ruby - 使用 pry-byebug 设置条件断点

Question

给定以下代码:

require 'pry-byebug'

10.times.with_index do |i|
  binding.pry
  puts i
end

我想在 pry-byebug 中“循环直到 i == 5 然后中断”。通过运行它 help break，您似乎可以通过“breakpoint #”或“line #”来识别断点。看起来你也可以使用条件，但我没有让它工作:

尝试在第 # 行设置断点:

$  ruby foo.rb

From: /Users/max/Dropbox/work/tmp/pry_debug/foo.rb @ line 5 :

    1: require 'pry-byebug'
    2:
    3: 10.times.with_index do |i|
    4:   binding.pry
 => 5:   puts i
    6: end

[1] pry(main)> break foo.rb:5 if i == 5

  Breakpoint 1: /Users/max/Dropbox/work/tmp/pry_debug/foo.rb @ 5 (Enabled) Condition: i == 5


    2:
    3: 10.times.with_index do |i|
    4:   binding.pry
 => 5:   puts i
    6: end


[2] pry(main)> continue
0

From: /Users/max/Dropbox/work/tmp/pry_debug/foo.rb @ line 5 :

    1: require 'pry-byebug'
    2:
    3: 10.times.with_index do |i|
    4:   binding.pry
 => 5:   puts i
    6: end

[2] pry(main)> i
=> 1

首先设置断点，然后在断点上放置条件:

➜  ~/D/w/t/pry_debug  ruby foo.rb

From: /Users/max/Dropbox/work/tmp/pry_debug/foo.rb @ line 5 :

    1: require 'pry-byebug'
    2:
    3: 10.times.with_index do |i|
    4:   binding.pry
 => 5:   puts i
    6: end

[1] pry(main)> break foo.rb:15

  Breakpoint 1: /Users/max/Dropbox/work/tmp/pry_debug/foo.rb @ 15 (Enabled)



[2] pry(main)> break --condition 1 i == 5
[3] pry(main)> c
0

From: /Users/max/Dropbox/work/tmp/pry_debug/foo.rb @ line 5 :

    1: require 'pry-byebug'
    2:
    3: 10.times.with_index do |i|
    4:   binding.pry
 => 5:   puts i
    6: end

[3] pry(main)> i
=> 1

如您所见，在这两种情况下，pry-byebug 都不遵守条件，因为它停止得太早了。如何让它发挥作用？

Answer 1

我认为一种简单的方法是在您的代码中执行此操作:

require 'pry-byebug'

10.times.with_index do |i|
  binding.pry if i == 5
  puts i
end

或者如果你想在异常时停止，你可以这样做:

require 'pry-byebug'

10.times.with_index do |i|
  puts i rescue binding.pry # if the puts command throws an exception, you'll be taken to pry
end