Piping nanoc show-data through less makes it crash

[gpakosz]

Here is a stacktrace, after I quit less:

$ nanoc show-data |less

Captain! We’ve been hit!

Message:

Errno::EPIPE: Broken pipe - 

Compilation stack:

  (empty)

Stack trace:

  0. /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/cleaning_stream.rb:74:in `write'
  1. /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/cleaning_stream.rb:74:in `puts'
  2. /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/cleaning_stream.rb:74:in `puts'
  3. /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/commands/show-data.rb:103:in `puts'
  4. /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/commands/show-data.rb:103:in `block in print_item_rep_outdatedness'
  5. /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/commands/show-data.rb:49:in `block (2 levels) in sorted_reps_with_prev'
  6. /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/commands/show-data.rb:48:in `each'
  7. /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/commands/show-data.rb:48:in `block in sorted_reps_with_prev'
  8. /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/commands/show-data.rb:47:in `each'
  9. /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/commands/show-data.rb:47:in `sorted_reps_with_prev'
  ... 18 more lines omitted. See full crash log for details.

If you believe this is a bug in nanoc, please do report it at
-> https://github.com/nanoc/nanoc/issues/new <-

A detailed crash log has been written to ./crash.log.

Captain! We’ve been hit!

Message:

Errno::EPIPE: Broken pipe

Compilation stack:

  (empty)

Stack trace:

  0. /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/cleaning_stream.rb:59:in `flush'
  1. /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/cleaning_stream.rb:59:in `flush'
  2. /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/error_handler.rb:322:in ``'
  3. /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/error_handler.rb:322:in `write_system_information'
  4. /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/error_handler.rb:149:in `write_verbose_error'
  5. /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/error_handler.rb:103:in `block in print_error'
  6. /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/error_handler.rb:100:in `open'
  7. /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/error_handler.rb:100:in `print_error'
  8. /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/error_handler.rb:77:in `rescue in handle_while'
  9. /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/error_handler.rb:55:in `handle_while'
  ... 14 more lines omitted. See full crash log for details.

If you believe this is a bug in nanoc, please do report it at
-> https://github.com/nanoc/nanoc/issues/new <-

A detailed crash log has been written to ./crash.log.
/usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/cleaning_stream.rb:59:in `flush': Broken pipe (Errno::EPIPE)
        from /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/cleaning_stream.rb:59:in `flush'
        from /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/error_handler.rb:322:in ``'
        from /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/error_handler.rb:322:in `write_system_information'
        from /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/error_handler.rb:149:in `write_verbose_error'
        from /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/error_handler.rb:103:in `block in print_error'
        from /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/error_handler.rb:100:in `open'
        from /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/error_handler.rb:100:in `print_error'
        from /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/error_handler.rb:77:in `rescue in handle_while'
        from /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/error_handler.rb:55:in `handle_while'
        from /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli/error_handler.rb:26:in `handle_while'
        from /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/lib/nanoc/cli.rb:50:in `run'
        from /usr/local/Cellar/ruby/2.0.0-p0/lib/ruby/gems/2.0.0/gems/nanoc-3.6.3/bin/nanoc:19:in `'
        from /usr/local/Cellar/ruby/2.0.0-p0/bin/nanoc:23:in `load'
        from /usr/local/Cellar/ruby/2.0.0-p0/bin/nanoc:23:in `'
$

[denisdefreyne]

I’ve been unable to reproduce this so far.

This might be more of a problem with less. Does the same problem occur when using more or cat?

[gpakosz]

same with more

I'm reproducing it by doing nanoc show-data | less or nanoc show-data | more and I press q before the end of output.

[denisdefreyne]

Yeah, this actually makes sense. I’m thinking of simply ignoring SIGPIPEs (Signal.trap("PIPE", "IGNORE")) or rescuing them in the appropriate places. Will fix!

[denisdefreyne]

Fixed by #369.