[Kaigi] Beware the Dead End

Nothing stops a program from executing quite as fast as a syntax error. After years of “unexpected end” in my dev life, I decided to “do” something about it. In this talk we'll cover lexing, parsing, and indentation informed syntax tree search that power that dead_end Ruby library.

PS I also gave this talk at RubyConf, but with a whole bunch of new content. I recommend that one instead.

Transcript

1. Beware the Dreaded Dead End!!! By @schneems
4. Beware the Dreaded Dead End!!! By @schneems
5. > # <= 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
6. > 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’
7. > 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’
8. 🤔
9. > 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.)
10. >
11. > # 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’
12. > 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
13. 0 25 50 75 100 April May June July (I did not do a study)
14. (This is a lie) -30 -15 0 15 30 45 60 April May June July August
15. (Also a lie) 7% 8% 11% 11% 31% 32%
16. 🥰
17. $ gem install dead_end
18. > 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
19. > 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
20. > 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
21. > 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
22. > 1 class Cat 2 def meow ❯ 3 Animal.call do |a ❯ 5 end 6 end 7 end DeadEnd: Unmatched `|` character detected
23. > 1 class Cat 2 def meow ❯ 3 Animal.call do |a ❯ 5 end 6 end 7 end DeadEnd: Unmatched `|` character detected ? ? ?
24. $ gem install dead_end
25. Syntax errors
26. Lexing & Parsing
27. AI
28. dead_end
29. Internals
30. 🤚
31. @schneems
32. @schneems
34. 📕 How to Open Source
35. Heroku
36. Heroku
37. NoMemoryError ScriptError LoadError SyntaxError SecurityError SignalException KeyError StandardError ArgumentError EncodingError IOError EOFError I am Exceptional
38. > Dir.chhhdir("/tmp") do puts `ls` end
39. > Dir.chhhdir("/tmp") do puts `ls` end # unde fi ned method `chhhdir' for # Dir:Class (NoMethodError ) # Did you mean? chdir
40. >
41. 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
42. 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 }
43. if / end unless / end while / end until / end def / end for / end begin / end class / end module / end do / end
44. > Dir.chdir("lol") puts `ls` end ☠☠☠
45. > Dir.chdir("lol") puts `ls` end ??
46. > Dir.chdir("/tmp") Dir.chdir("lol") do puts `ls` end
47. > def bark puts "woof" end bark() # => "woof"
48. > def bark puts "woof" end bark do puts "not a syntax error" end # => "woof"
49. > expect(WebMock).to have_requested( :post, "localhost:#{port}" ). end $ ruby -wc scratch.rb Syntax OK
50. 📓
51. Lexing & Parsing
52. "hello world" Ripper.lex >
54. "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] ] >
55. [ [[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] ]
56. [ [[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] ]
57. [ [[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] ]
58. while b != 0 if a > b a = a - b else b = b - a end end return a Ripper.parse
59. while b != 0 # if a > b a = a - b else b = b - a end end return a Ripper.parse :(
60. 🤔
61. while b != 0 # if a > b a = a - b else b = b - a end end return a Ripper.parse :(
62. while b != 0 # if a > b # a = a - b # else # b = b - a # end end return a Ripper.parse :)
63. while b != 0 # if a > b # a = a - b # else # b = b - a # end end return a Ripper.parse :)
64. AI
65. Artificial Intelligence Algorithm
66. Artificial Intelligence Algorithm
67. Pathfinding Credit: Factorio 'New pathfinding algorithm'
68. Credit @redblobgames: Introduction to the A-star Algorithm
69. Pathfinding Credit: Factorio 'New pathfinding algorithm'
70. Tree
 Search
 "Reti Draw" Endgame Chess problem by Richard Reti (1921)
71. Tree
 Search
 BOTVINNIK, M.M. (1984). "Computers in Chess Solving Inexact Search Problems"
72. Non-optimal Play
87. Checkmate Black
88. Optimal Draw Play
97. Draw
98. Tree
 Search
 BOTVINNIK, M.M. (1984). "Computers in Chess Solving Inexact Search Problems"
99. AI ~ Search
101. while b != 0 if a > b a = a - b else b = b - a end end return a Ripper.parse
102. while b != 0 # if a > b a = a - b else b = b - a end end return a Ripper.parse
103. ❌🌳💔
104. > Dir.chdir("/tmp") Dir.chdir("lol") end do??? do??? puts `ls`
105. > Dir.chdir("/tmp") Dir.chdir("lol") end do puts `ls`🥰
106. while b != 0 # if a > b # a = a - b # else # b = b - a # end end return a Ripper.parse
107. 🌳 ❌ 💔
108. demo
109. 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' 📕 ❌
110. 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
111. 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
112. 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
113. 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
114. 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
115. 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
116. 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
117. 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 📕 ❌
118. 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
119. 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 📕 ❌
120. 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
121. 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 📕 ❌
122. 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
123. 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 📕 ❌
124. 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
125. 42 string << code_with_lines 43 string << "```\n" 44 string 45 end 46 47 def code_with_lines 62 end 63 end 64 end 📕 ❌
126. 42 string << code_with_lines 43 string << "```\n" 44 string 45 end 46 ❯ 47 def code_with_lines ❯ 62 end 63 end 64 end
127. 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 📕 ❌
128. 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
129. 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
130. 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
131. 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
132. 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
133. 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
134. 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
135. 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 📕 ❌
136. 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
137. 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
138. 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
139. 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
140. 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
141. 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
