class ActiveSupport::BacktraceCleaner

Inspired by the Quiet Backtrace gem by thoughtbot.
These two methods will give you a completely untouched backtrace.
of the backtrace, you can call BacktraceCleaner#remove_filters!
BacktraceCleaner so that it does not filter or modify the paths of any lines
backtrace to a pristine state. If you need to reconfigure an existing
BacktraceCleaner#remove_silencers!, which will restore the
and show as much data as possible, you can always call
To reconfigure an existing BacktraceCleaner (like the default one in Rails)
bc.clean(exception.backtrace) # perform the cleanup
bc.add_silencer { |line| /puma|rubygems/.match?(line) } # skip any lines from puma or rubygems
bc.add_filter { |line| line.gsub(Rails.root.to_s, ”) } # strip the Rails.root prefix
bc = ActiveSupport::BacktraceCleaner.new
can focus on the rest.
is to exclude the output of a noisy library from the backtrace, so that you
app directory instead of the file system root. The typical silencer use case
information from the start of each line, and view file paths relevant to the
lines entirely. The typical filter use case is to remove lengthy path
Filters are used to modify lines of data, while silencers are used to remove
lines remain.
silencers are used to remove the noisy lines, so that only the most relevant
noise, and adds debugging time. With a BacktraceCleaner, filters and
under review. This makes it hard to find the signal amongst the backtrace
Backtraces often include many lines that are not relevant for the context
= Backtrace Cleaner

def add_filter(&block)

backtrace_cleaner.add_filter { |line| line.gsub(Rails.root.to_s, '') }
# Will turn "/my/rails/root/app/models/person.rb" into "/app/models/person.rb"

mapped against this filter.
Adds a filter from the block provided. Each line in the backtrace will be

def add_filter(&block)
  @filters << block
end

def add_gem_filter

def add_gem_filter
  gems_paths = (Gem.path | [Gem.default_dir]).map { |p| Regexp.escape(p) }
  return if gems_paths.empty?
  gems_regexp = %r{\A(#{gems_paths.join('|')})/(bundler/)?gems/([^/]+)-([\w.]+)/(.*)}
  gems_result = '\3 (\4) \5'
  add_filter { |line| line.sub(gems_regexp, gems_result) }
end

def add_gem_silencer

def add_gem_silencer
  add_silencer { |line| FORMATTED_GEMS_PATTERN.match?(line) }
end

def add_silencer(&block)

backtrace_cleaner.add_silencer { |line| /puma/.match?(line) }
# Will reject all lines that include the word "puma", like "/gems/puma/server.rb" or "/app/my_puma_server/rb"

for a given line, it will be excluded from the clean backtrace.
Adds a silencer from the block provided. If the silencer returns +true+

def add_silencer(&block)
  @silencers << block
end

def add_stdlib_silencer

def add_stdlib_silencer
  add_silencer { |line| line.start_with?(RbConfig::CONFIG["rubylibdir"]) }
end

def clean(backtrace, kind = :silent)

against it. Filters run first, then silencers.
Returns the backtrace after all filters and silencers have been run

def clean(backtrace, kind = :silent)
  filtered = filter_backtrace(backtrace)
  case kind
  when :silent
    silence(filtered)
  when :noise
    noise(filtered)
  else
    filtered
  end
end

def clean_frame(frame, kind = :silent)

returns +nil+ if the frame was silenced.
Returns the frame with all filters applied.

def clean_frame(frame, kind = :silent)
  frame = frame.to_s
  @filters.each do |f|
    frame = f.call(frame.to_s)
  end
  case kind
  when :silent
    frame unless @silencers.any? { |s| s.call(frame) }
  when :noise
    frame if @silencers.any? { |s| s.call(frame) }
  else
    frame
  end
end

def filter_backtrace(backtrace)

def filter_backtrace(backtrace)
  @filters.each do |f|
    backtrace = backtrace.map { |line| f.call(line.to_s) }
  end
  backtrace
end

def initialize

def initialize
  @filters, @silencers = [], []
  add_gem_filter
  add_gem_silencer
  add_stdlib_silencer
end

def noise(backtrace)

def noise(backtrace)
  backtrace.select do |line|
    @silencers.any? do |s|
      s.call(line.to_s)
    end
  end
end

def remove_filters!

filtered out.
need to see entire filepaths in the backtrace that you had already
Removes all filters, but leaves in the silencers. Useful if you suddenly

def remove_filters!
  @filters = []
end

def remove_silencers!

the libraries you use.
context of debugging suddenly expands as you suspect a bug in one of
Removes all silencers, but leaves in the filters. Useful if your

def remove_silencers!
  @silencers = []
end

def silence(backtrace)

def silence(backtrace)
  @silencers.each do |s|
    backtrace = backtrace.reject { |line| s.call(line.to_s) }
  end
  backtrace
end

Modules

Classes