Class: StackProf::Report

Inherits:
Object
  • Object
show all
Defined in:
lib/stackprof/report.rb

Defined Under Namespace

Classes: StackCursor

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(data) ⇒ Report

Returns a new instance of Report.


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# File 'lib/stackprof/report.rb', line 8

def initialize(data)
  @data = data
end

Instance Attribute Details

#dataObject (readonly)

Returns the value of attribute data


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# File 'lib/stackprof/report.rb', line 11

def data
  @data
end

Instance Method Details

#+(other) ⇒ Object

Raises:

  • (ArgumentError)

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# File 'lib/stackprof/report.rb', line 615

def +(other)
  raise ArgumentError, "cannot combine #{other.class}" unless self.class == other.class
  raise ArgumentError, "cannot combine #{modeline} with #{other.modeline}" unless modeline == other.modeline
  raise ArgumentError, "cannot combine v#{version} with v#{other.version}" unless version == other.version

  f1, f2 = normalized_frames, other.normalized_frames
  frames = (f1.keys + f2.keys).uniq.inject(Hash.new) do |hash, id|
    if f1[id].nil?
      hash[id] = f2[id]
    elsif f2[id]
      hash[id] = f1[id]
      hash[id][:total_samples] += f2[id][:total_samples]
      hash[id][:samples] += f2[id][:samples]
      if f2[id][:edges]
        edges = hash[id][:edges] ||= {}
        f2[id][:edges].each do |edge, weight|
          edges[edge] ||= 0
          edges[edge] += weight
        end
      end
      if f2[id][:lines]
        lines = hash[id][:lines] ||= {}
        f2[id][:lines].each do |line, weight|
          lines[line] = add_lines(lines[line], weight)
        end
      end
    else
      hash[id] = f1[id]
    end
    hash
  end

  d1, d2 = data, other.data
  data = {
    version: version,
    mode: d1[:mode],
    interval: d1[:interval],
    samples: d1[:samples] + d2[:samples],
    gc_samples: d1[:gc_samples] + d2[:gc_samples],
    missed_samples: d1[:missed_samples] + d2[:missed_samples],
    frames: frames
  }

  self.class.new(data)
end

#add_lines(a, b) ⇒ Object


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# File 'lib/stackprof/report.rb', line 58

def add_lines(a, b)
  return b if a.nil?
  return a+b if a.is_a? Integer
  return [ a[0], a[1]+b ] if b.is_a? Integer
  [ a[0]+b[0], a[1]+b[1] ]
end

#convert_to_d3_flame_graph_format(name, stacks, depth) ⇒ Object


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# File 'lib/stackprof/report.rb', line 201

def convert_to_d3_flame_graph_format(name, stacks, depth)
  weight = 0
  children = []
  stacks.chunk do |stack|
    if depth == stack.length - 1
      :leaf
    else
      stack[depth]
    end
  end.each do |val, child_stacks|
    if val == :leaf
      child_stacks.each do |stack|
        weight += stack.last
      end
    else
      frame = @data[:frames][val]
      child_name = "#{ frame[:name] } : #{ frame[:file] }"
      child_data = convert_to_d3_flame_graph_format(child_name, child_stacks, depth + 1)
      weight += child_data["value"]
      children << child_data
    end
  end

  {
    "name" => name,
    "value" => weight,
    "children" => children,
  }
end

#filesObject


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# File 'lib/stackprof/report.rb', line 46

def files
  @data[:files] ||= @data[:frames].inject(Hash.new) do |hash, (addr, frame)|
    if file = frame[:file] and lines = frame[:lines]
      hash[file] ||= Hash.new
      lines.each do |line, weight|
        hash[file][line] = add_lines(hash[file][line], weight)
      end
    end
    hash
  end
end

#flamegraph_row(f, x, y, weight, addr) ⇒ Object


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# File 'lib/stackprof/report.rb', line 194

def flamegraph_row(f, x, y, weight, addr)
  frame = @data[:frames][addr]
  f.print ',' if @rows_started
  @rows_started = true
  f.puts %{{"x":#{x},"y":#{y},"width":#{weight},"frame_id":#{addr},"frame":#{frame[:name].dump},"file":#{frame[:file].dump}}}
end

#frames(sort_by_total = false) ⇒ Object


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# File 'lib/stackprof/report.rb', line 13

def frames(sort_by_total=false)
  @data[:"sorted_frames_#{sort_by_total}"] ||=
    @data[:frames].sort_by{ |iseq, stats| -stats[sort_by_total ? :total_samples : :samples] }.inject({}){|h, (k, v)| h[k] = v; h}
end

