Ruby debugging with puts, tap and Hirb
I use puts heaps when debugging. Combined with tap, it’s pretty handy. You can jump right in the middle of a method chain without having to move things around into variables.
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x = long.chain.of.methods.tap {|x| puts x }.to.do.something.with
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I thought hey why don’t I merge the two? And for bonus points, add in Hirb’s table display to format my models nicely. These are fairly personal customizations, and aren’t specific to a project, so I put them in my own ~/.railsrc file rather than each project.
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# config/initializers/developer_specific_customizations.rb if %w(development test).include?(Rails.env) railsrc = "#{ENV['HOME']}/.railsrc" load(railsrc) if File.exist?(railsrc) end # ~/.railsrc require 'hirb' Hirb.enable :pager => false class Object def tapp(prefix = nil, &block) block ||= lambda {|x| x } tap do |x| value = block[x] value = Hirb::View.formatter.format_output(value) || value.inspect if prefix print prefix if value.lines.count > 1 print ":\n" else print ": " end end puts value end end end # Usage (in your spec files, perhaps?) "hello".tapp # => hello "hello".tapp('a') # => a - "hello "hello".tapp(&:length) # => 5 MyModel.first.tapp # => # +----+-------------------------+ # | id | created_at | # +----+-------------------------+ # | 7 | 2009-12-29 00:15:56 UTC | # +----+-------------------------+ # 1 row in set |
