% bundle exec pry
[1] pry(main)> require './a.rb'
=> true
[2] pry(main)> foo
RuntimeError: two
from /path/to/a.rb:4:in `rescue in foo'
[3] pry(main)> cd-cause

From: /path/to/.rbenv/versions/2.0.0-p353/lib/ruby/gems/2.0.0/gems/pry-rescue-1.4.1/lib/pry-rescue.rb @ line 207 PryRescue.with_program_name:

    202: def with_program_name name
    203:   before = $PROGRAM_NAME
    204:   $PROGRAM_NAME = name
    205:   yield
    206: ensure
 => 207:   $PROGRAM_NAME = before
    208: end

[1] pry(PryRescue)>

GEM
  remote: https://rubygems.org/
  specs:
    byebug (3.4.0)
      columnize (~> 0.8)
      debugger-linecache (~> 1.2)
      slop (~> 3.6)
    coderay (1.1.0)
    columnize (0.8.9)
    debugger-linecache (1.2.0)
    interception (0.5)
    method_source (0.8.2)
    pry (0.10.1)
      coderay (~> 1.1.0)
      method_source (~> 0.8.1)
      slop (~> 3.4)
    pry-byebug (2.0.0)
      byebug (~> 3.4)
      pry (~> 0.10)
    pry-rescue (1.4.1)
      interception (>= 0.5)
      pry
    slop (3.6.0)

PLATFORMS
  ruby

DEPENDENCIES
  pry
  pry-byebug
  pry-rescue