#max_samplesObject


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# File 'lib/stackprof/report.rb', line 42

def max_samples
  @data[:max_samples] ||= @data[:frames].values.max_by{ |frame| frame[:samples] }[:samples]
end

#modelineObject


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# File 'lib/stackprof/report.rb', line 34

def modeline
  "#{@data[:mode]}(#{@data[:interval]})"
end

#normalized_framesObject


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# File 'lib/stackprof/report.rb', line 18

def normalized_frames
  id2hash = {}
  @data[:frames].each do |frame, info|
    id2hash[frame.to_s] = info[:hash] = Digest::MD5.hexdigest("#{info[:name]}#{info[:file]}#{info[:line]}")
  end
  @data[:frames].inject(Hash.new) do |hash, (frame, info)|
    info = hash[id2hash[frame.to_s]] = info.dup
    info[:edges] = info[:edges].inject(Hash.new){ |edges, (edge, weight)| edges[id2hash[edge.to_s]] = weight; edges } if info[:edges]
    hash
  end
end

#overall_samplesObject


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# File 'lib/stackprof/report.rb', line 38

def overall_samples
  @data[:samples]
end

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# File 'lib/stackprof/report.rb', line 94

def print_alphabetical_flamegraph(f=STDOUT, skip_common=true)
  print_flamegraph(f, skip_common, true)
end

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# File 'lib/stackprof/report.rb', line 492

def print_callgrind(f = STDOUT)
  f.puts "version: 1"
  f.puts "creator: stackprof"
  f.puts "pid: 0"
  f.puts "cmd: ruby"
  f.puts "part: 1"
  f.puts "desc: mode: #{modeline}"
  f.puts "desc: missed: #{@data[:missed_samples]})"
  f.puts "positions: line"
  f.puts "events: Instructions"
  f.puts "summary: #{@data[:samples]}"

  list = frames
  list.each do |addr, frame|
    f.puts "fl=#{frame[:file]}"
    f.puts "fn=#{frame[:name]}"
    frame[:lines].each do |line, weight|
      f.puts "#{line} #{weight.is_a?(Array) ? weight[1] : weight}"
    end if frame[:lines]
    frame[:edges].each do |edge, weight|
      oframe = list[edge]
      f.puts "cfl=#{oframe[:file]}" unless oframe[:file] == frame[:file]
      f.puts "cfn=#{oframe[:name]}"
      f.puts "calls=#{weight} #{frame[:line] || 0}\n#{oframe[:line] || 0} #{weight}"
    end if frame[:edges]
    f.puts
  end

  f.puts "totals: #{@data[:samples]}"
end

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# File 'lib/stackprof/report.rb', line 231

def print_d3_flamegraph(f=STDOUT, skip_common=true)
  raise "profile does not include raw samples (add `raw: true` to collecting StackProf.run)" unless raw = data[:raw]

  stacks = []
  max_x = 0
  max_y = 0
  while len = raw.shift
    max_y = len if len > max_y
    stack = raw.slice!(0, len+1)
    stacks << stack
    max_x += stack.last
  end

  # d3-flame-grpah supports only alphabetical flamegraph
  stacks.sort!

  require "json"
  json = JSON.generate(convert_to_d3_flame_graph_format("<root>", stacks, 0), max_nesting: false)

  # This html code is almost copied from d3-flame-graph sample code.
  # (Apache License 2.0)
  # https://github.com/spiermar/d3-flame-graph/blob/gh-pages/index.html

  f.print <<-END
<!DOCTYPE html>
<html lang="en">
  <head>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1">

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css">
<link rel="stylesheet" type="text/css" href="https://cdn.jsdelivr.net/gh/spiermar/[email protected]/dist/d3-flamegraph.css">

<style>

/* Space out content a bit */
body {
  padding-top: 20px;
  padding-bottom: 20px;
}

/* Custom page header */
.header {
  padding-bottom: 20px;
  padding-right: 15px;
  padding-left: 15px;
  border-bottom: 1px solid #e5e5e5;
}

/* Make the masthead heading the same height as the navigation */
.header h3 {
  margin-top: 0;
  margin-bottom: 0;
  line-height: 40px;
}

