Module: Kernel

Defined in:
lib/passive_support/core_ext/kernel/debugger.rb,
lib/passive_support/core_ext/kernel/requires.rb,
lib/passive_support/core_ext/kernel/reporting.rb,
lib/passive_support/core_ext/kernel/daemonizing.rb

Instance Method Summary collapse

Instance Method Details

#breakpoint ⇒ Object 



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# File 'lib/passive_support/core_ext/kernel/debugger.rb', line 11

def breakpoint
  message = "\n***** The 'breakpoint' command has been renamed 'debugger' -- please change *****\n"
  defined?(Rails) ? Rails.logger.info(message) : $stderr.puts(message)
  debugger
end

#daemonize ⇒ Object

Turns the current script into a daemon process that detaches from the console. It can be shut down with a TERM signal.



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# File 'lib/passive_support/core_ext/kernel/daemonizing.rb', line 4

def daemonize
  Process.daemon
end

#debugger ⇒ Object

Starts a debugging session if ruby-debug has been loaded (call script/server –debugger to do load it).



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# File 'lib/passive_support/core_ext/kernel/debugger.rb', line 4

def debugger
  message = "\n***** Debugger requested, but was not available: Start server with --debugger to enable *****\n"
  defined?(Rails) ? Rails.logger.info(message) : $stderr.puts(message)
end

#enable_warnings ⇒ Object

Sets $VERBOSE to true for the duration of the block and back to its original value afterwards.



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# File 'lib/passive_support/core_ext/kernel/reporting.rb', line 17

def enable_warnings
  old_verbose, $VERBOSE = $VERBOSE, true
  yield
ensure
  $VERBOSE = old_verbose
end

#require_library_or_gem(library_name) ⇒ Object

Require a library with fallback to RubyGems. Warnings during library loading are silenced to increase signal/noise for application warnings.



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# File 'lib/passive_support/core_ext/kernel/requires.rb', line 4

def require_library_or_gem(library_name)
  silence_warnings do
    begin
      require library_name
    rescue LoadError => cannot_require
      # 1. Requiring the module is unsuccessful, maybe it's a gem and nobody required rubygems yet. Try.
      begin
        require 'rubygems'
      rescue LoadError => rubygems_not_installed
        raise cannot_require
      end
      # 2. Rubygems is installed and loaded. Try to load the library again
      begin
        require library_name
      rescue LoadError => gem_not_installed
        raise cannot_require
      end
    end
  end
end

#silence_stderr ⇒ Object

For compatibility



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# File 'lib/passive_support/core_ext/kernel/reporting.rb', line 25

def silence_stderr #:nodoc:
  silence_stream(STDERR) { yield }
end

#silence_stream(stream) ⇒ Object

Silences any stream for the duration of the block.

silence_stream(STDOUT) do
  puts 'This will never be seen'
end

puts 'But this will'



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# File 'lib/passive_support/core_ext/kernel/reporting.rb', line 36

def silence_stream(stream)
  old_stream = stream.dup
  stream.reopen(RUBY_PLATFORM =~ /(:?mswin|mingw)/ ? 'NUL:' : '/dev/null')
  stream.sync = true
  yield
ensure
  stream.reopen(old_stream)
end

#silence_warnings ⇒ Object

Sets $VERBOSE to nil for the duration of the block and back to its original value afterwards.

silence_warnings do
  value = noisy_call # no warning voiced
end

noisy_call # warning voiced



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# File 'lib/passive_support/core_ext/kernel/reporting.rb', line 9

def silence_warnings
  old_verbose, $VERBOSE = $VERBOSE, nil
  yield
ensure
  $VERBOSE = old_verbose
end

#suppress(*exception_classes) ⇒ Object

Blocks and ignores any exception passed as argument if raised within the block.

suppress(ZeroDivisionError) do
  1/0
  puts "This code is NOT reached"
end

puts "This code gets executed and nothing related to ZeroDivisionError was seen"



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# File 'lib/passive_support/core_ext/kernel/reporting.rb', line 53

def suppress(*exception_classes)
  begin yield
  rescue Exception => e
    raise unless exception_classes.any? { |cls| e.kind_of?(cls) }
  end
end