class Sentry::LineCache

line should be the line requested by lineno. See specs for more information.
file. The number of lines retrieved is (2 * context) + 1, the middle
Returns an Array of Strings representing the lines in the source
Any linecache you provide to Sentry must implement this method.

def get_file_context(filename, lineno, context)
  return nil, nil, nil unless valid_path?(filename)
  lines = Array.new(2 * context + 1) do |i|
    getline(filename, lineno - context + i)
  end
  [lines[0..(context - 1)], lines[context], lines[(context + 1)..-1]]
end