/* Customize container */
.container {
  max-width: 990px;
}

address {
  text-align: right;
}
</style>

<title>stackprof (mode: #{ data[:mode] })</title>

<!-- HTML5 shim and Respond.js for IE8 support of HTML5 elements and media queries -->
<!--[if lt IE 9]>
  <script src="https://oss.maxcdn.com/html5shiv/3.7.2/html5shiv.min.js"></script>
  <script src="https://oss.maxcdn.com/respond/1.4.2/respond.min.js"></script>
<![endif]-->
  </head>
  <body>
<div class="container">
  <div class="header clearfix">
    <nav>
      <div class="pull-right">
        <form class="form-inline" id="form">
          <a class="btn" href="javascript: resetZoom();">Reset zoom</a>
          <a class="btn" href="javascript: clear();">Clear</a>
          <div class="form-group">
            <input type="text" class="form-control" id="term">
          </div>
          <a class="btn btn-primary" href="javascript: search();">Search</a>
        </form>
      </div>
    </nav>
    <h3 class="text-muted">stackprof (mode: #{ data[:mode] })</h3>
  </div>
  <div id="chart">
  </div>
  <address>
    powered by <a href="https://github.com/spiermar/d3-flame-graph">d3-flame-graph</a>
  </address>
  <hr>
  <div id="details">
  </div>
</div>

<!-- D3.js -->
<script src="https://d3js.org/d3.v4.min.js" charset="utf-8"></script>

<!-- d3-tip -->
<script type="text/javascript" src=https://cdnjs.cloudflare.com/ajax/libs/d3-tip/0.9.1/d3-tip.min.js></script>

<!-- d3-flamegraph -->
<script type="text/javascript" src="https://cdn.jsdelivr.net/gh/spiermar/[email protected]/dist/d3-flamegraph.min.js"></script>

<script type="text/javascript">
var flameGraph = d3.flamegraph()
  .width(960)
  .cellHeight(18)
  .transitionDuration(750)
  .minFrameSize(5)
  .transitionEase(d3.easeCubic)
  .sort(true)
  //Example to sort in reverse order
  //.sort(function(a,b){ return d3.descending(a.name, b.name);})
  .title("")
  .onClick(onClick)
  .differential(false)
  .selfValue(false);


// Example on how to use custom tooltips using d3-tip.
// var tip = d3.tip()
//   .direction("s")
//   .offset([8, 0])
//   .attr('class', 'd3-flame-graph-tip')
//   .html(function(d) { return "name: " + d.data.name + ", value: " + d.data.value; });

// flameGraph.tooltip(tip);

var details = document.getElementById("details");
flameGraph.setDetailsElement(details);

// Example on how to use custom labels
// var label = function(d) {
//  return "name: " + d.name + ", value: " + d.value;
// }
// flameGraph.label(label);

// Example of how to set fixed chart height
// flameGraph.height(540);

d3.select("#chart")
    .datum(#{ json })
    .call(flameGraph);

document.getElementById("form").addEventListener("submit", function(event){
  event.preventDefault();
  search();
});

function search() {
  var term = document.getElementById("term").value;
  flameGraph.search(term);
}

function clear() {
  document.getElementById('term').value = '';
  flameGraph.clear();
}

function resetZoom() {
  flameGraph.resetZoom();
}

function onClick(d) {
  console.info("Clicked on " + d.data.name);
}
</script>
  </body>
</html>
  END
end

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# File 'lib/stackprof/report.rb', line 65

def print_debug
  pp @data
end

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# File 'lib/stackprof/report.rb', line 69

def print_dump(f=STDOUT)
  f.puts Marshal.dump(@data.reject{|k,v| k == :files })
end

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# File 'lib/stackprof/report.rb', line 607

def print_file(filter, f = STDOUT)
  filter = /#{Regexp.escape filter}/ unless Regexp === filter
  list = files.select{ |name, lines| name =~ filter }
  list.sort_by{ |file, vals| -vals.values.inject(0){ |sum, n| sum + (n.is_a?(Array) ? n[1] : n) } }.each do |file, lines|
    source_display(f, file, lines)
  end
end

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# File 'lib/stackprof/report.rb', line 597

def print_files(sort_by_total=false, limit=nil, f = STDOUT)
  list = files.map{ |file, vals| [file, vals.values.inject([0,0]){ |sum, n| add_lines(sum, n) }] }
  list = list.sort_by{ |file, samples| -samples[1] }
  list = list.first(limit) if limit
  list.each do |file, vals|
    total_samples, samples = *vals
    f.printf "% 5d  (%5.1f%%) / % 5d  (%5.1f%%)   %s\n", total_samples, (100.0*total_samples/overall_samples), samples, (100.0*samples/overall_samples), file
  end
end

