Add bin and edit workflow

bin/gems/pry-0.15.2/lib/pry/commands/wtf.rb

@@ -0,0 +1,95 @@
+# frozen_string_literal: true
+
+class Pry
+  class Command
+    class Wtf < Pry::ClassCommand
+      match(/wtf([?!]*)/)
+      group 'Context'
+      description 'Show the backtrace of the most recent exception.'
+      options listing: 'wtf?'
+
+      banner <<-'BANNER'
+        Usage: wtf[?|!]
+
+        Shows a few lines of the backtrace of the most recent exception (also available
+        as `_ex_.backtrace`). If you want to see more lines, add more question marks or
+        exclamation marks.
+
+        wtf?
+        wtf?!???!?!?
+
+        # To see the entire backtrace, pass the `-v` or `--verbose` flag.
+        wtf -v
+      BANNER
+
+      RUBY_FRAME_PATTERN = /\A(?<file>(.+)):(?<line>(\d+))/.freeze
+
+      def options(opt)
+        opt.on :v, :verbose, "Show the full backtrace"
+        opt.on :c, :code, "Show code corresponding to the backtrace frame"
+      end
+
+      def process
+        unless pry_instance.last_exception
+          raise Pry::CommandError, "No most-recent exception"
+        end
+
+        text = ''.dup
+        unwind_exceptions.each_with_index do |exception, i|
+          title = (i == 0 ? 'Exception' : 'Caused by')
+          text << format_header(title, exception)
+          text << format_backtrace(exception.backtrace)
+        end
+        output.puts(text)
+      end
+
+      private
+
+      def unwind_exceptions
+        exception_list = []
+        exception = pry_instance.last_exception
+
+        while exception
+          exception_list << exception
+          exception = (exception.cause if exception.respond_to?(:cause))
+        end
+
+        exception_list
+      end
+
+      def format_header(title, exception)
+        "#{bold(title + ':')} #{exception.class}: #{exception}\n--\n"
+      end
+
+      def format_backtrace(backtrace)
+        lines = trim_backtrace(backtrace).map do |frame|
+          next frame unless opts.code?
+
+          match = frame.match(RUBY_FRAME_PATTERN)
+          code = read_line(match[:file], match[:line].to_i)
+          [bold(frame), code].join("\n")
+        end
+
+        Pry::Code.new(lines.compact, 0, :text).with_line_numbers.to_s
+      end
+
+      def trim_backtrace(backtrace)
+        return backtrace if opts.verbose?
+
+        size_of_backtrace = [captures[0].size, 0.5].max * 10
+        backtrace.first(size_of_backtrace)
+      end
+
+      def read_line(file, line)
+        File.open(file, 'r') do |f|
+          (line - 1).times { f.gets }
+          f.gets
+        end
+      rescue Errno::ENOENT
+        nil
+      end
+    end
+
+    Pry::Commands.add_command(Pry::Command::Wtf)
+  end
+end