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# Copyright 2018 Marketplacer under the MIT license.
class CapybaraTimers
class << self
attr_accessor :nesting, :total_time
def setup
# Wrap every DSL method and every matcher with our timing function
Capybara::Session::DSL_METHODS.each do |name|
setup_timer_on_method(Capybara::DSL, name)
end
Capybara::Node::Matchers.public_instance_methods.each do |name|
setup_timer_on_method(Capybara::Node::Base, name)
end
# The .path method can be quite slow in selenium - up to 500ms
setup_timer_on_method(Capybara::Selenium::Node, :path)
RSpec.configure do |config|
config.before :suite do
CapybaraTimers.total_time = 0
end
config.after :suite do
$stderr.printf "CAPYBARA TOTAL %0.2fs\n", CapybaraTimers.total_time if CapybaraTimers.total_time > 0
end
config.before :each do
CapybaraTimers.nesting = 0
end
end
end
private
def setup_timer_on_method klass, name
klass.send(:alias_method, "__timing_#{name}", name)
klass.send(:define_method, name) do |*args, &block|
result = nil
CapybaraTimers.nesting += 1
elapsed = Benchmark.realtime do
result = send("__timing_#{name}", *args, &block)
end
# Don't add to our global timer if we're nested as we don't
# want to double-count
CapybaraTimers.total_time += elapsed if CapybaraTimers.nesting == 1
# Find the first thing in the backtrace that matches our own repo
callers = caller_locations(1)
my_caller = callers.find do |c|
c.path && c.path.include?(Rails.root.to_s) && !c.path.include?("capybara_timers")
end
my_caller ||= callers.first # Unlikely, but possible.
path = my_caller.path.gsub(Rails.root.to_s + '/', "")
nesting = " " * ((CapybaraTimers.nesting - 1) * 2)
# Only inspect the first arg, and only inspect if a string or int - if we get
# passed a Node calling inspect on it triggers .path, which is slow.
args_s = args.first.is_a?(String) || args.first.is_a?(Integer) ? args.first.inspect : args.class.to_s
if elapsed >= 0.01
$stderr.printf "%s%0.2fs %s:%d %s %s\n", nesting, elapsed, path, my_caller.lineno, name, args_s
end
CapybaraTimers.nesting -= 1
# Ensure we return the original result to the caller
result
end
end
end
end
CapybaraTimers.setup if ENV["CAPYBARA_TIMERS"]
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