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# File 'lib/stackprof/report.rb', line 124

def print_flamegraph(f, skip_common, alphabetical=false)
  raise "profile does not include raw samples (add `raw: true` to collecting StackProf.run)" unless raw = data[:raw]

  stacks = []
  max_x = 0
  max_y = 0

  idx = 0
  loop do
    len = raw[idx]
    break unless len
    max_y = len if len > max_y

    stack = StackCursor.new(raw, idx, len)
    stacks << stack
    max_x += stack.weight

    idx += len + 2
  end

  stacks.sort! if alphabetical

  f.puts 'flamegraph(['
  max_y.times do |y|
    row_prev = nil
    row_width = 0
    x = 0

    stacks.each do |stack|
      weight = stack.weight
      cell = stack[y] unless y == stack.length-1

      if cell.nil?
        if row_prev
          flamegraph_row(f, x - row_width, y, row_width, row_prev)
        end

        row_prev = nil
        x += weight
        next
      end

      if row_prev.nil?        # start new row with this cell
        row_width = weight
        row_prev = cell
        x += weight

      elsif row_prev == cell  # grow current row along x-axis
        row_width += weight
        x += weight

      else                    # end current row and start new row
        flamegraph_row(f, x - row_width, y, row_width, row_prev)
        x += weight
        row_prev = cell
        row_width = weight
      end

      row_prev = cell
    end

    if row_prev
      next if skip_common && row_width == max_x

      flamegraph_row(f, x - row_width, y, row_width, row_prev)
    end
  end
  f.puts '])'
end

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# File 'lib/stackprof/report.rb', line 411

def print_graphviz(options = {}, f = STDOUT)
  if filter = options[:filter]
    mark_stack = []
    list = frames(true)
    list.each{ |addr, frame| mark_stack << addr if frame[:name] =~ filter }
    while addr = mark_stack.pop
      frame = list[addr]
      unless frame[:marked]
        mark_stack += frame[:edges].map{ |addr, weight| addr if list[addr][:total_samples] <= weight*1.2 }.compact if frame[:edges]
        frame[:marked] = true
      end
    end
    list = list.select{ |addr, frame| frame[:marked] }
    list.each{ |addr, frame| frame[:edges] && frame[:edges].delete_if{ |k,v| list[k].nil? } }
    list
  else
    list = frames(true)
  end


  limit = options[:limit]
  fraction = options[:node_fraction]

  included_nodes = {}
  node_minimum = fraction ? (fraction * overall_samples).ceil : 0

  f.puts "digraph profile {"
  f.puts "Legend [shape=box,fontsize=24,shape=plaintext,label=\""
  f.print "Total samples: #{overall_samples}\\l"
  f.print "Showing top #{limit} nodes\\l" if limit
  f.print "Dropped nodes with < #{node_minimum} samples\\l" if fraction
  f.puts "\"];"

  list.each_with_index do |(frame, info), index|
    call, total = info.values_at(:samples, :total_samples)
    break if total < node_minimum || (limit && index >= limit)

    sample = ''.dup
    sample << "#{call} (%2.1f%%)\\rof " % (call*100.0/overall_samples) if call < total
    sample << "#{total} (%2.1f%%)\\r" % (total*100.0/overall_samples)
    fontsize = (1.0 * call / max_samples) * 28 + 10
    size = (1.0 * total / overall_samples) * 2.0 + 0.5

    f.puts "  \"#{frame}\" [size=#{size}] [fontsize=#{fontsize}] [penwidth=\"#{size}\"] [shape=box] [label=\"#{info[:name]}\\n#{sample}\"];"
    included_nodes[frame] = true
  end

  list.each do |frame, info|
    next unless included_nodes[frame]

    if edges = info[:edges]
      edges.each do |edge, weight|
        next unless included_nodes[edge]

        size = (1.0 * weight / overall_samples) * 2.0 + 0.5
        f.puts "  \"#{frame}\" -> \"#{edge}\" [label=\"#{weight}\"] [weight=\"#{weight}\"] [penwidth=\"#{size}\"];"
      end
    end
  end
  f.puts "}"
end

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# File 'lib/stackprof/report.rb', line 73

def print_json(f=STDOUT)
  require "json"
  f.puts JSON.generate(@data, max_nesting: false)
end

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# File 'lib/stackprof/report.rb', line 523

def print_method(name, f = STDOUT)
  name = /#{name}/ unless Regexp === name
  frames.each do |frame, info|
    next unless info[:name] =~ name
    file, line = info.values_at(:file, :line)
    line ||= 1

    lines = info[:lines]
    maxline = lines ? lines.keys.max : line + 5
    f.printf "%s (%s:%d)\n", info[:name], file, line
    f.printf "  samples: % 5d self (%2.1f%%)  /  % 5d total (%2.1f%%)\n", info[:samples], 100.0*info[:samples]/overall_samples, info[:total_samples], 100.0*info[:total_samples]/overall_samples

