 string << "```\n" 41 string << "#".rjust(@digit_count) + " filename: #{filename}\n\n" if filename 42 string << code_with_lines 43 string << "```\n" 44 string 45 end

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sweep(block: block, name: "comments") end # Main search loop def call sweep_heredocs sweep_comments until frontier.holds_all_syntax_errors? @tick += 1 if frontier.expand? expand_invalid_block else visit_new_blocks end end code_search.rb

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$ dead_end bad.rb --record tmp/

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sweep(block: block, name: "comments") end # Main search loop def call sweep_heredocs sweep_comments until frontier.holds_all_syntax_errors? @tick += 1 if frontier.expand? expand_invalid_block else visit_new_blocks end end code_search.rb

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def call sweep_heredocs sweep_comments until frontier.holds_all_syntax_errors? @tick += 1 if frontier.expand? expand_invalid_block else visit_new_blocks end end @invalid_blocks.concat(frontier.detect_invalid_blocks ) @invalid_blocks.sort_by! {|block| block.starts_at } self end code_search.rb

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# Example: # # combination([:a, :b, :c, :d]) # # => [[:a], [:b], [:c], [:d], # [:a, :b], [:a, :c], [:a, :d], # [:b, :c], [:b, :d], [:c, :d], # [:a, :b, :c], [:a, :b, :d], [:a, :c, :d], # [:b, :c, :d], # [:a, :b, :c, :d]] def self.combination(array) guesses = [] 1.upto(array.length).each do |size| guesses.concat(array.combination(size).to_a) end guesses end code_frontier.rb

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# Example: # # combination([:a, :b, :c, :d]) # # => [[:a], [:b], [:c], [:d], # [:a, :b], [:a, :c], [:a, :d], # [:b, :c], [:b, :d], [:c, :d], # [:a, :b, :c], [:a, :b, :d], [:a, :c, :d], # [:b, :c, :d], # [:a, :b, :c, :d]] def self.combination(array) guesses = [] 1.upto(array.length).each do |size| guesses.concat(array.combination(size).to_a) end guesses end code_frontier.rb

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# Given that we know our syntax error exists somewhere in our frontier, we want to find # the smallest possible set of blocks that contain all the syntax errors def detect_invalid_blocks self.class.combination(@frontier.select(&:invalid?)).detect do |block_array| holds_all_syntax_errors?(block_array) end || [] end end end code_frontier.rb

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guesses end # Given that we know our syntax error exists somewhere in our frontier, we want to find # the smallest possible set of blocks that contain all the syntax errors def detect_invalid_blocks self.class.combination(@frontier.select(&:invalid?)).detect do |block_array| holds_all_syntax_errors?(block_array) end || [] end end end code_frontier.rb

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Timeout.timeout(timeout) do record_dir ||= ENV["DEBUG"] ? "tmp" : nil search = CodeSearch.new(source, record_dir: record_dir).call end blocks = search.invalid_blocks DisplayInvalidBlocks.new( blocks: blocks, filename: filename, terminal: terminal, code_lines: search.code_lines, invalid_obj: invalid_type(source), io: io ).call dead_end/internals.rb

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Timeout.timeout(timeout) do record_dir ||= ENV["DEBUG"] ? "tmp" : nil search = CodeSearch.new(source, record_dir: record_dir).call end blocks = search.invalid_blocks DisplayInvalidBlocks.new( blocks: blocks, filename: filename, terminal: terminal, code_lines: search.code_lines, invalid_obj: invalid_type(source), io: io ).call dead_end/internals.rb

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Timeout.timeout(timeout) do record_dir ||= ENV["DEBUG"] ? "tmp" : nil search = CodeSearch.new(source, record_dir: record_dir).call end blocks = search.invalid_blocks DisplayInvalidBlocks.new( blocks: blocks, filename: filename, terminal: terminal, code_lines: search.code_lines, invalid_obj: invalid_type(source), io: io ).call dead_end/internals.rb

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> DeadEnd: Missing `end` detected This code has a missing `end`. Ensure that all syntax keywords (`def`, `do`, etc.) have a matching `end`. file: /Users/rschneeman/Documents/projects/dead_end/spec/fixtures/this_project_extr simplified: 1 module SyntaxErrorSearch 3 class DisplayInvalidBlocks 4 attr_reader :filename ❯ 36 def filename ❯ 38 def code_with_filename ❯ 45 end 63 end 64 end

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dead_end

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Are you a dev?

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Are you an open source dev?

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Are you a Ruby core dev?

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❤ 🙏 🙏

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Lexing Parsing Syntax SyntaxErrors AI Pathfinding and goal seeking

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@schneems

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Questions?