Module: Doing::Pager

Defined in:
lib/doing/pager.rb

Overview

Pagination

Class Method Summary collapse

Class Method Details

.page(text) ⇒ Object 



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# File 'lib/doing/pager.rb', line 15

def page(text)
  unless @paginate
    puts text
    return
  end

  read_io, write_io = IO.pipe

  input = $stdin

  pid = Kernel.fork do
    write_io.close
    input.reopen(read_io)
    read_io.close

    # Wait until we have input before we start the pager
    IO.select [input]

    pager = which_pager
    Doing.logger.debug('Pager:', "Using #{pager}")
    begin
      exec(pager.join(' '))
    rescue SystemCallError => e
      raise Errors::DoingStandardError, "Pager error, #{e}"
    end
  end

  begin
    read_io.close
    write_io.write(text)
    write_io.close
  rescue SystemCallError => e
    raise Errors::DoingStandardError, "Pager error, #{e}"
  end

  _, status = Process.waitpid2(pid)
  status.success?
end

.paginate ⇒ Object 



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# File 'lib/doing/pager.rb', line 7

def paginate
  @paginate ||= false
end

.paginate=(should_paginate) ⇒ Object 



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# File 'lib/doing/pager.rb', line 11

def paginate=(should_paginate)
  @paginate = should_paginate
end

.which_pager ⇒ Object 



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# File 'lib/doing/pager.rb', line 54

def which_pager
  pagers = [ENV['GIT_PAGER'], ENV['PAGER']]

  if Util.exec_available('git')
    git_pager = `git config --get-all core.pager || true`.split.first
    git_pager && pagers.push(git_pager)
  end

  pagers.concat(%w[bat less more pager])

  pagers.select! do |f|
    if f
      if f.strip =~ /[ |]/
        f
      elsif f == 'most'
        Doing.logger.warn('most not allowed as pager')
        false
      else
        system "which #{f}", out: File::NULL, err: File::NULL
      end
    else
      false
    end
  end

  pg = pagers.first
  args = case pg
         when /^more$/
           ' -r'
         when /^less$/
           ' -Xr'
         when /^bat$/
           ' -p --pager="less -Xr"'
         else
           ''
         end

  [pg, args]
end