    if (callers = callers_for(frame)).any?
      f.puts "  callers:"
      callers = callers.sort_by(&:last).reverse
      callers.each do |name, weight|
        f.printf "   % 5d  (% 8s)  %s\n", weight, "%3.1f%%" % (100.0*weight/info[:total_samples]), name
      end
    end

    if callees = info[:edges]
      f.printf "  callees (%d total):\n", info[:total_samples]-info[:samples]
      callees = callees.map{ |k, weight| [data[:frames][k][:name], weight] }.sort_by{ |k,v| -v }
      callees.each do |name, weight|
        f.printf "   % 5d  (% 8s)  %s\n", weight, "%3.1f%%" % (100.0*weight/(info[:total_samples]-info[:samples])), name
      end
    end

    f.puts "  code:"
    source_display(f, file, lines, line-1..maxline)
  end
end

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# File 'lib/stackprof/report.rb', line 78

def print_stackcollapse
  raise "profile does not include raw samples (add `raw: true` to collecting StackProf.run)" unless raw = data[:raw]

  while len = raw.shift
    frames = raw.slice!(0, len)
    weight = raw.shift

    print frames.map{ |a| data[:frames][a][:name] }.join(';')
    puts " #{weight}"
  end
end

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# File 'lib/stackprof/report.rb', line 473

def print_text(sort_by_total=false, limit=nil, select_files= nil, reject_files=nil, select_names=nil, reject_names=nil, f = STDOUT)
  f.puts "=================================="
  f.printf "  Mode: #{modeline}\n"
  f.printf "  Samples: #{@data[:samples]} (%.2f%% miss rate)\n", 100.0*@data[:missed_samples]/(@data[:missed_samples]+@data[:samples])
  f.printf "  GC: #{@data[:gc_samples]} (%.2f%%)\n", 100.0*@data[:gc_samples]/@data[:samples]
  f.puts "=================================="
  f.printf "% 10s    (pct)  % 10s    (pct)     FRAME\n" % ["TOTAL", "SAMPLES"]
  list = frames(sort_by_total)
  list.select!{|_, info| select_files.any?{|path| info[:file].start_with?(path)}} if select_files
  list.select!{|_, info| select_names.any?{|reg| info[:name] =~ reg}} if select_names
  list.reject!{|_, info| reject_files.any?{|path| info[:file].start_with?(path)}} if reject_files
  list.reject!{|_, info| reject_names.any?{|reg| info[:name] =~ reg}} if reject_names
  list = list.first(limit) if limit
  list.each do |frame, info|
    call, total = info.values_at(:samples, :total_samples)
    f.printf "% 10d % 8s  % 10d % 8s     %s\n", total, "(%2.1f%%)" % (total*100.0/overall_samples), call, "(%2.1f%%)" % (call*100.0/overall_samples), info[:name]
  end
end

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# File 'lib/stackprof/report.rb', line 90

def print_timeline_flamegraph(f=STDOUT, skip_common=true)
  print_flamegraph(f, skip_common, false)
end

#versionObject


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# File 'lib/stackprof/report.rb', line 30

def version
  @data[:version]
end

#walk_method(name) ⇒ Object

Walk up and down the stack from a given starting point (name). Loops until `:exit` is selected


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# File 'lib/stackprof/report.rb', line 558

def walk_method(name)
  method_choice  = /#{Regexp.escape name}/
  invalid_choice = false

  # Continue walking up and down the stack until the users selects "exit"
  while method_choice != :exit
    print_method method_choice unless invalid_choice
    STDOUT.puts "\n\n"

    # Determine callers and callees for the current frame
    new_frames  = frames.select  {|_, info| info[:name] =~ method_choice }
    new_choices = new_frames.map {|frame, info| [
      callers_for(frame).sort_by(&:last).reverse.map(&:first),
      (info[:edges] || []).map{ |k, w| [data[:frames][k][:name], w] }.sort_by{ |k,v| -v }.map(&:first)
    ]}.flatten + [:exit]

    # Print callers and callees for selection
    STDOUT.puts "Select next method:"
    new_choices.each_with_index do |method, index|
      STDOUT.printf "%2d)  %s\n", index + 1, method.to_s
    end

    # Pick selection
    STDOUT.printf "> "
    selection = STDIN.gets.chomp.to_i - 1
    STDOUT.puts "\n\n\n"

    # Determine if it was a valid choice
    # (if not, don't re-run .print_method)
    if new_choice = new_choices[selection]
      invalid_choice = false
      method_choice = new_choice == :exit ? :exit : %r/^#{Regexp.escape new_choice}$/
    else
      invalid_choice = true
      STDOUT.puts "Invalid choice.  Please select again..."
    end
  end
end