142. 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
143. 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
144. 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 📕 ❌
145. 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
146. 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 📕 ❌
147. 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
148. 📕 ❌ 1 module SyntaxErrorSearch 3 class DisplayInvalidBlocks 4 attr_reader :filename 5 16 35 36 def filename 37 46 63 end 64 end
149. 1 module SyntaxErrorSearch 3 class DisplayInvalidBlocks 4 attr_reader :filename ❯ 5 ❯ 16 ❯ 35 ❯ 36 def filename ❯ 37 ❯ 46 63 end 64 end
150. 1 module SyntaxErrorSearch 3 class DisplayInvalidBlocks 4 attr_reader :filename 63 end 64 end 📕 ✅
151. Syntax O K 🥰🥰🥰 1 module SyntaxErrorSearch 3 class DisplayInvalidBlocks 4 attr_reader :filename 63 end 64 end 📕 ✅
152. 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
153. Internals
154. 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
155. # ... Timeout.timeout(timeout) do record_dir ||= ENV["DEBUG"] ? "tmp" : nil search = CodeSearch.new(source, record_dir: record_dir).call end # ... dead_end/internals.rb
156. # ... Timeout.timeout(timeout) do record_dir ||= ENV["DEBUG"] ? "tmp" : nil search = CodeSearch.new(source, record_dir: record_dir).call end # ...
157. # # ## 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
158. 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
159. 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
160. 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 📕 ✅ 📕 ❌
161. > 1 module SyntaxErrorSearch 3 class DisplayInvalidBlocks 4 attr_reader :filename ❯ 5 ❯ 16 ❯ 35 ❯ 36 def filename ❯ 37 ❯ 46 63 end 64 end 📕 ❌
162. > 1 module SyntaxErrorSearch 3 class DisplayInvalidBlocks 4 attr_reader :filename 63 end 64 end 📕 ✅
163. # ... 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
164. > 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
165. 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
166. 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
167. def expand? return false if @frontier.empty? # ... # Expand all blocks before moving to unvisited lines frontier_indent >= unvisited_indent end code_frontier.rb
168. def expand? return false if @frontier.empty? # ... # Expand all blocks before moving to unvisited lines frontier_indent >= unvisited_indent end code_frontier.rb
169. 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
170. 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
171. # 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
172. > 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
173. > 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
174. > 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
175. > 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
176. > 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
177. > 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
178. # 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
179. # 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
180. > 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
181. > 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
182. # 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
183. 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
184. 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
185. 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
186. > 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
187. > 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
188. 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
189. 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
190. 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
191. 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
192. 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
193. # 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
194. # 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
195. 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
196. 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
197. 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
198. 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
199. 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
200. > 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
201. > 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
202. > 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
203. 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
204. 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
205. 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
206. 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
207. 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
208. > source_code = %q{ string = <<~EOM "I am a here doc" if true EOM } Ripper.lex(source_code)
209. > 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]]
210. > 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]]
211. > 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]]
212. > source_code = %q{ string = <<~EOM "I am a here doc" if true EOM } Ripper.lex(source_code.lines[2])
213. > [[[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])
214. 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
215. 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
216. 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
217. > 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
218. > 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("")
219. > 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("")
220. > 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
221. > 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
222. 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
223. $ dead_end bad.rb --record tmp/
226. 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
227. 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
228. # 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
229. # 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
230. # 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
231. 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
232. 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
233. 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
234. 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
235. > 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
236. dead_end
237. Are you a dev?
240. Are you an open source dev?
242. Are you a Ruby core dev?
243. ❤ 🙏 🙏
244. Lexing Parsing Syntax SyntaxErrors AI Pathfinding and goal seeking
249. @schneems
251. Questions?